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Commercial and US Government Launch Vehicles => Blue Origin => Topic started by: Steven Pietrobon on 02/25/2016 10:14 PM

Title: Blue Origin's BE-4 Engine
Post by: Steven Pietrobon on 02/25/2016 10:14 PM
I think its time this engine has its own thread. Here are some images from

https://www.blueorigin.com/be4
Title: Re: Blue Origin's BE-4 Engine
Post by: Steven Pietrobon on 02/25/2016 10:17 PM
Here is the fact sheet. Not much technical information, but sea level thrust is 2.45 MN (550 klbf). Propellants are liquid oxygen and liquid methane (liquified natural gas). Cycle is oxygen rich staged combustion.
Title: Re: Blue Origin's BE-4 Engine
Post by: Steven Pietrobon on 02/26/2016 12:22 AM
Images of the BE-4 configurations.
Title: Re: Blue Origin's BE-4 Engine
Post by: Apollo100 on 02/26/2016 03:32 PM
The relative sizes of the hardware in the pictures is a bit off from the 3D models. Looks like the main turbopump shown on the floor and in the test stand is the smaller 400K version. Not sure why they would test it in the horizontal orientation if it is vertical in the engine.
Title: Re: Blue Origin's BE-4 Engine
Post by: ethan829 on 02/26/2016 04:33 PM
Tory Bruno just said on reddit that two BE-4s will cost less than a single RD-180. Obviously that's a ballpark estimate and could very well change, but it's nice to know the target prices are competitive.

https://www.reddit.com/r/ula/comments/47jsfy/new_be4_information_page_from_blue_origin/d0erahf (https://www.reddit.com/r/ula/comments/47jsfy/new_be4_information_page_from_blue_origin/d0erahf)
Quote
However, as a pair, BE4 or AR1 will offer around 30% more thrust than a single RD180. The pair will cost less than a single RD180 and with increased tank size, there will be fewer SRMs for the same mission.
Title: Re: Blue Origin's BE-4 Engine
Post by: Prober on 02/26/2016 04:45 PM
Tory Bruno just said on reddit that two BE-4s will cost less than a single RD-180. Obviously that's a ballpark estimate and could very well change, but it's nice to know the target prices are competitive.

https://www.reddit.com/r/ula/comments/47jsfy/new_be4_information_page_from_blue_origin/d0erahf (https://www.reddit.com/r/ula/comments/47jsfy/new_be4_information_page_from_blue_origin/d0erahf)
Quote
However, as a pair, BE4 or AR1 will offer around 30% more thrust than a single RD180. The pair will cost less than a single RD180 and with increased tank size, there will be fewer SRMs for the same mission.


strange he has listed the AR1 in that comment.   The final papers must not be signed and the AR1 is the backup?

Title: Re: Blue Origin's BE-4 Engine
Post by: kch on 02/26/2016 04:58 PM
Tory Bruno just said on reddit that two BE-4s will cost less than a single RD-180. Obviously that's a ballpark estimate and could very well change, but it's nice to know the target prices are competitive.

https://www.reddit.com/r/ula/comments/47jsfy/new_be4_information_page_from_blue_origin/d0erahf (https://www.reddit.com/r/ula/comments/47jsfy/new_be4_information_page_from_blue_origin/d0erahf)
Quote
However, as a pair, BE4 or AR1 will offer around 30% more thrust than a single RD180. The pair will cost less than a single RD180 and with increased tank size, there will be fewer SRMs for the same mission.


strange he has listed the AR1 in that comment.   The final papers must not be signed and the AR1 is the backup?

Right!  :)

From the Blue Origin Update and Discussion Thread:


Tory Bruno has mentioned on reddit that Blue Origin agreed to ULA's target cost for BE-4, although no mention of any specific number.

https://www.reddit.com/r/ula/comments/43v33x/be4_forgings_assemble_full_engine_testing_later/czq86eb (https://www.reddit.com/r/ula/comments/43v33x/be4_forgings_assemble_full_engine_testing_later/czq86eb)
Quote
BE4 is our primary path because it started first, is fully funded, and Blue has signed up to our target cost. AR1 is our back up because engines are complicated, risky, and BE4 will be the largest methane engine ever built (so there's technical risk). I plan to downselect after BE4's full scale static testing in about a year. That's when we'll know if the technology will work and can be on schedule.
Title: Re: Blue Origin's BE-4 Engine
Post by: Damon Hill on 03/02/2016 03:17 AM
Where is the engine being built, and tested?  I doubt it's the Kent, WA facility because of the noise, though Kent has equipment in the back of the main building that suspiciously suggests an engine test facility.

--Damon
Title: Re: Blue Origin's BE-4 Engine
Post by: jongoff on 03/02/2016 03:34 AM
Where is the engine being built, and tested?  I doubt it's the Kent, WA facility because of the noise, though Kent has equipment in the back of the main building that suspiciously suggests an engine test facility.

--Damon

The engine is probably being built in Kent, but the stand for BE-4 is in West Texas. There was a picture of the stand in one of these threads.

~Jon
Title: Re: Blue Origin's BE-4 Engine
Post by: GreenShrike on 03/09/2016 04:41 PM
Ars Technica reports that the combustion chamber pressure of the BE-4 is 1950 psi.

Quote
Bezos explained his philosophy on how to build a successful reusable engine: “Our strategy is we like to choose a medium-performing version of a high-performance architecture.” Here’s what that means: The Russian RD-180 engine is a high-performing version of a high performance architecture. It uses the best materials and pushes the performance envelope. It is the Ferrari of engines. But that comes with a cost. When it fires, the RD-180 engines produces extremely high chamber pressures of up to 3,700 psi. By comparison, the BE-4 engine produces a chamber pressure of 1,950 psi.

http://arstechnica.com/science/2016/03/behind-the-curtain-ars-goes-inside-blue-origins-secretive-rocket-factory/ (http://arstechnica.com/science/2016/03/behind-the-curtain-ars-goes-inside-blue-origins-secretive-rocket-factory/)
Title: Re: Blue Origin's BE-4 Engine
Post by: baldusi on 03/09/2016 05:39 PM
Ars Technica reports that the combustion chamber pressure of the BE-4 is 1950 psi.

Quote
Bezos explained his philosophy on how to build a successful reusable engine: “Our strategy is we like to choose a medium-performing version of a high-performance architecture.” Here’s what that means: The Russian RD-180 engine is a high-performing version of a high performance architecture. It uses the best materials and pushes the performance envelope. It is the Ferrari of engines. But that comes with a cost. When it fires, the RD-180 engines produces extremely high chamber pressures of up to 3,700 psi. By comparison, the BE-4 engine produces a chamber pressure of 1,950 psi.

http://arstechnica.com/science/2016/03/behind-the-curtain-ars-goes-inside-blue-origins-secretive-rocket-factory/ (http://arstechnica.com/science/2016/03/behind-the-curtain-ars-goes-inside-blue-origins-secretive-rocket-factory/)
Yes, and the RD-180 is still rated for 10 missions. No wonder it is not even close to the RD-180 in performance.
Title: Re: Blue Origin's BE-4 Engine
Post by: Ronsmytheiii on 03/12/2016 12:43 PM
Quote
CULBERSON COUNTY, Texas (Blue Origin PR) — BE-4 testing is well underway at Blue Origin. To date, we’ve completed more than 170 staged-combustion tests – including 51 starts on a single regeneratively cooled chamber and nozzle. The preburner performed flawlessly and the main injector consistently demonstrated performance at the high end of our predictions, giving us confidence that we’ll get good specific impulse when we go to full-scale engine testing later this year.

Also includes news on more test stand construction:

Quote
One of the many benefits of a privately funded engine development is that we can make and implement decisions quickly. Building these two new test cells is a $10 million commitment, and we as a team made the decision to move forward in 10 minutes.

http://www.parabolicarc.com/2016/03/11/be4-engine-testing-update-jeff-bezos/
Title: Re: Blue Origin's BE-4 Engine
Post by: J-V on 03/12/2016 07:24 PM
FYI The article in Parabolicarc is essentially an email from the BO mailing list, sent few days ago. You can subscribe in https://www.blueorigin.com I subscribed several weeks ago and this was the first mail from Jeff so far. Sorry for not sending it here, but mobile...
Title: Re: Blue Origin's BE-4 Engine
Post by: sanman on 03/14/2016 01:30 AM
Old press conference from Sept-2014

https://www.youtube.com/watch?v=M89o79gqWec

PS: that first pic Steve posted has such a beautiful blue flame - I'll bet it makes night launches look spectacular
Title: Re: Blue Origin's BE-4 Engine
Post by: Nilof on 03/17/2016 12:59 PM
...so now that we have the chamber pressure information available, we could start speculating about other numbers. Plugging it into MPA, assuming an Isp-optimized O/F ratio and assuming that the nozzle is optimized for maximum thrust at sea level (more likely it'll be optimized for a somewhat lower pressure since Vulcan stages late) , I get a theoretical ideal specific impulse of 327 s SL and 351 s vac.

MPA lite gives me a likely "as it turns out" specific impulse of 315 s SL and 339 s vac. This is where having the full version of the program would be nice to better approximate staged combustion efficiency and get an approximate T/W ratio. But either way, it seems to predict a somewhat lower specific impulse with the BE-4 than with the RD-180, and with a less dense fuel composition. Then again, SpaceX's Raptor development seems to suggest that Methane performs above their initial expectations, so it may be the case that the BE-4 performance will also be closer to its theoretical ideal.

Here's the full output from MPA: # Engine name: BE-4
# Thu 17. Mar 14:46:58 2016
#
#***************************************************************************************************
# Propellant Specification
#---------------------------------------------------------------------------------------------------
#    Component  Temp.          Mass          Mole
#                 [K]      fraction      fraction
#---------------------------------------------------------------------------------------------------
#       CH4(L)  111.6     0.2286613     0.3715842
#        O2(L)   90.2     0.7713387     0.6284158
#---------------------------------------------------------------------------------------------------
#              Total:     1.0000000     1.0000000
#---------------------------------------------------------------------------------------------------
#    Exploded formula:   (O)1.257 (C)0.372 (H)1.486
#                O/F:     3.3732812
#              O/F 0:     3.9892635 (stoichiometric)
#              alpha:     0.8455900 (oxidizer excess coefficient)
#---------------------------------------------------------------------------------------------------
#
# Table 1. Thermodynamic properties
#---------------------------------------------------------------------------------------------------
#          Parameter      Injector    Nozzle inl    Nozzle thr    Nozzle exi          Unit   
#---------------------------------------------------------------------------------------------------
            Pressure       13.4000       13.4000        7.7479        0.1013           MPa   
         Temperature     3633.4053     3633.4053     3449.6604     2120.8213             K   
            Enthalpy    -1584.7448    -1584.7448    -2320.7245    -6733.3422         kJ/kg   
             Entropy       11.9543       11.9543       11.9543       11.9543     kJ/(kg·K)   
Specific heat (p=const)        6.4073        6.4073        6.2065        2.3677     kJ/(kg·K)   
Specific heat (V=const)        5.4605        5.4605        5.3268        2.0007     kJ/(kg·K)   
        Gas constant        0.3818        0.3818        0.3771        0.3559     kJ/(kg·K)   
    Molecular weight       21.7772       21.7772       22.0482       23.3617                 
 Isentropic exponent        1.1344        1.1344        1.1315        1.1828                 
             Density        9.6596        9.6596        5.9559        0.1342         kg/m³   
      Sonic velocity     1254.4618     1254.4618     1213.2454      944.8885           m/s   
            Velocity        0.0000        0.0000     1213.2454     3208.9242           m/s   
         Mach number        0.0000        0.0000        1.0000        3.3961                 
          Area ratio        0.0000        0.0000        1.0000       16.7747                 
           Mass flux        0.0000        0.0000     7225.9842      430.7661     kg/(m²·s)   
#---------------------------------------------------------------------------------------------------
#
#---------------------------------------------------------------------------------------------------
#
# Table 2. Fractions of the combustion products
#---------------------------------------------------------------------------------------------------
#            Species      Injector      Injector    Nozzle inl    Nozzle inl    Nozzle thr    Nozzle thr    Nozzle exi    Nozzle exi   
#                       mass fract    mole fract    mass fract    mole fract    mass fract    mole fract    mass fract    mole fract   
#---------------------------------------------------------------------------------------------------
                  CO     0.2310086     0.1796041     0.2310086     0.1796041     0.2202208     0.1733472     0.1561277     0.1302175   
                 CO2     0.2642280     0.1307480     0.2642280     0.1307480     0.2812219     0.1408886     0.3819814     0.2027683   
                COOH     0.0000486     0.0000235     0.0000486     0.0000235     0.0000281     0.0000138     0.0000000     0.0000000   
                   H     0.0008998     0.0194399     0.0008998     0.0194399     0.0007611     0.0166498     0.0000418     0.0009684   
                  H2     0.0074850     0.0808590     0.0074850     0.0808590     0.0070773     0.0774057     0.0065192     0.0755498   
                 H2O     0.4123624     0.4984720     0.4123624     0.4984720     0.4216903     0.5160903     0.4545258     0.5894158   
                H2O2     0.0000482     0.0000308     0.0000482     0.0000308     0.0000280     0.0000181     0.0000000     0.0000000   
     HCHO,formaldehy     0.0000011     0.0000008     0.0000011     0.0000008     0.0000006     0.0000004     0.0000000     0.0000000   
                 HCO     0.0000277     0.0000208     0.0000277     0.0000208     0.0000150     0.0000114     0.0000000     0.0000000   
               HCOOH     0.0000099     0.0000047     0.0000099     0.0000047     0.0000056     0.0000027     0.0000000     0.0000000   
                 HO2     0.0002153     0.0001421     0.0002153     0.0001421     0.0001292     0.0000863     0.0000000     0.0000000   
                   O     0.0060003     0.0081672     0.0060003     0.0081672     0.0045170     0.0062247     0.0000058     0.0000084   
                  O2     0.0282713     0.0192404     0.0282713     0.0192404     0.0232214     0.0160003     0.0000382     0.0000279   
                  O3     0.0000003     0.0000001     0.0000003     0.0000001     0.0000000     0.0000000     0.0000000     0.0000000   
                  OH     0.0493935     0.0632464     0.0493935     0.0632464     0.0410836     0.0532605     0.0007599     0.0010438   
#---------------------------------------------------------------------------------------------------
#
#---------------------------------------------------------------------------------------------------
#
# Table 3. Theoretical (ideal) performance
#---------------------------------------------------------------------------------------------------
#          Parameter     Sea level    Optimum ex        Vacuum          Unit   
#---------------------------------------------------------------------------------------------------
Characteristic velocity        0.0000     1854.4200        0.0000           m/s   
Effective exhaust velocity     3208.9200     3208.9200     3444.1400           m/s   
Specific impulse (by mass)     3208.9200     3208.9200     3444.1400        N·s/kg   
Specific impulse (by weight)      327.2200      327.2200      351.2100             s   
  Thrust coefficient        1.7304        1.7304        1.8573                 
#---------------------------------------------------------------------------------------------------
#
#---------------------------------------------------------------------------------------------------
#
# Table 4. Estimated delivered performance
#---------------------------------------------------------------------------------------------------
#          Parameter     Sea level    Optimum ex        Vacuum          Unit   
#---------------------------------------------------------------------------------------------------
Characteristic velocity        0.0000     1834.4100        0.0000           m/s   
Effective exhaust velocity     3092.1300     3092.1300     3327.3500           m/s   
Specific impulse (by mass)     3092.1300     3092.1300     3327.3500        N·s/kg   
Specific impulse (by weight)      315.3100      315.3100      339.3000             s   
  Thrust coefficient        1.6856        1.6856        1.8139                 
#---------------------------------------------------------------------------------------------------
#
#Ambient condition for optimum expansion:  H=0.00 km, p=1.000 atm
#
#
Title: Re: Blue Origin's BE-4 Engine
Post by: GreenShrike on 03/17/2016 04:18 PM
Yes, and the RD-180 is still rated for 10 missions. No wonder it is not even close to the RD-180 in performance.

...so now that we have the chamber pressure information available, we could start speculating about other numbers. Plugging it into MPA, assuming an Isp-optimized O/F ratio and assuming that the nozzle is optimized for maximum thrust at sea level (more likely it'll be optimized for a somewhat lower pressure since Vulcan stages late) , I get a theoretical ideal specific impulse of 327 s SL and 351 s vac.

MPA lite gives me a likely "as it turns out" specific impulse of 315 s SL and 339 s vac. This is where having the full version of the program would be nice to better approximate staged combustion efficiency and get an approximate T/W ratio. But either way, it seems to predict a somewhat lower specific impulse with the BE-4 than with the RD-180, and with a less dense fuel composition.

The ISP of the RD-180 is around 312s/338s, according to SpaceLaunchReport, which is pretty much what you calculate for the BE-4. From baldusi's comments -- and what I understand about chamber pressure versus ISP -- I was expecting the BE-4 to be clearly under the RD-180's numbers.

Is the BE-4's supposed lower performance due to the lower density of methane versus RP-1?
Title: Re: Blue Origin's BE-4 Engine
Post by: baldusi on 03/17/2016 06:46 PM
Methane usually has a 10s to 15s isp advantage wrt RP-1 with everything else being equal. RD-180 not only has amazing isp, it also has 79:1 T/W. Since propulsion is usually 35% to 50% of a first stage dry mass, that also counts a lot. Then you have the lower density of CH4. So anything using the BE-4 won't be as efficient as the RD-180. Oversizing overcomes the inefficiencies.
Title: Re: Blue Origin's BE-4 Engine
Post by: Nilof on 03/17/2016 07:41 PM
Main reason why predicted isp for BE-4 is lower than predicted isp for RD-180 is the lower chamber pressure. For a vacuum optimized engine methalox will always give that 10-15 sec Isp advantage since you can have any expansion ratio you want. At sea level the chamber pressure affects Isp much more more than propellant choice because it limits the expansion ratio you can have.
Title: Re: Blue Origin's BE-4 Engine
Post by: STS-200 on 03/18/2016 10:56 AM
I would be amazed if the engine they end up producing used such a low expansion ratio as 16.7.

For a booster engine, the criteria is usually closer to maximising efficiency over the flight while avoiding flow separation at sea level, rather than absolute maximum thrust. I would expect an ER of more like 25-35, depending on what they are optimising it for.

At ER=25, I would expect to see more like SL~310s, Vacuum~345s in a "real world" engine.
In absolute Isp numbers, I suspect they'll exceed the RD-180 on average. Whether they beat it in T/W or in other measure remains to be seen.

They appear to be trading the inherent efficiency of Methane as a fuel for a lower chamber pressure, which makes for a "less stressed" engine; probably easier to build and allowing for longer component or cycle life - they state they're building it to be re-usable.

Title: Re: Blue Origin's BE-4 Engine
Post by: TrevorMonty on 03/18/2016 11:31 AM
The BE4 should have high T/W as it uses additive manufacturing which helps to keep weight down.
Title: Re: Blue Origin's BE-4 Engine
Post by: Nilof on 03/18/2016 11:34 AM
At ER=25, I would expect to see more like SL~310s

With 1950 psi chamber pressure, I'd say that this is rather unlikely. More likely around 300s, especially if they go for an O/F ratio closer to 3.8 to improve density instead of optimizing only for Isp which was the basis for the 3.3 O/F ratio above.

On the Vulcan configuration which gets lift-off thrust from solids anyway, the BE-4 will probably have a somewhat longer nozzle and thus have a roughly similar and possibly slightly higher Isp than the RD-180 at altitude, but on the other hand have noticeably lower Isp at launch pad due to the lower chamber pressure. On Blue's own flyback booster where they need a short nozzle for landing and where liftoff thrust would be bottlenecked by the engine, they will probably go for a rather low expansion ratio and low Isp.

With that said, for a first stage total thrust to keep gravity losses down is much more important than a <5% Isp increase. The BE-4 only really needs a decent specific impulse. If it has a small enough physical footprint and is cheap enough that you can fit more engine thrust at the bottom of the rocket for a similar production cost, that configuration is going to be superior regardless of whether or not the specific impulse is slightly higher.
Title: Re: Blue Origin's BE-4 Engine
Post by: STS-200 on 03/18/2016 01:15 PM

With 1950 psi chamber pressure, I'd say that this is rather unlikely. More likely around 300s, especially if they go for an O/F ratio closer to 3.8 to improve density instead of optimizing only for Isp which was the basis for the 3.3 O/F ratio above.

If you change the O/F, you'll get different results.
Based on 3.3 and an output about midway between frozen-flow and shifting equilibrium simulations, with an optimised nozzle contour and decent combustion efficiency, you'll get about what I said.

On the Vulcan configuration which gets lift-off thrust from solids anyway, the BE-4 will probably have a somewhat longer nozzle and thus have a roughly similar and possibly slightly higher Isp than the RD-180 at altitude, but on the other hand have noticeably lower Isp at launch pad due to the lower chamber pressure. On Blue's own flyback booster where they need a short nozzle for landing and where liftoff thrust would be bottlenecked by the engine, they will probably go for a rather low expansion ratio and low Isp.

With that said, for a first stage total thrust to keep gravity losses down is much more important than a <5% Isp increase. The BE-4 only really needs a decent specific impulse. If it has a small enough physical footprint and is cheap enough that you can fit more engine thrust at the bottom of the rocket for a similar production cost, that configuration is going to be superior regardless of whether or not the specific impulse is slightly higher.

Building two different expansion ratios of the same engine isn't entirely trivial and it throws away some of the operational/production efficiencies of a single design.
In general terms, you are quite right about Isp/vehicle T/W, however there are still a lot of other trade-offs - Steering & G-Loads, Dynamic pressure, landing burn requirements and overall vehicle cost to name but a few.
Title: Re: Blue Origin's BE-4 Engine
Post by: Apollo100 on 03/18/2016 09:23 PM
The BE4 should have high T/W as it uses additive manufacturing which helps to keep weight down.

Huh?
Title: Re: Blue Origin's BE-4 Engine
Post by: Danderman on 03/19/2016 10:20 PM
About 20 years ago, Robert Zubrin was promoting methane engines (ultimately for use on Mars). When asked why methane was so great, if no was using it, his response was that "no one uses methane for rocket engines because no one uses methane for rocket engines".
Title: Re: Blue Origin's BE-4 Engine
Post by: R7 on 03/20/2016 06:24 PM
At ER=25, I would expect to see more like SL~310s

With 1950 psi chamber pressure, I'd say that this is rather unlikely.

No it isn't. If the illustrations are close to the truth the area ratio is somewhere in 23-25 region. 16.77 is way too low to match.

Your analysis has 1 atm nozzle exit pressure, that is too high. All real booster engines are overexpanded at sea level, many have the exit pressure at about 0.6 atm. This improves overall performance during flight.

I did some SWAG analysis (http://forum.nasaspaceflight.com/index.php?topic=35655.msg1262643#msg1262643) in 2014. Back then 130bar (1885 psi) Pc produced result close to the imagery and the few known facts. ~3% error, yay!
Title: Re: Blue Origin's BE-4 Engine
Post by: TrevorMonty on 03/20/2016 07:41 PM
Can anybody guess at throttle range of BE4. Blue plan to do vertical lands so deep throttling it one primary design features.
Title: Re: Blue Origin's BE-4 Engine
Post by: Steven Pietrobon on 03/21/2016 08:01 AM
Poster of BE-4 engine inside Atlas-V reception building. Taken from ULA OA-6 video.

http://youtube.com/watch?v=d2BvvTZlqLc
Title: Re: Blue Origin's BE-4 Engine
Post by: Nilof on 03/24/2016 10:07 AM
Can anybody guess at throttle range of BE4. Blue plan to do vertical lands so deep throttling it one primary design features.

Depends on expansion ratio. If it's in the ~16 range it should be able to get down to ~20% at sea level before hitting flow sep. At ER = 25 flow sep happens around ~30% throttle. If they use an altitude compensating nozzle they might be able to get lower.

At ER=25, I would expect to see more like SL~310s

With 1950 psi chamber pressure, I'd say that this is rather unlikely.

No it isn't. If the illustrations are close to the truth the area ratio is somewhere in 23-25 region. 16.77 is way too low to match.

Your analysis has 1 atm nozzle exit pressure, that is too high. All real booster engines are overexpanded at sea level, many have the exit pressure at about 0.6 atm. This improves overall performance during flight.

I did some SWAG analysis (http://forum.nasaspaceflight.com/index.php?topic=35655.msg1262643#msg1262643) in 2014. Back then 130bar (1885 psi) Pc produced result close to the imagery and the few known facts. ~3% error, yay!

The number that I disputed was the 310s+ specific impulse at ER = 25 which is rather optimistic, not the possibility of ER = 25.
Title: Re: Blue Origin's BE-4 Engine
Post by: Dante80 on 08/09/2016 05:39 AM
Regarding BE-4, here is what we know so far.

Propellants: LNG/LOX
Thrust: ~ 550,000 lbf
Chamber pressure: 1,950 psi
Cycle: ORSC (single shaft)
Isp:<311s SL, <338 vac. (for the booster variant in Vulcan)
TWR: <78
Re-usability: 25 complete missions, minimum.

The above design goals seem both tame and achievable. As we have seen with other engine designs (Merlin comes to mind) Blue should be able to uprate their engine a lot with the data they gain from flight experience.

Regarding Isp and TWR, the info we have on them comes from this:
http://arstechnica.com/science/2016/03/behind-the-curtain-ars-goes-inside-blue-origins-secretive-rocket-factory/2/ (http://arstechnica.com/science/2016/03/behind-the-curtain-ars-goes-inside-blue-origins-secretive-rocket-factory/2/)
Quote
Like the smaller BE-3 upon which it is modeled, a main feature of the BE-4 is its reusability, and it’s being designed to fly a minimum of 25 missions.

Bezos explained his philosophy on how to build a successful reusable engine: “Our strategy is we like to choose a medium-performing version of a high-performance architecture.” Here’s what that means: The Russian RD-180 engine is a high-performing version of a high performance architecture. It uses the best materials and pushes the performance envelope. It is the Ferrari of engines. But that comes with a cost. When it fires, the RD-180 engines produces extremely high chamber pressures of up to 3,700 psi. By comparison, the BE-4 engine produces a chamber pressure of 1,950 psi.

Developing an elite engine like the RD-180 was a decade-plus project, on par in complexity to the space shuttle’s main engines. It required expensive materials. On the plus side, this provides a lower weight engine and a higher thrust-to-weight ratio. But the engine’s specific impulse isn’t all that much greater than the BE-4, which can be built more easily, and because it doesn't push performance limits can be reused
Title: Re: Blue Origin's BE-4 Engine
Post by: guckyfan on 08/09/2016 07:50 AM
I saw the < sign. I now read the article. But I still cannot believe they are not aiming to be at least somewhat better than RD-180. Even with an initial value which can be improved upon later. After all they use methane instead of RP-1 which should allow for higher ISP, if not better T/W.
Title: Re: Blue Origin's BE-4 Engine
Post by: Hobbes-22 on 08/09/2016 09:09 AM
The BE4 should have high T/W as it uses additive manufacturing which helps to keep weight down.

Huh?

With AM, you can make large monolithic parts, where traditional manufacturing would need to split the part into manufacturable pieces, adding flanges and bolts to connect the parts. The printed part does not need those.
You might also be able to create (more efficient) part geometry that is impossible to do with traditional fabrication.
Title: Re: Blue Origin's BE-4 Engine
Post by: Dante80 on 08/09/2016 10:13 AM
I saw the < sign. I now read the article. But I still cannot believe they are not aiming to be at least somewhat better than RD-180. Even with an initial value which can be improved upon later. After all they use methane instead of RP-1 which should allow for higher ISP, if not better T/W.

Contrary to popular belief, it is not that easy to match RD-180 performance...with any hydrocarbon engine ( and especially if your goal is half the chamber pressure). Its not only the article though (which quotes Bezos, unless the reporter misrepresented him). The "Tobey comments" also seem to indicate the speculated performance goals above.

Quote
Comparing the two engine developments – Aerojet Rocketdyne pursuing the classic government funding route, while Blue Origin has a billionaire owner who can act lightning-fast – the two companies’ situations do not favor Aerojet Rocketdyne.

“Compare it to having two fiancées, two possible brides,” Tobey said of ULA’s approach to the two. “Blue Origin is a super-rich girl, and then there is this poor girl over here, Aerojet Rocketdyne. But we have to continue to go to planned rehearsal dinners, buy cakes and all the rest with both.

“We’re doing all the work on both, and the chance of Aerojet Rocketdyne beating the billionaire is pretty low. Basically we’re putting a whole lot more energy into BE-4 for Blue Origin.”

Using methane would be new for the U.S. space sector, imposing risks, but Tobey said the BE-4 engine is only 60 percent of the cost of the AR1, a clear advantage in today’s cost-driven market.

Of both engines, he said: “They are never going to outperform the RD-180."

http://spacenews.com/ula-intends-to-lower-its-costs-and-raise-its-cool-to-compete-with-spacex/ (http://spacenews.com/ula-intends-to-lower-its-costs-and-raise-its-cool-to-compete-with-spacex/)
Title: Re: Blue Origin's BE-4 Engine
Post by: pippin on 08/09/2016 01:14 PM
I think people underappreciate how good RD-180 is. I'm not sure the US (except maybe for AJR due to the license) has the technology to build an engine with similar performance let alone a relative newcomer like BO.
And the difference in ISP between methane and kerosene isn't very big. Actually, almost all methane engine designs proposed so far had lower ISP than high-ISP kerosene engines, probably due to less experience with the fuel. I'm not sure the high-pressure combustion behavior is as well understood as for kerosene and hydrogen
Title: Re: Blue Origin's BE-4 Engine
Post by: Robotbeat on 08/09/2016 01:34 PM
I dislike "performance." If you mean Isp, say Isp. If you mean T/W ratio, say T/W ratio.

On the latter, Merlin 1D kicks RD180's butt all over town. Merlin 1D with recent thrust upgrades gets T/W of 200.
Title: Re: Blue Origin's BE-4 Engine
Post by: baldusi on 08/09/2016 01:48 PM
I dislike "performance." If you mean Isp, say Isp. If you mean T/W ratio, say T/W ratio.

On the latter, Merlin 1D kicks RD180's butt all over town. Merlin 1D with recent thrust upgrades gets T/W of 200.
Well, Merlin 1D is sort of an outlier in the T/W business. Before it, the RD-180 was up there as the best T/W (don't believe the NK-33 numbers published elsewhere, they don't include the TVC). But you can't forget the fact that the RD-170 was commissioned by 1985. And the RD-180 was flying by 2000, with Russian manufacturing technology of the 80s. In fact, the thing I find most impressive is that people says that the tolerances on that engine are ridiculously loose.
Title: Re: Blue Origin's BE-4 Engine
Post by: Jim on 08/09/2016 01:58 PM
I dislike "performance." If you mean Isp, say Isp. If you mean T/W ratio, say T/W ratio.

On the latter, Merlin 1D kicks RD180's butt all over town. Merlin 1D with recent thrust upgrades gets T/W of 200.

Not a really relevant parameter for comparison. Try installed T/W.  Compare Atlas V thrust section to F9 thrust section.  Installation wise, I bet RD-180 kick Merlins butt all over town.  Atlas V/RD-180 had no need for 9 feed lines.
Title: Re: Blue Origin's BE-4 Engine
Post by: ugordan on 08/09/2016 02:02 PM
In fact, the thing I find most impressive is that people says that the tolerances on that engine are ridiculously loose.

Yet several years ago there were people on here calling RD-180 a "ticking time bomb". Whether it was due to its ox-rich staged combustion cycle, a distrust toward its country of origin and their manufacturing practices and whether it was coming from experts in the field or forum "experts", I don't know, but it was pretty amusing.
Title: Re: Blue Origin's BE-4 Engine
Post by: rpapo on 08/09/2016 02:10 PM
Not a really relevant parameter for comparison. Try installed T/W.  Compare Atlas V thrust section to F9 thrust section.  Installation wise, I bet RD-180 kick Merlins butt all over town.  Atlas V/RD-180 had no need for 9 feed lines.
But they can't throttle down to what is effectively less than 10% thrust either.  Yes, I appreciate the KISS principle in rocket design, but they could never have pulled off the booster landings with only one or two very powerful engines.
Title: Re: Blue Origin's BE-4 Engine
Post by: Robotbeat on 08/09/2016 02:15 PM
I dislike "performance." If you mean Isp, say Isp. If you mean T/W ratio, say T/W ratio.

On the latter, Merlin 1D kicks RD180's butt all over town. Merlin 1D with recent thrust upgrades gets T/W of 200.

Not a really relevant parameter for comparison. Try installed T/W.  Compare Atlas V thrust section to F9 thrust section.  Installation wise, I bet RD-180 kick Merlins butt all over town.  Atlas V/RD-180 had no need for 9 feed lines.
I'd take that wager.
Title: Re: Blue Origin's BE-4 Engine
Post by: Jim on 08/09/2016 02:21 PM
Not a really relevant parameter for comparison. Try installed T/W.  Compare Atlas V thrust section to F9 thrust section.  Installation wise, I bet RD-180 kick Merlins butt all over town.  Atlas V/RD-180 had no need for 9 feed lines.
But they can't throttle down to what is effectively less than 10% thrust either.  Yes, I appreciate the KISS principle in rocket design, but they could never have pulled off the booster landings with only one or two very powerful engines.

Neither can Merlin.  But what does throttling or landing have to do with the BE-4?
Title: Re: Blue Origin's BE-4 Engine
Post by: rpapo on 08/09/2016 02:53 PM
Not a really relevant parameter for comparison. Try installed T/W.  Compare Atlas V thrust section to F9 thrust section.  Installation wise, I bet RD-180 kick Merlins butt all over town.  Atlas V/RD-180 had no need for 9 feed lines.
But they can't throttle down to what is effectively less than 10% thrust either.  Yes, I appreciate the KISS principle in rocket design, but they could never have pulled off the booster landings with only one or two very powerful engines.

Neither can Merlin.  But what does throttling or landing have to do with the BE-4?
I wasn't speaking of the BE-4 at all (and therefore was off topic).  I was referring to your comment about the greater plumbing requirements for the Merlin, or rather for the set of nine of them.  Their use case is different, so the comparison is not entirely fair.
Title: Re: Blue Origin's BE-4 Engine
Post by: Robotbeat on 08/09/2016 02:55 PM
Not a really relevant parameter for comparison. Try installed T/W.  Compare Atlas V thrust section to F9 thrust section.  Installation wise, I bet RD-180 kick Merlins butt all over town.  Atlas V/RD-180 had no need for 9 feed lines.
But they can't throttle down to what is effectively less than 10% thrust either.  Yes, I appreciate the KISS principle in rocket design, but they could never have pulled off the booster landings with only one or two very powerful engines.

Neither can Merlin.  But what does throttling or landing have to do with the BE-4?
It was originally developed for Blue Origin's own vehicle. The deal with ULA came after.
Title: Re: Blue Origin's BE-4 Engine
Post by: Oli on 08/09/2016 04:26 PM
Actually, almost all methane engine designs proposed so far had lower ISP than high-ISP kerosene engines

I don't think so, which ones?
Title: Re: Blue Origin's BE-4 Engine
Post by: Dante80 on 08/09/2016 04:37 PM
Not a really relevant parameter for comparison. Try installed T/W.  Compare Atlas V thrust section to F9 thrust section.  Installation wise, I bet RD-180 kick Merlins butt all over town.  Atlas V/RD-180 had no need for 9 feed lines.

Even if you account for the extra weight for more feed lines and such, the thrust assembly should still be lighter (per kN installed). And we are talking about double the thrust here as per the coming uprate (so you would have to compare the assembly with something like the RD-171 based Zenit assembly).

The public info I have for RD-180 is a weight of 5,480 kg, and for the 9 Merlins the weight is around 4,230 kg with the actuators installed.
Title: Re: Blue Origin's BE-4 Engine
Post by: baldusi on 08/09/2016 04:42 PM
In fact, the thing I find most impressive is that people says that the tolerances on that engine are ridiculously loose.

Yet several years ago there were people on here calling RD-180 a "ticking time bomb". Whether it was due to its ox-rich staged combustion cycle, a distrust toward its country of origin and their manufacturing practices and whether it was coming from experts in the field or forum "experts", I don't know, but it was pretty amusing.
Those were the MSFC that used that to dismiss anything not done by them (actually, their contractors under their supervision). That's how they stated with a straight face that Atlas V was risky while Ares I was the safest ever. Look what happened when they were taken out and the industry was left to decide.
Some went with gas generator (Space), but the rest went with ORSC. In fact, for the next step, SpaceX and KBKhA went with gas-gas implementations. There is a reason BE-4 is that, when it could have been fuel rich, for example.
Yes, the expansive energy of an ORSC turbine failure is something like 20 to 50 times that of a gas generator. But propulsion failure is LOM if you don't have engine out capabilities (and in many cases, even engine out won't cut it). No matter how "minimal" the catastrophic failure. LAS will (quite probably) save your crew exactly the same as long as the engine is turned off.
So I don't pay much attention to those naysayers. The rocket technology wars have a clear winner and the hero of that battle was the RD-180. BE-4 is probably more indebted to the RD-170 than to any other engine family.
Title: Re: Blue Origin's BE-4 Engine
Post by: notsorandom on 08/09/2016 06:53 PM
Please correct me if I'm wrong but haven't the various proposed Russian crew launch vehicle using the RD-170 family engines lowered the chamber pressure to increase safety?
Title: Re: Blue Origin's BE-4 Engine
Post by: baldusi on 08/10/2016 12:17 AM
Please correct me if I'm wrong but haven't the various proposed Russian crew launch vehicle using the RD-170 family engines lowered the chamber pressure to increase safety?
The RD-180V when it was designed for the Rus-M, used lower pressures. But that was due to the worse particle cleanness standard for the tanks on the Russian industry. The Atlas V version only added electronics for extra fault detection.
In fact, the RD-191 actually increased it so slightly. And RD-181 is actually same as RD-191. So they sort of increased it. Yes, the RD-0162/4 (KBKhA project) used lower chamber pressure. But was quite an increased when compared to previous models of the design bureau. And I'm kind of suspect of Voronezh's quality wrt NPO Energomash.
Title: Re: Blue Origin's BE-4 Engine
Post by: Steven Pietrobon on 08/10/2016 06:19 AM
Regarding BE-4, here is what we know so far.

Propellants: LNG/LOX
Thrust: ~ 550,000 lbf
Chamber pressure: 1,950 psi
Cycle: ORSC (single shaft)
Isp:<311s SL, <338 vac. (for the booster variant in Vulcan)
TWR: <78
Re-usability: 25 complete missions, minimum.

If sea level thrust Fs = 2446.5 kN and the exit diameter of the BE-4 is De = 1.886 m (as measured from posted drawings), then the vacuum thrust is Fv = Fs + π De²/4 Pa = 2729.6 kN where Pa = 101.325 kPa is the sea level surface pressure. This means that if the Sea Level Isp is Is = 311 s, then the vacuum Isp must be Iv = Is*Fv/Fs = 347 s, quite a bit higher than the RD-180.

Using Pc = 13,445 kPa, an area ratio of Ar = (1.886/0.4)² = 22.22 and nozzle efficiency of 0.9418 (the same as the RD-180), the USAF Isp program gives an Iv = 337 s and Is = 302 s, which is less than the RD-180 with Iv = 338.4 s and Is = 311.9 s.
Title: Re: Blue Origin's BE-4 Engine
Post by: Space Ghost 1962 on 08/29/2016 05:48 PM
Suggest that a full scale Raptor on a test stand is within a month or so.

Have not heard Bezos brag about a full scale BE4 making it to a test stand, is he behind Musk?

Will Musk beat Bezos to the test stand with a engine for respective next vehicles?

Pretty sure AR1 is at least 18+ months out and not sweating.

Can anyone contradict this please?

Oh, and could we somewhere do an engine comparative between the three and their best known stats. Thank you.
Title: Re: Blue Origin's BE-4 Engine
Post by: jongoff on 08/29/2016 10:39 PM
Suggest that a full scale Raptor on a test stand is within a month or so.

Have not heard Bezos brag about a full scale BE4 making it to a test stand, is he behind Musk?

Will Musk beat Bezos to the test stand with a engine for respective next vehicles?

Pretty sure AR1 is at least 18+ months out and not sweating.

Can anyone contradict this please?

Oh, and could we somewhere do an engine comparative between the three and their best known stats. Thank you.

Do we have more details on this Raptor engine going to the test stands than the one sentence from Gwynne's SmallSat talk? I know people are interpreting this as a fully-integrated, flight-like Raptor engine, but has SpaceX actually said that, or are we possibly reading things into that statement that they never explicitly claimed.

As for BE-4 status, I think the goal was to have the full-scale engine into testing this year, so ULA could make a downselect decision between AR-1/BE-4.

It's possible that SpaceX has caught up and passed Blue Origin with Raptor, but we're basing a lot off of a single sentence from a talk (unless there've been more details released since then).

~Jon
Title: Re: Blue Origin's BE-4 Engine
Post by: scanline on 09/06/2016 05:46 AM
http://www.parabolicarc.com/2016/03/11/be4-engine-testing-update-jeff-bezos/

Apologies in advance if I'm in the wrong place.
That looks like a thrust plate, while Merlin is a pintle.  I didn't find any information about what Raptor has.
Is it possible to do staged combustion with a pintle?
Thanks!

Title: Re: Blue Origin's BE-4 Engine
Post by: Steven Pietrobon on 09/06/2016 06:06 AM
Is it possible to do staged combustion with a pintle?

I don't see why not. Using a pintle is a method of injecting the propellants into the combustion chamber. Staged combustion is a method of pressuring the propellants before injection. I would have thought those two operations (injection and pressurisation) would be fairly independent of the method used.
Title: Re: Blue Origin's BE-4 Engine
Post by: Nomic on 09/06/2016 08:22 AM
Apologies in advance if I'm in the wrong place.
That looks like a thrust plate, while Merlin is a pintle.  I didn't find any information about what Raptor has.
Is it possible to do staged combustion with a pintle?
Thanks!

Don't think the current Merlin has a pintle injector. Could be wrong but pintles don't work to well with high chamber pressures (1000+ psi?), too much prop hitting the side wall leading to hot spot on the chamber wall. Suppose could get round this with greater local cooling, transpiration/film etc. Also seem to remember there was some IP issues with Mr Muellers former employer, so they switched to some variant of coax swirl.
Title: Re: Blue Origin's BE-4 Engine
Post by: baldusi on 09/06/2016 05:59 PM
http://www.parabolicarc.com/2016/03/11/be4-engine-testing-update-jeff-bezos/

Apologies in advance if I'm in the wrong place.
That looks like a thrust plate, while Merlin is a pintle.  I didn't find any information about what Raptor has.
Is it possible to do staged combustion with a pintle?
Thanks!
One characteristic of Raptor is that it is a full flow cycle. Thus, it needs three injectors: LOX-rich preburner, CH4-rich preburner and Main Combustion chamber preburner.
The preburners need to mix two liquids, but have a very un balance ratio (sometimes 50:1 O/F). When Muller worked on the TR-107 (I think), he used a pintle on the ORSC preburner (the RP-1 was injected in liquid form). So I would speculate that both preburners are pintle injectors.
Regarding the MCC injector, that's anybody's guess. Pintle should work fine, you are working with hot gases, so mixing should be a lot easier than with liquids. And the inertia is a lot less, too. But you need a big section because gas is a lot less dense than liquid (depending staged combustion on pressure 2 to 8 times less). Without knowing the subject, I would get the impression that Raptor could use pintle just fine.
But Raptor will also use a lot of 3D printing. Pintle are beautiful for machining on a lathe. But 3D printing is better suited for coaxial injectors.
In the end, it is anybody's guess, for now.
Title: Re: Blue Origin's BE-4 Engine
Post by: baldusi on 09/06/2016 06:01 PM
Apologies in advance if I'm in the wrong place.
That looks like a thrust plate, while Merlin is a pintle.  I didn't find any information about what Raptor has.
Is it possible to do staged combustion with a pintle?
Thanks!

Don't think the current Merlin has a pintle injector. Could be wrong but pintles don't work to well with high chamber pressures (1000+ psi?), too much prop hitting the side wall leading to hot spot on the chamber wall. Suppose could get round this with greater local cooling, transpiration/film etc. Also seem to remember there was some IP issues with Mr Muellers former employer, so they switched to some variant of coax swirl.
As far as I understand it, you just have to change the mixing angle somewhat to take into consideration the higher pressure. And I think that the IP issues were resolved the old fashion way (i.e. licensing).
Title: Re: Blue Origin's BE-4 Engine
Post by: Nomadd on 09/06/2016 06:19 PM
 I remember in the beginning, Musk wasn't too happy with the combustion efficiency with the "bloody pintle"
Title: Re: Blue Origin's BE-4 Engine
Post by: mheney on 09/06/2016 07:37 PM
Let's keep this on the BE-4.  There are plenty of other places for discussing SpaceX engines ...
Title: Re: Blue Origin's BE-4 Engine
Post by: baldusi on 09/07/2016 01:10 AM
Well, I wonder if they used a pintle injector in the preburner. Simplest, cheapest and most reliable.
Title: Re: Blue Origin's BE-4 Engine
Post by: Nomic on 09/07/2016 08:59 AM
Pintle preburner, interesting. The CFD picture they released of the preburner in their mailing list looked more "traditional" and text with it talked about injector elements. Along RD-170 lines, swirl injectors burning at normal mixture rations then diluted with extra oxygen. Assuming the picture is representative of what they are really working on of course.
Title: Re: Blue Origin's BE-4 Engine
Post by: baldusi on 09/07/2016 08:04 PM
Pintle preburner, interesting. The CFD picture they released of the preburner in their mailing list looked more "traditional" and text with it talked about injector elements. Along RD-170 lines, swirl injectors burning at normal mixture rations then diluted with extra oxygen. Assuming the picture is representative of what they are really working on of course.
Quite probable that they are pretty standard, then.
Title: Re: Blue Origin's BE-4 Engine
Post by: AncientU on 09/13/2016 12:22 AM
Not a really relevant parameter for comparison. Try installed T/W.  Compare Atlas V thrust section to F9 thrust section.  Installation wise, I bet RD-180 kick Merlins butt all over town.  Atlas V/RD-180 had no need for 9 feed lines.
But they can't throttle down to what is effectively less than 10% thrust either.  Yes, I appreciate the KISS principle in rocket design, but they could never have pulled off the booster landings with only one or two very powerful engines.

Neither can Merlin.  But what does throttling or landing have to do with the BE-4?

Everything it seems...
Title: Re: Blue Origin's BE-4 Engine
Post by: ZachF on 09/24/2016 07:15 PM
I dislike "performance." If you mean Isp, say Isp. If you mean T/W ratio, say T/W ratio.

On the latter, Merlin 1D kicks RD180's butt all over town. Merlin 1D with recent thrust upgrades gets T/W of 200.

Not a really relevant parameter for comparison. Try installed T/W.  Compare Atlas V thrust section to F9 thrust section.  Installation wise, I bet RD-180 kick Merlins butt all over town.  Atlas V/RD-180 had no need for 9 feed lines.

I doubt it. The empty mass of a Falcon 9FT first stage is listed at 25,600 kg and it produces 5,886kN of thrust at sea level. The Atlas V first stage weighs 21,054kg empty and makes 3,827kN of thrust. So the empty thrust/weight ratio is 26.5% better on the Falcon 9 than the Atlas V. Of course, the empty Falcon 9FT stage also includes around 2,500kg of landing equipment.... and it holds more propellent (395,700kg vs 284,089kg)

So, if we take away the 2,500kg of landing equipment, The Falcon 9FT first stage weighs ~10% more, yet produces 54% more thrust, and holds 39% more fuel.
Title: Re: Blue Origin's BE-4 Engine
Post by: ZachF on 09/24/2016 08:04 PM
Not a really relevant parameter for comparison. Try installed T/W.  Compare Atlas V thrust section to F9 thrust section.  Installation wise, I bet RD-180 kick Merlins butt all over town.  Atlas V/RD-180 had no need for 9 feed lines.
But they can't throttle down to what is effectively less than 10% thrust either.  Yes, I appreciate the KISS principle in rocket design, but they could never have pulled off the booster landings with only one or two very powerful engines.

Neither can Merlin.  But what does throttling or landing have to do with the BE-4?

Everything it seems...

Merlin can't throttle down to <10% thrust but the Falcon 9 can by shutting off 8 of its 9 engines.

7 engines probably works out well for a Methalox stage because the relative empty mass for a stage with less-dense fuel will be higher (thus requiring more thrust to stop), and the T:W ratio of the engines will likely be lower.

A NG first stage will probably weigh ~80,000 kg (176,000lbs, roughly 60% of what a Saturn V first stage weighs) with BE-4 producing 550,000lbs of thrust that gives a landing empty stage a T:W of around 3. Falcon 9 stage weighs 25,600kg (56,320lbs) and one merlin produces ~165,000 lbs of thrust, also giving an empty stage T:W on one engine of around 3.
Title: Re: Blue Origin's BE-4 Engine
Post by: ZachF on 09/24/2016 08:09 PM
I dislike "performance." If you mean Isp, say Isp. If you mean T/W ratio, say T/W ratio.

On the latter, Merlin 1D kicks RD180's butt all over town. Merlin 1D with recent thrust upgrades gets T/W of 200.

Not a really relevant parameter for comparison. Try installed T/W.  Compare Atlas V thrust section to F9 thrust section.  Installation wise, I bet RD-180 kick Merlins butt all over town.  Atlas V/RD-180 had no need for 9 feed lines.

I doubt it. The empty mass of a Falcon 9FT first stage is listed at 25,600 kg and it produces 5,886kN of thrust at sea level. The Atlas V first stage weighs 21,054kg empty and makes 3,827kN of thrust. So the empty thrust/weight ratio is 26.5% better on the Falcon 9 than the Atlas V. Of course, the empty Falcon 9FT stage also includes around 2,500kg of landing equipment.... and it holds more propellent (395,700kg vs 284,089kg)

So, if we take away the 2,500kg of landing equipment, The Falcon 9FT first stage weighs ~10% more, yet produces 54% more thrust, and holds 39% more fuel.

Seems the FT produces 6,570kN of thrust not 5,886kN, so it's even less likely.
Title: Re: Blue Origin's BE-4 Engine
Post by: Chris Bergin on 09/25/2016 12:08 PM
Ho ho. Let's drag this back to BE-4 please.
Title: Re: Blue Origin's BE-4 Engine
Post by: Lemurion on 10/01/2016 06:20 PM
I'm wondering if Blue has already penciled in the BE-4 for the New Armstrong, and if so what that says about its projected capabilities? I was originally expecting New Armstrong to compare to ITS, but if it sticks with BE-4 I'm not sure that it's a reasonable expectation.
Title: Re: Blue Origin's BE-4 Engine
Post by: DJPledger on 10/02/2016 01:46 PM
I'm wondering if Blue has already penciled in the BE-4 for the New Armstrong, and if so what that says about its projected capabilities? I was originally expecting New Armstrong to compare to ITS, but if it sticks with BE-4 I'm not sure that it's a reasonable expectation.
BO need to dev. a FFSC engine for NA for it to have any chance of competing with ITS. BE-4 performance sucks compared to Raptor.
Title: Re: Blue Origin's BE-4 Engine
Post by: TrevorMonty on 10/02/2016 02:47 PM
The BE4 was designed to be reuseable and low cost to build, to achieve this Blue went for design that had moderate performance.

Blue have BE3 for BLEO missions so BE4 doesn't need great ISP vac. If moon is your near term goal LH is better fuel as missions are measured in days not months.
Title: Re: Blue Origin's BE-4 Engine
Post by: b0objunior on 10/02/2016 05:37 PM
The BE4 was designed to be reuseable and low cost to build, to achieve this Blue went for design that had moderate performance.

Blue have BE3 for BLEO missions so BE4 doesn't need great ISP vac. If moon is your near term goal LH is better fuel as missions are measured in days not months.
And there not CO2 on the moon, so making methane is out of the question.
Title: Re: Blue Origin's BE-4 Engine
Post by: DJPledger on 10/02/2016 06:34 PM
The BE4 was designed to be reuseable and low cost to build, to achieve this Blue went for design that had moderate performance.

Blue have BE3 for BLEO missions so BE4 doesn't need great ISP vac. If moon is your near term goal LH is better fuel as missions are measured in days not months.
Raptor is also designed to be reuseable and low cost. If BE-4 was designed to be FFSC then it could have competed with Raptor on performance. BO missed a trick by only going with ORSC and not FFSC with BE-4. Not to mention that FFSC eliminates the interpropellant seal which removes a major failure mode. FFSC also allows you to dev. a smaller engine of comparable thrust than with ORSC. Just compare the physical sizes of BE-4 and Raptor. Raptor is physically smaller than BE-4 yet is more powerful.

If NA has the same dia. as ITS booster and uses BE-4's then you won't be able to put anywhere near the amount of thrust under it as the ITS booster.
Title: Re: Blue Origin's BE-4 Engine
Post by: b0objunior on 10/02/2016 07:01 PM
The BE4 was designed to be reuseable and low cost to build, to achieve this Blue went for design that had moderate performance.

Blue have BE3 for BLEO missions so BE4 doesn't need great ISP vac. If moon is your near term goal LH is better fuel as missions are measured in days not months.
Raptor is also designed to be reuseable and low cost. If BE-4 was designed to be FFSC then it could have competed with Raptor on performance. BO missed a trick by only going with ORSC and not FFSC with BE-4. Not to mention that FFSC eliminates the interpropellant seal which removes a major failure mode. FFSC also allows you to dev. a smaller engine of comparable thrust than with ORSC. Just compare the physical sizes of BE-4 and Raptor. Raptor is physically smaller than BE-4 yet is more powerful.

If NA has the same dia. as ITS booster and uses BE-4's then you won't be able to put anywhere near the amount of thrust under it as the ITS booster.
We get it, we are not idiots. The BE-4 is not as good as raptor on certain aspects. But I don't have a crystal ball, the future is not set.
Title: Re: Blue Origin's BE-4 Engine
Post by: Chasm on 10/02/2016 07:51 PM
Dropping everything for a FFSC engine? Ultimatly? Probably. Right now? I don't think so.

Right now Blue has to get BE-4 working and delivered. With high reliability and high confidence in said reliability. Meeting all the contracted performance, quantity, price and operations cost. The worst thing they could do is one of these two: Not to deliver the engines they sold. Delivering firecrackers. Vulcan does not exactly have engine out capability.

We don't know at this time how good or bad BE-4 actually is. ULA should have an idea about BE-4 and Blue should have know, given all the talk about poaching SpaceX engine developers, where Raptor was going.


BE-4 is still slated to be one of the more efficient engines worldwide, both on performance and price.
Title: Re: Blue Origin's BE-4 Engine
Post by: Space Ghost 1962 on 10/02/2016 07:56 PM
Keep in mind Raptor has fired on a test stand.

What if BE4 slips and doesn't make it to a test stand?

Already, in theory, a Raptor based Vulcan a)might make it to a pad faster/cheaper, b) might have greater payload to orbit, and c) might be more reliable.

That is the strategic position at the moment. No tactical course to accept this as an option.
Title: Re: Blue Origin's BE-4 Engine
Post by: b0objunior on 10/02/2016 07:59 PM
Keep in mind Raptor has fired on a test stand.

What if BE4 slips and doesn't make it to a test stand?

Already, in theory, a Raptor based Vulcan a)might make it to a pad faster/cheaper, b) might have greater payload to orbit, and c) might be more reliable.

That is the strategic position at the moment. No tactical course to accept this as an option.

All baseless assumptions. There's speculting and SPECULATING.
Title: Re: Blue Origin's BE-4 Engine
Post by: TrevorMonty on 10/02/2016 08:00 PM
There is no competution between Raptor and BE4. Raptor will never be sold to another LV company. The LVs these engines are used may well compete for same payloads. The engines costs especially if used in RLV will be small part of launch price.


Title: Re: Blue Origin's BE-4 Engine
Post by: Space Ghost 1962 on 10/02/2016 08:07 PM
Keep in mind Raptor has fired on a test stand.

What if BE4 slips and doesn't make it to a test stand?

Already, in theory, a Raptor based Vulcan a)might make it to a pad faster/cheaper, b) might have greater payload to orbit, and c) might be more reliable.

That is the strategic position at the moment. No tactical course to accept this as an option.

All baseless assumptions. There's speculting and SPECULATING.
Specifics? Or just your "feelings"?

There is no competution between Raptor and BE4. Raptor will never be sold to another LV company. The LVs these engines are used may well compete for same payloads. The engines costs especially if used in RLV will be small part of launch price.
Part of any AF money (like Raptor got) comes with the requirement that AF might be able to have a means to use it.

They are both methalox. They are both booster engines. And at this stage in development, yes both can be used.
Title: Re: Blue Origin's BE-4 Engine
Post by: b0objunior on 10/02/2016 09:15 PM
Quote
Keep in mind Raptor has fired on a test stand.

What if BE4 slips and doesn't make it to a test stand?

Already, in theory, a Raptor based Vulcan a)might make it to a pad faster/cheaper, b) might have greater payload to orbit, and c) might be more reliable.

That is the strategic position at the moment. No tactical course to accept this as an option.
Quote
All baseless assumptions. There's speculting and SPECULATING.
Quote
Specifics? Or just your "feelings"?
The specifics, we have no clue about where Vulcan is or it's future. If upgrading to Raptor is even possible considering the increased trust.
Title: Re: Blue Origin's BE-4 Engine
Post by: Space Ghost 1962 on 10/02/2016 09:43 PM
Quote
Keep in mind Raptor has fired on a test stand.

What if BE4 slips and doesn't make it to a test stand?

Already, in theory, a Raptor based Vulcan a)might make it to a pad faster/cheaper, b) might have greater payload to orbit, and c) might be more reliable.

That is the strategic position at the moment. No tactical course to accept this as an option.
Quote
All baseless assumptions. There's speculting and SPECULATING.
Quote
Specifics? Or just your "feelings"?
The specifics, we have no clue about where Vulcan is or it's future. If upgrading to Raptor is even possible considering the increased trust.

No, we have a great deal of insight on Vulcan and it's choice of BE4, as well as the potential "fall back" of AR1.

Immediately we already know:
 + That Vulcan at this point is "adaptable to engines" (source: Tory Bruno)
 + That Vulcan can have methalox props (sources: ULA, BO)
 + That Vulcan's final design will be adjusted to the performance of engines, both thrust and iSP (source: Tory Bruno, on explaining BE4 preference)
 + That Raptor's specs (source: SX) approach closer to the RD180 (source: ULA) than expected BE4 (source: BO)

Does not mean they will do it. Just means that they add risk by not considering it. On a risk reduction project, meant to replace foreign engine sourcing.

But, then, you now, it's not about engineering, just good old fashion politics. With the pretense of "better".

Just like in Russia.
Title: Re: Blue Origin's BE-4 Engine
Post by: leaflion on 10/02/2016 11:30 PM
Dropping everything for a FFSC engine? Ultimatly? Probably. Right now? I don't think so.

Right now Blue has to get BE-4 working and delivered. With high reliability and high confidence in said reliability. Meeting all the contracted performance, quantity, price and operations cost. The worst thing they could do is one of these two: Not to deliver the engines they sold. Delivering firecrackers. Vulcan does not exactly have engine out capability.

We don't know at this time how good or bad BE-4 actually is. ULA should have an idea about BE-4 and Blue should have know, given all the talk about poaching SpaceX engine developers, where Raptor was going.


BE-4 is still slated to be one of the more efficient engines worldwide, both on performance and price.

Not to mention BE-4's much lower chamber pressure gives a lot more confidence in its potential reliability. Starting immediately with the highest chamber pressure engine we've seen in a long time is not a great recipe for reliability.  One way of dealing with that is by designing your LV to not care, but when you are selling engines its hard to say, "yeah, every 50th one fails, but we think that's good enough."

While FFSC removes the IPS, it also has 1 more combuster to fail.  Take your pick, seal or combuster. When is the last time an engine failed from its IPS?

Do we know if the turbomachinery was part of that Raptor test?  The Raptor thread is too long for me to pick through and try to figure it out.  The lack of details from SpaceX lead me to believe it didn't, but this is just speculation.
Title: Re: Blue Origin's BE-4 Engine
Post by: hkultala on 10/02/2016 11:45 PM
I'm wondering if Blue has already penciled in the BE-4 for the New Armstrong, and if so what that says about its projected capabilities? I was originally expecting New Armstrong to compare to ITS, but if it sticks with BE-4 I'm not sure that it's a reasonable expectation.
BO need to dev. a FFSC engine for NA for it to have any chance of competing with ITS.
 BE-4 performance sucks compared to Raptor.

... and any kerosine engine sucks on isp if compared to RD-170 series.
... and most kerosine engins suck in paper if compared with NK-33. (if that nk-33 would just work reliably..)


The ONLY known numbers about BE-4 are chamber pressure(and that may increase with future versions of the engine) and a rough estimate about thrust range.
isp is not known(though we know that it will be less than raptor isp due less pressure). Actual final thrust is not known. Weight is not known. => T/W is not known. Manufacturing cost is not known.

Saying that is sucks without knowing anything is really childish. It may be cheaper to manufacture. It may have better T/W(thought this seems impropable). It may end up being more reliable.


What can be said is that BE-4 is less advanced engine than Raptor. Just like Merlin is less advanced than RD-180, but F9 still gives much better bang/buck than Atlas V, and mostly BECAUSE of the less advanced engine, not in spite of it.



Title: Re: Blue Origin's BE-4 Engine
Post by: edkyle99 on 10/03/2016 12:27 AM
Not to mention BE-4's much lower chamber pressure gives a lot more confidence in its potential reliability.
I agree.  Reliability, not ISP or any other number, will largely determinate if these engines make the history texts or merely the footnotes. 

 - Ed Kyle
Title: Re: Blue Origin's BE-4 Engine
Post by: Space Ghost 1962 on 10/03/2016 12:43 AM
Not to mention BE-4's much lower chamber pressure gives a lot more confidence in its potential reliability.
I agree.  Reliability, not ISP or any other number, will largely determinate if these engines make the history texts or merely the footnotes. 

Reliability has nothing to do with confidence. Reliability is an intrinsic in a manufactured design that is proven on a test stand and confirmed with tear down and measurement. Over and over again. Test history. Flight history. Revisions.

Nothing you determine in the short term.
Title: Re: Blue Origin's BE-4 Engine
Post by: arachnitect on 10/03/2016 02:18 AM
Not to mention BE-4's much lower chamber pressure gives a lot more confidence in its potential reliability.
I agree.  Reliability, not ISP or any other number, will largely determinate if these engines make the history texts or merely the footnotes. 

Reliability has nothing to do with confidence. Reliability is an intrinsic in a manufactured design that is proven on a test stand and confirmed with tear down and measurement. Over and over again. Test history. Flight history. Revisions.

Nothing you determine in the short term.


...and there is little test history -and no flight history- of FFSC engines.
Title: Re: Blue Origin's BE-4 Engine
Post by: Dante80 on 10/03/2016 02:29 AM


...and there is little test history -and no flight history- of FFSC engines.

Yes. And the same is true more or less for large methalox ORSC engines.

In the end though, one thing for me is clear. Raptor will be completed later than BE-4, and will probably also have a more complex and arduous development program. I get the vibe that Raptor is designed like a Ferrari, and  BE-4 like a Hummer... ;)

Not that it matters really. Both engines are designed for mass production, and hopefully both are going to have long and successful histories (fingers crossed). Those comparison stories (my rocket engine is better than yours!) are pretty boring I think.
 
Title: Re: Blue Origin's BE-4 Engine
Post by: baldusi on 10/03/2016 03:44 PM
I don't believe that BE-4 was developed to Raptor's specifications. Also, we have companies that have lasted a 100 years exactly for avoiding the bleeding edge (e.g. Ford). I love Raptor's technology, but I wouldn't presume to know how the future will develop just because one technology appears superior to the other.
In fact, if you asked me which engine could be the best step to make a Raptor engine, I would say that BE-4 is quite probably the best bet. You have things like the RD-0164, that could probably match Raptor.
But KBKhA had a lot of experience on the expander cycle and ORSC. Only Aerojet Rocketdyne had that experience, and they wouldn't even start to think about something like that without a 3B contract from the US Government.
Title: Re: Blue Origin's BE-4 Engine
Post by: Oli on 10/03/2016 05:08 PM
BO said it's doing a medium performance version of a high performance architecture. For reliability/reusability. SpaceX does a very high performance version of a very high performance architecture.

By the way, do we know why BO chose ORSC? It seems they want to avoid FRSC, which would preclude a FFSC architecture.
Title: Re: Blue Origin's BE-4 Engine
Post by: baldusi on 10/03/2016 05:16 PM
BO said it's doing a medium performance version of a high performance architecture. For reliability/reusability. SpaceX does a very high performance version of a very high performance architecture.

By the way, do we know why BO chose ORSC? It seems they want to avoid FRSC, which would preclude a FFSC architecture.

Well, the decision is very easy from a thermodynamics POV. The power to your turbines is (basically) specific heat * mass flow. Do the numbers for methalox and you get more power with ORSC. They wanted a cheap engine, and so they went with a single turbine.
Nothing prevents them from then developing a full flow engine on that base. In fact, it would be "relatively" easy. The FRSC circuit is the easiest.
Title: Re: Blue Origin's BE-4 Engine
Post by: Space Ghost 1962 on 10/03/2016 08:24 PM
Not to mention BE-4's much lower chamber pressure gives a lot more confidence in its potential reliability.
I agree.  Reliability, not ISP or any other number, will largely determinate if these engines make the history texts or merely the footnotes. 

Reliability has nothing to do with confidence. Reliability is an intrinsic in a manufactured design that is proven on a test stand and confirmed with tear down and measurement. Over and over again. Test history. Flight history. Revisions.

Nothing you determine in the short term.


...and there is little test history -and no flight history- of FFSC engines.
True also for the SSME when it was chosen for the Shuttle.

As for the RD270, 24 tests of (I think) 7 engines. Was at the time the most powerful engine on Earth.

Did not continue because the huge (super Proton) LV it was designed for was discontinued. In favor of N1, out of fear of a launch catastrophe for so much hypergolic propellant.

Oh, yeah BE-4 and AR-1 are first American ORSC engines too here. No American ORSC engines have ever been flown.

And ... some claim that FFSC, while more complex, is less risky because your dual preburner sides of the closed loop can be smaller and run at a lower relative pressure. So the true risk is in the injectors/combustion chamber.

If you have recent experience upping same in a prior engine, perhaps this is not such a big deal?

However, if you're dependent on materials technology to hold up for ORSC, it might take a while to perfect the recipe to reach enough of a preburner flow rate to match enough of a chamber pressure, without your parts being consumed in the process? The NK33 had considerable teething pains, along with its follow-on.

Have to consider ... what to be relentless about ... to achieve a reliable engine.

add:

Don't think I've ever been aware of any engine program ... that ever set out to design an unreliable engine  ::)

Would also think, that if you needed to gang large numbers of them together, rely on them for HSF, and require them to function with reuse, performing a function similar to the LM Ascent engine ... that reliability would be a significant requirement  :o

RS68's (and Merlin 1A) had ablative nozzles. As such, expendible limited life components ... so you might say limited reliability yield, I suppose ...

add:

Afraid we'll never know the truth about NK-33's reliability. Too much has happened to obscure it. And it appears to be in no one's interest to clarify that which remains to any great degree. Too many half truths ...
Title: Re: Blue Origin's BE-4 Engine
Post by: pippin on 10/03/2016 09:44 PM
Well, NK-33 only had half the chamber pressure of Raptor so I'd say Raptors OR loop alone will probably be just as challenging as NK-33's from a materials perspective, especially considering that while the pressure differential and power output in the turbine might be comparable to NK-33 the actual pressure will still be twice as high.
Title: Re: Blue Origin's BE-4 Engine
Post by: Dante80 on 10/04/2016 12:08 PM
BO said it's doing a medium performance version of a high performance architecture. For reliability/reusability. SpaceX does a very high performance version of a very high performance architecture.

By the way, do we know why BO chose ORSC? It seems they want to avoid FRSC, which would preclude a FFSC architecture.

I think they went for it since it would be a better choice than FRSC, as far as the propellant mix is concerned. FRSC cycles are almost completely devoted to Hydrolox engines.
Title: Re: Blue Origin's BE-4 Engine
Post by: baldusi on 10/04/2016 02:19 PM
BO said it's doing a medium performance version of a high performance architecture. For reliability/reusability. SpaceX does a very high performance version of a very high performance architecture.

By the way, do we know why BO chose ORSC? It seems they want to avoid FRSC, which would preclude a FFSC architecture.

I think they went for it since it would be a better choice than FRSC, as far as the propellant mix is concerned. FRSC cycles are almost completely devoted to Hydrolox engines.
That is because with hydrolox you get something like 3 times more power to turbines by using FRSC than ORSC. On methalox, I think it was something like 30% more power by doing ORSC.
BTW, it is important to understand that instead of getting 30% more power you can decrease the delta-t by 30% and get cooler turbines. Both a big improvement for useful life and material reliability.
Title: Re: Blue Origin's BE-4 Engine
Post by: baldusi on 10/04/2016 02:34 PM
Well, NK-33 only had half the chamber pressure of Raptor so I'd say Raptors OR loop alone will probably be just as challenging as NK-33's from a materials perspective, especially considering that while the pressure differential and power output in the turbine might be comparable to NK-33 the actual pressure will still be twice as high.
NK-33 was a breakthrough for the West. But the first ORSC Russian rocket engine was OKB-1's S1.5400, which powered the Molnyia rocket third stage, and was operation by 1960.
And the RD-270 has a Pc of 26.4MPa, only surpassed by Raptor.
And the RD-253 had a T/W of 125 and the original design (which was actually supposed to be used on the N-1) was from 1960.
The "famous" T/W of the NK-33 is actually a lie. It was for a fixed engine with no TVC. If you calculated the T/W for RD-253 in that way, it would be 200. And when Aerojet added a TVC, it ended up with a T/W of 77.
In that sense, the best operative engine in the world, right now, is the RD-170 family and (you might argue) the Merlin 1D. But the RD-170 has been operative for more than 30 years.
Title: Re: Blue Origin's BE-4 Engine
Post by: Chris Bergin on 10/04/2016 08:09 PM
Thread is about BE-4. Please use this thread only for that engine (or it annoys people and they send report to mod alerts).
Title: Re: Blue Origin's BE-4 Engine
Post by: Oli on 10/05/2016 05:48 AM
BO said it's doing a medium performance version of a high performance architecture. For reliability/reusability. SpaceX does a very high performance version of a very high performance architecture.

By the way, do we know why BO chose ORSC? It seems they want to avoid FRSC, which would preclude a FFSC architecture.

Well, the decision is very easy from a thermodynamics POV. The power to your turbines is (basically) specific heat * mass flow. Do the numbers for methalox and you get more power with ORSC. They wanted a cheap engine, and so they went with a single turbine.
Nothing prevents them from then developing a full flow engine on that base. In fact, it would be "relatively" easy. The FRSC circuit is the easiest.

Thanks!

I found this explanation in a paper (http://www.rocket-propulsion.info/resources/articles/LPRE.pdf):

Quote
For  staged  combustion  cycles,  the  pressure  cascades
resulting  from  thrust  chamber  cooling  and  turbopump
power  requirements  are  compared  in  Figure  8  taking
LOX-methane  as  example.  The  pumping  requirements
are  lower  for  the  cycle  using  a  oxidizer-rich  preburner,
because no fuel is rerouted to the preburner after passing
through  the  thrust  chamber  cooling  channels.  The  small
amount of fuel required for the preburner is delivered by
a low-powered kick stage.

The    fuel-rich    cycle    results    in    higher    fuel-pump
requirements and requires an additional LOX-kick-stage,
while  the  ox.-rich  cycle  results  in  similar  lower  pump
requirements    without    a    kick-stage.    The    preburner
pressure is also lower in the ox.-rich cycle. However, the
oxygen-rich environment of the preburner gas may cause
additional complexity for the turbines as well as for hot-
gas lines and valves.

Is this what you meant?
Title: Re: Blue Origin's BE-4 Engine
Post by: baldusi on 10/05/2016 12:32 PM
Looking at it from another side, but yes. They are talking about the results.
Title: Re: Blue Origin's BE-4 Engine
Post by: TrevorMonty on 10/05/2016 01:46 PM
There is a fuel difference between BE4 and Raptor. BE4 is designed to use LNG while Raptor uses liquid methane (99% ?). How it affects engine design I'm not sure.

"Natural gas consists almost entirely of methane (CH4), the simplest hydrocarbon compound. Typically, LNG is 85 to 95-plus percent methane, along with a few percent ethane, even less propane and butane, and trace amounts of nitrogen"

With a large RLV fuel price starts to become significant part of operating costs. Blue have decided to use lower performing engine with cheaper fuel.
Title: Re: Blue Origin's BE-4 Engine
Post by: spacenut on 10/05/2016 02:10 PM
LNG and liquid methane are essentially the same thing.  During liquification, some impurites are drawn out.  LNG is about 95% methane.  At least it was with the company I worked for.  I've never heard of 85% unless it is at the well head and there it is separated out for 95% injected into transmission lines around the country. 

During chill down, some impurities like propane and butane can be separated out.  Propane liquifies at only about 10 lbs. leaving the methane.  Butane is similar.  Nitrogen will be heavier and settle to the bottom of methane in gas state.  Not that hard to separate during liquification of methane.  It might do it naturally during the process. 
Title: Re: Blue Origin's BE-4 Engine
Post by: Dante80 on 10/05/2016 02:49 PM
There is a fuel difference between BE4 and Raptor. BE4 is designed to use LNG while Raptor uses liquid methane (99% ?). How it affects engine design I'm not sure.

I might be wrong, but SpaceX may need neat methane due to their goal of chilling it more.
Title: Re: Blue Origin's BE-4 Engine
Post by: AncientU on 10/05/2016 04:36 PM
There is a fuel difference between BE4 and Raptor. BE4 is designed to use LNG while Raptor uses liquid methane (99% ?). How it affects engine design I'm not sure.

I might be wrong, but SpaceX may need neat methane due to their goal of chilling it more.

I've been assuming all along that they'll purify the LNG to avoid separation/icing from the heavier elements.
Title: Re: Blue Origin's BE-4 Engine
Post by: baldusi on 10/05/2016 05:55 PM
I think I remember Bezos stating that he said LNG to make things simple for the layman, but they were going to use liquid methane.
Title: Re: Blue Origin's BE-4 Engine
Post by: Nilof on 10/05/2016 07:07 PM
I think I remember Bezos stating that he said LNG to make things simple for the layman, but they were going to use liquid methane.

Didn't he state the exact opposite of that when asked at the ULA BE-4 for Vulcan announcement event? I may be misremembering things.


Either way, regarding the BE-4 vs Raptor comparisons, I think one thing worth mentioning regarding Blue's approach is that they have a lot of room for improving it much like SX did with the Merlin. If with these future upgrades they can double the chamber pressure to RD-180 levels, they'd suddenly have access to a ~5 MN engine, i.e. on par with the F-1. Given that the Merlin's thrust doubled between the first and latest versions, that shouldn't be impossible. It would allow New Glenn to grow in size to bigger-than-Saturn-V territory with future upgrades.
Title: Re: Blue Origin's BE-4 Engine
Post by: baldusi on 10/05/2016 09:22 PM
I would guess, that to have worse performance than RD-180, it should have about O/F 3.6, Pc 17MPa, ER 22, freezing at the 1.5 area ratio. With those parameters I get isp of 310s at SL and 335.75s in vacuum. In any case, to have worse isp than RD-180 BE-4 should have a relatively low Pc, for a staged engine.
The nice thing is that they can increase performance by increasing the Pc. The turbomachinery and certification is left as an exercise for the reader. :P
Title: Re: Blue Origin's BE-4 Engine
Post by: Dante80 on 10/06/2016 02:16 AM
On the other hand, I distinctly remember a couple of times (one if them in a congressional hearing too) where Blue has stated that "this is not exactly a methane engine but a liquefied natural gas engine".
Title: Re: Blue Origin's BE-4 Engine
Post by: Chasm on 10/12/2016 04:13 PM
Trying for LNG makes sense to me. Blue doesn't have the goal of ISRU on Mars at this time. If they can make the commercially available LNG work that should reduce propellant cost very nicely as compared to a highly refined version of the same.
LNG is not equal, every source has a different composition. As I understand the problems are less in the Methane content and more the impurities. (Water, N, CO2, H2S, ...) Maybe some additional refining is necessary.
So the question is, can they live with the limitations LNG imposes, and does it make sense on the financial side. Basically trading payload and engine lifetime for cheap and abundant propellant that should have no bottlenecks in the supply chain.
Title: Re: Blue Origin's BE-4 Engine
Post by: Stan-1967 on 10/12/2016 04:33 PM
I would guess, that to have worse performance than RD-180, it should have about O/F 3.6, Pc 17MPa, ER 22, freezing at the 1.5 area ratio. With those parameters I get isp of 310s at SL and 335.75s in vacuum. In any case, to have worse isp than RD-180 BE-4 should have a relatively low Pc, for a staged engine.
The nice thing is that they can increase performance by increasing the Pc. The turbomachinery and certification is left as an exercise for the reader. :P

What are the problems Blue Origin might encounter in scaling the BE-4 up to F1 class thrust?   I found it interesting that both Blue Origin and SpaceX ended up with similar class engines when designing around methane/LOX.  SpaceX certainly had initial hopes for a much higher thrust Raptor than what they are now promising.   IIRC SpaceX says Raptor is optimized for T/W, not total thrust.  SpaceX wanted a much higher thrust Raptor, but had to back off to the proposed 3050kN Raptor.


What are the inherent problems with methane that Blue Origin will bump against if they try to scale up BE-4?  Is it just turbomachinery?  Or are there deeper problems with combustion and flow that will rob performance from simply scaled up Pc?
Title: Re: Blue Origin's BE-4 Engine
Post by: TrevorMonty on 10/12/2016 08:26 PM
Why make larger BE4, just use more of them on NA. By time they fly on NA, the NG should have proved their reliability.
Title: Re: Blue Origin's BE-4 Engine
Post by: Prettz on 10/12/2016 08:44 PM
edit: nevermind, that was too off-topic.
Title: Re: Blue Origin's BE-4 Engine
Post by: Space Ghost 1962 on 10/13/2016 01:16 AM
Please note that we haven't yet seen a full scale engine firing on a BO test stand yet.

Making predictions about upping performance when it hasn't even fired ... is nuts.

At this point you're lucky if it doesn't explode on a start-up sequencing.
Title: Re: Blue Origin's BE-4 Engine
Post by: Nilof on 10/13/2016 03:33 AM
Blue has experience with developing rocket engines, and they have funding. All that talent that has been working on developing the BE-3 and BE-4 won't go away once the BE-4 is ready and certified. They'll be working on the next thing, whether it is an upgraded BE-4 or a next gen engine.
Title: Re: Blue Origin's BE-4 Engine
Post by: Space Ghost 1962 on 10/13/2016 04:14 AM
Wonderful but faith based assertions regardless of skill/accomplishments matters little at this point.

When the full scale components come together, all sorts of things suddenly matter that might not have been addressed before. You can end up losing months/years at this point very easily.

An expected "no brainer" turned out at this point to have a 2 year schedule slip, a hundred million overrun, and an even more costly follow-on. Experienced team, prime firm.
Title: Re: Blue Origin's BE-4 Engine
Post by: IainMcClatchie on 10/13/2016 05:04 AM
Let's not talk about faith but instead look at momentum.  Who is actually doing stuff?

What has the SpaceX engine team done in the last 7 years?
A: Draco, SuperDraco, Merlin 1C and 1D, Raptor.  Three different propellant combinations, three different architectures.  Two of the four have flown, maybe three if you count SuperDraco (abort test?)

What has the Blue Origin engine team done in the last 7 years?
A: BE-3 and BE-4 and it appears some kind of thruster.  Three different propellant combinations, three different architectures.  Two have flown.

What has the ULA engine team done in the last 7 years?
A: Spend more than SpaceX to validate that they could build a Russian engine if they had to.  Turned out they couldn't.

What has the ALR engine team done in the last 7 years?
A: Are these the folks working on the RS-25 mods for the SLS?

What has the ATK engine team done in the last 7 years?
A: 5 segment solid development from a 4 segment solid.

I'm pretty naive about the last three, so maybe I'm missing major developments.  But it appears SpaceX and Blue Origin have funded, capable teams actually testing new hardware.   The same doesn't appear to be true at the other three.  If I was a propulsion engineer passionate enough to rank what I'm doing over where I'm working or maybe existing benefits and seniority, where would I want to work?  I think it's the first two.  And that's the momentum.
Title: Re: Blue Origin's BE-4 Engine
Post by: TrevorMonty on 10/13/2016 08:29 AM
ULA don't do engine development inhouse they outsource it, no different from aircraft manufacturers. Has pluses once they have operational engine they don't have support an R&D team.

ALR are developing AR1, I doubt they will fail due to lack technical ability. Cancelled due to lack of funding or LV is more likely.
Title: Re: Blue Origin's BE-4 Engine
Post by: savuporo on 10/13/2016 09:02 AM
What has the ALR engine team done in the last 7 years?
A: Are these the folks working on the RS-25 mods for the SLS?
Uh, thats leaving out a ton of things. Like $1.2B J-2X engine
Title: Re: Blue Origin's BE-4 Engine
Post by: john smith 19 on 10/13/2016 09:34 AM
Wonderful but faith based assertions regardless of skill/accomplishments matters little at this point.

When the full scale components come together, all sorts of things suddenly matter that might not have been addressed before. You can end up losing months/years at this point very easily.

An expected "no brainer" turned out at this point to have a 2 year schedule slip, a hundred million overrun, and an even more costly follow-on. Experienced team, prime firm.
Indeed. IIRC during SSME development one RUD was traced to an angle sensor being mis-aligned to its shaft by 10 degrees.

However I'm sure all development team read "SSME:The First Ten Years" and are aware of this and the many other mishaps on the programme.

Staged combustion is very tricky and it's simpler to build a whole engine than each separate part and a set of very elaborate (IIRC one of the SSME part test rigs had 2000 fluid valves) rigs to test them.
Title: Re: Blue Origin's BE-4 Engine
Post by: Chasm on 10/13/2016 09:59 AM
More likely the AR1 gets developed to 90% flight readiness and then canceled like so many engines before it. Reference the ninety-ninety rule or a more fitting saying. :)


But back to the BE-4. It's hard to say what Blue Origin will do in the future, we don't even really know what they are doing now.
Lets try reading the tea leaves by looking at expectations. Blue and ULA must have had serious discussions about them.

ULA needs something right now, but they also need to keep that elusive perfect record for as long as possible. Performance? Enough is enough. Price point? Less than the other option ARJs AR1 would be welcome. Not very interested in experiments at this time.
Blue Origin needs something for their first orbital rocket. In this Millennium more engines means more margin and better reliability. Chances are that they want to iterate the design, a lot.

Neither of them needs the perfect engine, just one that is good enough for now. Preferably a design that has room for improvement so that they don't have to start from scratch after flying the first BE-4. Solving OSRC first certainly fits into the "Step by step ferociously" philosophy, as does starting with a lowish pressure version.

ULA repeatedly said that the engine down select comes at the end of the year or slightly later, after the BE-4 went on a test stand and has shown what it can('t) do. Taking the RS-68 lesson into account makes me think that it'll be the full scale engine that will have to meet or exceed the contracted requirements during the test campaign. Then there are another ~2 years until launch to show reliability.
We know that Blue used the BE-4 development to blow up various test articles before signing the ULA contract and a complete test stand one(?) year ago, so I suppose that they are beyond that stage by now.

Throwing all of the BE-4 development out that close to official testing because Raptor design goals have been released makes no sense. (As per the NSF article (https://www.nasaspaceflight.com/2016/10/its-propulsion-evolution-raptor-engine/) the tested Raptor was 1/3 power.)


I can see a future where BE-4 evolves into two production tracks. ULA buys the stable, proven version. The development version gets tested and then flies on New Glenn, once ULA sees enough improvements and is satisfied with the viability of the changes they switch their orders to the newer variant.
Blue has an incentive to keep evolving, but they also have an incentive to sell faultless engines.

As far as price goes, hard to tell. The only thing I remember reading is that Blue guaranteed a price set at 60% of what ARJ thought they could do the AR1 for. Did the grapevine really say that? If anywhere close to reality certainly an incentive.



For me the next major job for Blue after getting something to orbit, maybe even earlier, is to set up and communicate a development system. After all Blue had the opportunity to learn that while you do want to "fail early, fail often" there is also an enormous incentive isolate development anomalies from the operational launch business.

Four engine tracks:
Blue testing, on test stands
Blue development, experimental launch status
Blue stable, workhorse version on NG
Blue oldstable aka ULA version - perhaps also Blue HSF

(Yes, very much like Debian (https://wiki.debian.org/DebianReleases). If you start to introduce software development philosophies you might as well steal other stuff.)
Changes get introduced in testing and have to prove themself in each stage for at least x launches before advancing. If they fail, rinse and repeat.

I'd also try the same thing for New Glenn as a whole. Development, cargo & HSF tracks.
When a launch has been declared experimental and you book a flight on it for beer money there is a certain expectation that the payload may end up in the wrong orbit, or no orbit at all.
How to price that? The easy way out is of course Blue launching their own cargo, preferably have something that is cheap and easy to replace. If not, why not take a lesson from Amazon Web Services and just auction it of? Certainly cheaper than launching mass simulators.
(Just seeing the industry reaction to such an auction should be worth it.  8) )
Title: Re: Blue Origin's BE-4 Engine
Post by: TrevorMonty on 10/13/2016 01:20 PM
The BE4 may also be destined for Boeing/Blue XS1 booster. XS1 could be basis of reusable US for NG in future.
Title: Re: Blue Origin's BE-4 Engine
Post by: edkyle99 on 10/13/2016 02:53 PM
What has the ULA engine team done in the last 7 years?
A: Spend more than SpaceX to validate that they could build a Russian engine if they had to.  Turned out they couldn't.
ULA doesn't have an "engine team".  It is a launch vehicle integrator and launch service provider.  What it has been doing is performing more than 100 consecutive successful launches, even counting the AV-009 Centaur failure.
Quote
What has the ALR engine team done in the last 7 years?
A: Are these the folks working on the RS-25 mods for the SLS?
I'm not familiar with "ALR".  Aerojet Rocketdyne Holding's ticker symbol is AJRD.  Aerojet Rocketdyne has been working on RL10, AR-1, RS-25D testing for SLS, and closing out J-2X and AJ-26 among other things.
Quote
What has the ATK engine team done in the last 7 years?
A: 5 segment solid development from a 4 segment solid.
Also Castor 30, 30XL, and numerous defense missile motor contracts, among other things.

SpaceX is definitely the current leader in the U.S. for kerosene gas generator engines.  AJRD leads in LH2/LOX.  It remains to be seen who will be the winner in CH4/LOX, and even if CH4/LOX will beat RP/LOX for Vulcan, etc..

 - Ed Kyle
Title: Re: Blue Origin's BE-4 Engine
Post by: Jim on 10/13/2016 03:57 PM
.
What has the ULA engine team done in the last 7 years?
A: Spend more than SpaceX to validate that they could build a Russian engine if they had to.  Turned out they couldn't.


PW/AJR is responsible for building a US version of the RD-180.  And wrong, they could build it if wanted to.

.

What has the ALR engine team done in the last 7 years?
A: Are these the folks working on the RS-25 mods for the SLS?

AJR is the largest producer of thrusters.  They have developed many over the last decade. 
They also develop SRM's.

So, in summary, your take away was wrong
Title: Re: Blue Origin's BE-4 Engine
Post by: Ronsmytheiii on 10/13/2016 05:48 PM
Quote
Meyerson: “really great” progress on BE-4 engine; plan engine tests to begin early next year. #ISPCS2016

https://twitter.com/jeff_foust/status/786621077849907200
Title: Re: Blue Origin's BE-4 Engine
Post by: Dante80 on 10/13/2016 11:10 PM
I'm really looking forward to seeing this engine tested at full scale. It would be a very big and important milestone for Blue, and it could potentially shift a lot of things in the industry.

A 2,500 kN American ORSC engine! And with a new fuel type to boot! Who would have thought that we would get something like this that fast?
Title: Re: Blue Origin's BE-4 Engine
Post by: baldusi on 10/14/2016 04:00 PM
I'm really looking forward to seeing this engine tested at full scale. It would be a very big and important milestone for Blue, and it could potentially shift a lot of things in the industry.

A 2,500 kN American ORSC engine! And with a new fuel type to boot! Who would have thought that we would get something like this that fast?
Well, the methalox fuel has already been used on a test stand by Rocketdyne, Masten, Armadillo and SpaceX. So, it has even had operative missions. None orbital, of course.
But after a successful demonstration, it will really be an amazing achievement by Blue. But I want to stress that this is their fourth engine, with BE-2 and BE-3 having a pretty successful (if short) flight history. In fact, they have developed the very first operative tap-off engine, mastered the hydrolox propellant and now are embarked into the big boys club.
If you ask me, NPO Energomash, KBKhA, AerojetRocketdyne and SpaceX are ahead. But I would put them in the second slot with Snemca, MHI, Yuzhnoye, CASC 6th Academy and ISRO.
They are, right now, the rising star. And a successful program should put them right in equal footing with anybody else in the world. So, at least from my perspective, calling their work anything less than amazing progress, is selling them short.
Title: Re: Blue Origin's BE-4 Engine
Post by: Chasm on 10/29/2016 06:37 PM
In the wake of a fortune.com article Tory Bruno is commenting a bit about the current BE-4 and Vulcan status on /r/ula.

Quote from: Tory Bruno
However, BE4 remains our primary path and is doing very well, moving from near full scale into full scale testing as I type this. They have also been able to commit to a recurring price that meets our competitiveness needs.
Source (https://www.reddit.com/r/ula/comments/59io4t/the_great_rocket_race/d9cti4i/?context=3)

In another comment:
Quote from: Tory Bruno
Full scale firings is the big milestone. That likely happens early in 2017.
Source (https://www.reddit.com/r/ula/comments/59io4t/the_great_rocket_race/d9cuj3r/?context=3)


So things are looking good for the reveal of a full scale engine in the first quarter of 2017 or so. It also explains why ULA does not seem to be too concerned with the test delay.
Title: Re: Blue Origin's BE-4 Engine
Post by: Space Ghost 1962 on 10/29/2016 06:59 PM
Sounds nice. But leading up to full scale firing on test stand everyone must be concerned. Have to be. So critical.
Title: Re: Blue Origin's BE-4 Engine
Post by: Navier–Stokes on 11/18/2016 01:15 PM
New email update from Jeff Bezos:

Quote from: Jeff Bezos
For BE-4, not only do we have to design the engine itself, we also have to develop custom tools to make it. One of these tools is an automated electrical discharge machining (EDM) drilling machine. The EDM precisely locates and burns more than 4,000 tightly dimensioned holes into the nozzle and main combustion chamber, providing entry to the regenerative cooling channels.
 
As far as we know, this particular EDM machine is the only one of its kind in the world. It has 11 axes of motion allowing for precise hole location and accuracy within a few thousands of an inch. Its dual-head design results in reduced cycle time for the drilled holes. Brass multichannel electrodes are used to drill the holes. Water can be pumped through the electrode in order to speed up the drilling cycle. The use of water also helps flush the hole and remove the powder-like foreign object debris generated by the process. This eliminates the concern for plugging cooling channels, which can easily occur with conventional drilling methods. A pair of automated electrode-changing stations allows the EDM to continuously operate for long cycle times at an average rate of one hole every 90 seconds.
 
Building and operating custom tools of this magnitude is a big investment, but it’s critical for developing an engine that will power America’s access to space in the future.
 
A pretty wise investment, if you ask me.
 
Gradatim Ferociter!
 
Jeff Bezos
 
PS: Blue Origin is hiring. Check out our Careers (http://blueorigin.us9.list-manage.com/track/click?u=ca4c14684ac1af3f1219b4382&id=f3479d6d75&e=37b7bd39f5) page and apply.
Title: Re: Blue Origin's BE-4 Engine
Post by: TrevorMonty on 11/18/2016 02:35 PM
Selling these drilling machines could be little side business for Blue.
Title: Re: Blue Origin's BE-4 Engine
Post by: acsawdey on 11/18/2016 02:49 PM
So -- 4000 holes * 90 seconds = 100 hours on this machine to drill the holes for one engine? I suppose that doesn't matter too much if your intention is to reuse things so you don't have to build that many.
Title: Re: Blue Origin's BE-4 Engine
Post by: notsorandom on 11/18/2016 04:51 PM
So -- 4000 holes * 90 seconds = 100 hours on this machine to drill the holes for one engine? I suppose that doesn't matter too much if your intention is to reuse things so you don't have to build that many.
The nice thing about these machines is that they don't go home after an eight hour shift. Its a little under four days of constant work. Assuming that there was about 50% downtime one of these machines could do about an engine a week. If this was the bottle neck of production Blue could still make at least 40 a year. I wonder how long it would take to do this the old way with a machine shop.
Title: Re: Blue Origin's BE-4 Engine
Post by: baldusi on 11/18/2016 05:38 PM
So -- 4000 holes * 90 seconds = 100 hours on this machine to drill the holes for one engine? I suppose that doesn't matter too much if your intention is to reuse things so you don't have to build that many.
RS-68 has a lead time of 36 months. I think that the ablative MCC/nozzle takes something like 6 months to do. 100hr for an injector plate is really fast.
Title: Re: Blue Origin's BE-4 Engine
Post by: russianhalo117 on 11/18/2016 05:54 PM
So -- 4000 holes * 90 seconds = 100 hours on this machine to drill the holes for one engine? I suppose that doesn't matter too much if your intention is to reuse things so you don't have to build that many.
RS-68 has a lead time of 36 months. I think that the ablative MCC/nozzle takes something like 6 months to do. 100hr for an injector plate is really fast.
RS-68A is slightly less than 36 months now due to improvements and lessons learned being applied to its manufacturing process.

Theoretically you could install more EDM arms to speed the process up, but the current setup is fine for testing and initial production rate.
Title: Re: Blue Origin's BE-4 Engine
Post by: Prober on 11/22/2016 03:59 PM
So -- 4000 holes * 90 seconds = 100 hours on this machine to drill the holes for one engine? I suppose that doesn't matter too much if your intention is to reuse things so you don't have to build that many.
RS-68 has a lead time of 36 months. I think that the ablative MCC/nozzle takes something like 6 months to do. 100hr for an injector plate is really fast.
RS-68A is slightly less than 36 months now due to improvements and lessons learned being applied to its manufacturing process.

Theoretically you could install more EDM arms to speed the process up, but the current setup is fine for testing and initial production rate.


Where's the complexity on the RS-68A thought that was designed to be cheap?

Title: Re: Blue Origin's BE-4 Engine
Post by: Space Ghost 1962 on 11/22/2016 06:07 PM
Where's the complexity on the RS-68A thought that was designed to be cheap?
Compared to SSME it was derived from, any rocket engine short of the F1 is designed to be cheaper ...  ::)
Title: Re: Blue Origin's BE-4 Engine
Post by: baldusi on 11/22/2016 06:19 PM
Where's the complexity on the RS-68A thought that was designed to be cheap?
Compared to SSME it was derived from, any rocket engine short of the F1 is designed to be cheaper ...  ::)
I think that they used an ablative main combustion chamber and nozzle to "cut costs", and made a very simple gas generator. They also re-used as much of the SSME tooling as possible. Supposedly they would build 30 or more engines per year and thus it would be "dirty cheap".
Then the project had lower performance than expected, DIV was found to have cheated and thus its orders slashed and SSME production was ended. Perfect storm that made it very expensive.
If you look at Merlin's history, you will see that at the time (late 90s early 2000s) it was thought that ablative MCC and nozzle were a great cost trade off. Apparently the reality has been different. Ditto with hydrogen/LOX. I think that too many decades of Rocketdyne/NASA making all decisions made them think that their way of doing things was the only way. Then came NPO Energomash to the international market and you know how it ended.
Title: Re: Blue Origin's BE-4 Engine
Post by: Space Ghost 1962 on 11/22/2016 07:08 PM
First a reminder that this is the BE-4 thread and your posts should reflect that.  8)

Where's the complexity on the RS-68A thought that was designed to be cheap?
Compared to SSME it was derived from, any rocket engine short of the F1 is designed to be cheaper ...  ::)
I think that they used an ablative main combustion chamber and nozzle to "cut costs", and made a very simple gas generator.

These were done for speed and not so much for cost. Also, the benefits for a booster engine in translating mass flows into thrust for hydrolox. Otherwise you'd have a significant wait to make the staged combustion work for STBE like application better.

BE-4 does ORSC for a booster engine (with the potential for a US application not unlike J-2X/MVac large nozzle), where combustion efficiency of minimal mass flow is desired. Speed to completion more by tools/simulation/small scale prototypes etc that RS-68 couldn't take the time for as a respin of SSME.

Quote
They also re-used as much of the SSME tooling as possible. Supposedly they would build 30 or more engines per year and thus it would be "dirty cheap".
For speed to completion as the first commercial engine.

The "dirt cheap" was in sharing components and piggybacking all the work for the logistical "wedge" of the SSME and the Shuttle base - it artificially increased the number of engines to make both programs cheaper as long as Shuttle flew, and it was way oversold.

You can't take an expensive logistical structure and expect LRE's alone to make an industry out of it, that will then make it cheap. Best you can do is make it less expensive, if you have enough volume (that was the point).

The "cheap" of BE-4 likely will be in the manner of production, the business model, and the cost sharing with ULA. like first stage reuse economics remain to be seen.

Quote
Then the project had lower performance than expected, DIV was found to have cheated and thus its orders slashed and SSME production was ended. Perfect storm that made it very expensive.
Because everything was in the margins, the rush to win the deal that wasn't, and there was no "Block 2" redux to recapture. All or nothing then something but not enough to matter.

Which is why I am critical of the Raptor/BE4/AR1 "new big engine". Billionaires/lobbyists can temporarily suspend the "laws of economics", but sooner or later they reassert.

Quote
If you look at Merlin's history, you will see that at the time (late 90s early 2000s) it was thought that ablative MCC and nozzle were a great cost trade off. Apparently the reality has been different. Ditto with hydrogen/LOX.
Think of this differently. Too tiny a sample set with too much riding off of it for the speculative examples to resolve in time to tell.

So need drives design thrash, and broad industry (kerosene/methane/regenerative) drives scalable propulsion success. If Henry Ford had successfully built hydrogen powered cars (impossible),  perhaps a different future.

As for ablative nozzles, they are a "cusp" technology ... still. You might be able to make them work, but in the same sense that Jim makes for subcooled LOX with F9, it may be of marginal advantage for indeterminate risk.

Quote
I think that too many decades of Rocketdyne/NASA making all decisions made them think that their way of doing things was the only way. Then came NPO Energomash to the international market and you know how it ended.
Both are examples of different kinds of pragmatism/politics.

Why "commercial" worked better for Merlin than RS68 was the thumb on the scales.

Watching BE4 closely for thumbs on the scales like AR1 already has. Raptor has no thumb on the scale.

add: missed some things.
Title: Re: Blue Origin's BE-4 Engine
Post by: TrevorMonty on 11/22/2016 07:35 PM
The BE4 production rate should be >30 a year. 10-20 for ULA (5-10 x Vulcan). 1 per NG flight for expendable US. 7 x NG Booster, even though it is reusable they will need to build a small fleet of boosters plus replace engines after so many flights.

By time Vulcan is reusing BE4 in 2023-25, NG should have high flight rate assuming Blues vision for HSF pans out.
Title: Re: Blue Origin's BE-4 Engine
Post by: baldusi on 11/22/2016 08:02 PM
The BE4 production rate should be >30 a year. 10-20 for ULA (5-10 x Vulcan). 1 per NG flight for expendable US. 7 x NG Booster, even though it is reusable they will need to build a small fleet of boosters plus replace engines after so many flights.

By time Vulcan is reusing BE4 in 2023-25, NG should have high flight rate assuming Blues vision for HSF pans out.
BE-4 has some important advantages in cost wrt the RS-68A.
One is that since SLI in the 1990s, the US has gone through a lot of engine development efforts through many companies. While some don't even exist anymore, many of the Blue engineers have worked previously on many engine projects and they have a huge stack of lessons learned.
The other is that a lot of companies have proven that engines can be done relatively cheap. Blue can just leverage the best practices and then innovate on cost.
But more importantly, is that Blue has a very knowledgeable leader that let's engineers make the best technical choice since he is not married to any supplier. It is not surprising that KBKhA, NPO Energomash, SpaceX and Blue Origin went with CH4/LOX when they had to do a highly reusable engine. Rocketdyne/Aerojet have always proposed hydrolox, because that was NASA's heritage.
The last is the financing source. They have an extremely predictable cashflow and only care about long term cost. No worries about keeping the program, maintaining the appropriations or keeping big contracts.
Title: Re: Blue Origin's BE-4 Engine
Post by: RedLineTrain on 11/22/2016 08:11 PM
Why "commercial" worked better for Merlin than RS68 was the thumb on the scales.

Watching BE4 closely for thumbs on the scales like AR1 already has. Raptor has no thumb on the scale.

Can you please talk a little about what you mean by "thumb on the scale"?  Government development money?  Ill-advised government requirements?

Thanks.
Title: Re: Blue Origin's BE-4 Engine
Post by: Space Ghost 1962 on 11/22/2016 08:32 PM
BE-4 has some important advantages in cost wrt the RS-68A.
Nope. SSME giveth/taketh. RS68 "could'a should'a would'a" been a follow-on to SSME with better performance/cost ... but there wasn't budget/time for that. The point was to win EELV program, then gradually redress all else.

Quote
One is that since SLI in the 1990s, the US has gone through a lot of engine development efforts through many companies. While some don't even exist anymore, many of the Blue engineers have worked previously on many engine projects and they have a huge stack of lessons learned.
The other is that a lot of companies have proven that engines can be done relatively cheap. Blue can just leverage the best practices and then innovate on cost.
Like Aerojet Rocketdyne has also done. We'll see.

Quote
But more importantly, is that Blue has a very knowledgeable leader that let's engineers make the best technical choice since he is not married to any supplier.
On that I can agree for SX/BO.


Quote
It is not surprising that KBKhA, NPO Energomash, SpaceX and Blue Origin went with CH4/LOX when they had to do a highly reusable engine. Rocketdyne/Aerojet have always proposed hydrolox, because that was NASA's heritage.
Hydrolox also fits desired political aerospace model, where launch costs are never intended to get cheap.

Quote
The last is the financing source. They have an extremely predictable cashflow and only care about long term cost. No worries about keeping the program, maintaining the appropriations or keeping big contracts.
Yes but. When you scale a program to BE4/NG levels, your program risk footprint has a power function increase i.e. not linear as cash flow. So either you cost leverage (ULA), or increase funding, or slow down.

Can you please talk a little about what you mean by "thumb on the scale"?
For RS68 it was to please the Shuttle industrial base at the long term cost to the program.

SX has none of this because since they fully absorb the cost of engines, there isn't anyone along the "food chain" to feed.

Is the same true for BO? It should be. However, they cut deals, like with ULA and others. They clearly don't fully absorb the costs of engines. What if there are more deals with terms significant enough to matter?

In the case of AR1, to get those fine government contracts you bet they have a lot of outside mouths to feed.
Title: Re: Blue Origin's BE-4 Engine
Post by: Navier–Stokes on 01/19/2017 04:43 PM
Quote from: Underappreciated Engine Components - The Ox Boost Pump
Robert Goddard’s first rockets used compressed gas to force the liquid propellants into the engine thrust chambers. While simple in design and a logical starting point, he quickly realized the limitations with this approach: it requires thick-walled heavy propellant tanks and limits the engine’s chamber pressure and performance, both of which limit payload capacity. The answer was turbopumps. Store the propellants in low-pressure light tanks, and then pump the propellants up to high pressure just ahead of injection into the main chamber.

For even more performance, you can add one or more boost pumps ahead of the main pumps. We’ve done that on the oxidizer side of our BE-4 engine. Our Ox Boost Pump (OBP) design leverages 3-D additive manufacturing to make many of the key components. The housing is a single printed aluminum part and all of the stages of the hydraulic turbine are printed from Monel, a nickel alloy. This manufacturing approach allows the integration of complex internal flow passages in the housing that would be much more difficult to make using conventional methods. The turbine nozzles and rotors are also 3-D printed and require minimum machining to achieve the required fits.

The OBP was first demonstrated last year in testing, where we validated its interaction with a main pump. The second iteration of the OBP for BE-4 is now in test. We’ve also just finished assembly of the unit that we’ll install for the first all-up BE-4 engine test.

We’ll keep you posted on how our BE-4 powerpack and engine testing progresses.

Gradatim Ferociter!

Jeff Bezos
Title: Re: Blue Origin's BE-4 Engine
Post by: Space Ghost 1962 on 01/19/2017 11:36 PM
Note the discrete mention of powerpack testing apart from engine testing.

Many times development doesn't get further than the powerpack. Many examples.

With LNG, combustion stability is a definite issue post powerpack. And you can get past powerpack test w/o dealing with ORSC materials issues. However ...

So this one is a touchy one to evaluate just where they are in the development cycle. For ULA to sign-off on BE-4 as primary engine source, one might expect a fair portion of a full burn of a prototype full-scale engine.

Powerpack test to that in less than 6 months would be quite an accomplishment.
Title: Re: Blue Origin's BE-4 Engine
Post by: meberbs on 01/20/2017 12:31 AM
Powerpack test to that in less than 6 months would be quite an accomplishment.
Powerpack  testing for BE-4 goes back to fall 2014 (see here. (http://spacenews.com/blue-origin-completes-be-3-engine-as-be-4-work-continues/))

The current testing seems like it is just a final validation, or for determining some control parameters, since they stated they have already built some of the hardware for the full up test.
Title: Re: Blue Origin's BE-4 Engine
Post by: Space Ghost 1962 on 01/20/2017 01:52 AM
Powerpack test to that in less than 6 months would be quite an accomplishment.
Powerpack  testing for BE-4 goes back to fall 2014 (see here. (http://spacenews.com/blue-origin-completes-be-3-engine-as-be-4-work-continues/))

The current testing seems like it is just a final validation, or for determining some control parameters, since they stated they have already built some of the hardware for the full up test.

Source please? I don't read it that way at all. Not to be a jerk, but need better than "seems like".

You prove the powerpack for output and reliability. Then you incorporate into the engine sans nozzle and work on startup sequencing, hopefully w/o building an immense fragmentation grenade ...
Title: Re: Blue Origin's BE-4 Engine
Post by: Star One on 01/20/2017 04:17 PM
Powerpack test to that in less than 6 months would be quite an accomplishment.
Powerpack  testing for BE-4 goes back to fall 2014 (see here. (http://spacenews.com/blue-origin-completes-be-3-engine-as-be-4-work-continues/))

The current testing seems like it is just a final validation, or for determining some control parameters, since they stated they have already built some of the hardware for the full up test.

Source please? I don't read it that way at all. Not to be a jerk, but need better than "seems like".

You prove the powerpack for output and reliability. Then you incorporate into the engine sans nozzle and work on startup sequencing, hopefully w/o building an immense fragmentation grenade ...

You say not to be a jerk, because to me that looks an entirely reasonable link having read it for the point they were making. Also you know very well that to get a cast iron source on something like that with BO's legendary secrecy is going to be pretty difficult so it makes you appear pedantic even if you didn't mean to come across that way.
Title: Re: Blue Origin's BE-4 Engine
Post by: baldusi on 01/20/2017 05:31 PM
Powerpack test to that in less than 6 months would be quite an accomplishment.
Powerpack  testing for BE-4 goes back to fall 2014 (see here. (http://spacenews.com/blue-origin-completes-be-3-engine-as-be-4-work-continues/))

The current testing seems like it is just a final validation, or for determining some control parameters, since they stated they have already built some of the hardware for the full up test.

Source please? I don't read it that way at all. Not to be a jerk, but need better than "seems like".

You prove the powerpack for output and reliability. Then you incorporate into the engine sans nozzle and work on startup sequencing, hopefully w/o building an immense fragmentation grenade ...

From the email:

Quote
The OBP was first demonstrated last year in testing, where we validated its interaction with a main pump. The second iteration of the OBP for BE-4 is now in test. We’ve also just finished assembly of the unit that we’ll install for the first all-up BE-4 engine test.

They are assembling the final engine for the first integrated test. That's the last step before actual hot firing. You don't do assembly until you have validated and certified each individual subsystem.
Title: Re: Blue Origin's BE-4 Engine
Post by: Space Ghost 1962 on 01/21/2017 02:00 AM
Powerpack test to that in less than 6 months would be quite an accomplishment.
Powerpack  testing for BE-4 goes back to fall 2014 (see here. (http://spacenews.com/blue-origin-completes-be-3-engine-as-be-4-work-continues/))

The current testing seems like it is just a final validation, or for determining some control parameters, since they stated they have already built some of the hardware for the full up test.

Source please? I don't read it that way at all. Not to be a jerk, but need better than "seems like".

You prove the powerpack for output and reliability. Then you incorporate into the engine sans nozzle and work on startup sequencing, hopefully w/o building an immense fragmentation grenade ...

From the email:

Quote
The OBP was first demonstrated last year in testing, where we validated its interaction with a main pump. The second iteration of the OBP for BE-4 is now in test. We’ve also just finished assembly of the unit that we’ll install for the first all-up BE-4 engine test.

They are assembling the final engine for the first integrated test.
We are in agreement. I called it "incorporated". My issue is the "powerpack test" callout.

Quote
That's the last step before actual hot firing.
With closed cycle engines, there's a limit to separable component testing.

Quote
You don't do assembly until you have validated and certified each individual subsystem.

But you can't deal with materials/erosion issues, a key issue with ORSC, until much of the engine is operating as a complete unit.

So my issue was in reference to if the powerpack was finished in development, given the powerpack test reference.

Now I understand the desire for advocates/fans to not have certain things questioned, that set off such hurt feelings. But the confusion here is a polite and valid one.
Title: Re: Blue Origin's BE-4 Engine
Post by: meberbs on 01/21/2017 07:28 AM
But you can't deal with materials/erosion issues, a key issue with ORSC, until much of the engine is operating as a complete unit.

So my issue was in reference to if the powerpack was finished in development, given the powerpack test reference.

Now I understand the desire for advocates/fans to not have certain things questioned, that set off such hurt feelings. But the confusion here is a polite and valid one.
My original statement (the one where I used "seems like" to emphasize that it was just my interpretation of the available information) was intended to suggest that the currently ongoing testing is likely the last or nearly last of the testing of components or sub-assemblies before they move on to testing of a full engine. This is just based on the fact that they have been running tests for over 2 years, so combined with statements of having built hardware that will go in the full engine, it will not be surprising if they have an engine on a stand within 6 months.

I can understand how some of what I said may have been interpreted differently, and I agree that there are definitely risks and challenges with the full engine that can't be proven to work from component tests. There is a reason ULA is waiting to see the full engine run before they officially downselect for Vulcan.
Title: Re: Blue Origin's BE-4 Engine
Post by: FutureSpaceTourist on 01/28/2017 09:23 PM
Interesting series of tweets on BE-4 development:

Quote
Blue Origin BE-4 Powerpack installed on test stand in West Texas for 'start transient' testing (2015) #RoadToHotfire #BE4
https://twitter.com/megsylhydrazine/status/825461150028476416 (https://twitter.com/megsylhydrazine/status/825461150028476416)

Quote
Blue Origin BE-4 Powerpack in operation during start transient testing (2015) 🚀 #RoadToHotfire #BE4
https://twitter.com/megsylhydrazine/status/825462058191708160 (https://twitter.com/megsylhydrazine/status/825462058191708160)

Quote
Subscale BE-4 in a highly-instrumented calorimeter tested the preburner & regeneratively cooled chamber + nozzle (2016) 🚀#RoadToHotfire #BE4
https://twitter.com/megsylhydrazine/status/825465331837607936 (https://twitter.com/megsylhydrazine/status/825465331837607936)

Quote
BE-4 Preburner Injector #CFD model shows temperature distribution of hot gaseous oxygen entering the turbine #RoadToHotfire #BE4
https://twitter.com/megsylhydrazine/status/825466390534447104 (https://twitter.com/megsylhydrazine/status/825466390534447104)

Quote
BE-4 staged-combustion tests confirmed pretest predictions of injector performance, heat transfer & combustion stability #RoadToHotfire #BE4
https://twitter.com/megsylhydrazine/status/825468103534317568 (https://twitter.com/megsylhydrazine/status/825468103534317568)
Title: Re: Blue Origin's BE-4 Engine
Post by: FutureSpaceTourist on 01/28/2017 09:33 PM
There's a short video attached to this tweet don't know how to embed:

Quote
Subscale BE-4 making smoke & fire in Texas! More than 3 years into development, #BE4 will be qualified for flight this year #RoadToHotfire

https://twitter.com/megsylhydrazine/status/825471035831046145 (https://twitter.com/megsylhydrazine/status/825471035831046145)

Edit: video link https://twitter.com/Megsylhydrazine/status/825471035831046145/video/1‬ (https://twitter.com/Megsylhydrazine/status/825471035831046145/video/1‬)
Title: Re: Blue Origin's BE-4 Engine
Post by: FutureSpaceTourist on 01/28/2017 09:41 PM
Quote
New test cell for BE-4 pressure-fed preburner testing to support dev. of start & ignition sequence timing for powerpack #RoadToHotfire #BE4

https://twitter.com/megsylhydrazine/status/825473262536663040 (https://twitter.com/megsylhydrazine/status/825473262536663040)
Title: Re: Blue Origin's BE-4 Engine
Post by: FutureSpaceTourist on 01/28/2017 09:47 PM
Quote
BE-4 pressure-fed preburner (14") testing in the new test cell🚀 These tests are developing the transient start sequence #RoadToHotfire #BE4

https://twitter.com/megsylhydrazine/status/825474421255081984 (https://twitter.com/megsylhydrazine/status/825474421255081984)
Title: Re: Blue Origin's BE-4 Engine
Post by: Space Ghost 1962 on 01/29/2017 02:15 AM
This is the best information on BE-4 publicly released. And they seem to be making excellent progress.

Particularly like the CFD model and the wear before/after photos. It's about what you'd like to see leading up to a full scale on test stand.

At a guess it looks like they are within 3 months of a burp test of a full scale closed cycle engine.

Note the subscale engine firing and the test stand with its essential protection.

Congrats to the Blue Origin engine team, and to Blue Origin for the thorough communication in pictures of engine development status.

And ... You've "one upped" on SX in being more communicative than they are about Raptor.

Good luck on making that full scale engine fire an effective reality.
Title: Re: Blue Origin's BE-4 Engine
Post by: old_sellsword on 01/29/2017 02:22 AM
and to Blue Origin for the thorough communication in pictures of engine development status.

And ... You've "one upped" on SX in being more communicative than they are about Raptor.

I'm just wondering why this information came through employees' personal Twitter and YouTube accounts, instead of official communication channels.
Title: Re: Blue Origin's BE-4 Engine
Post by: Lar on 01/29/2017 03:15 AM
and to Blue Origin for the thorough communication in pictures of engine development status.

And ... You've "one upped" on SX in being more communicative than they are about Raptor.

I'm just wondering why this information came through employees' personal Twitter and YouTube accounts, instead of official communication channels.

Hopefully it doesn't get that employee fired...
Title: Re: Blue Origin's BE-4 Engine
Post by: gongora on 01/29/2017 03:34 AM
and to Blue Origin for the thorough communication in pictures of engine development status.

And ... You've "one upped" on SX in being more communicative than they are about Raptor.

I'm just wondering why this information came through employees' personal Twitter and YouTube accounts, instead of official communication channels.

Hopefully it doesn't get that employee fired...

Is it an employee?  Her twitter feed has stuff about lots of different rocket companies.
Title: Re: Blue Origin's BE-4 Engine
Post by: old_sellsword on 01/29/2017 03:35 AM
and to Blue Origin for the thorough communication in pictures of engine development status.

And ... You've "one upped" on SX in being more communicative than they are about Raptor.

I'm just wondering why this information came through employees' personal Twitter and YouTube accounts, instead of official communication channels.

Hopefully it doesn't get that employee fired...

Is it an employee?  Her twitter feed has stuff about lots of different rocket companies.

Her description says "Seattle, Washington" and she has a picture with the New Shepard booster and capsule.

Edit: Although I'm now realizing all the pictures she tweeted were already publicly released, and that video is just a compilation of other released media. Is all this stuff anything we haven't seen before?
Title: Re: Blue Origin's BE-4 Engine
Post by: Craftyatom on 01/29/2017 05:03 AM
Quote
BE-4 Preburner Injector #CFD model shows temperature distribution of hot gaseous oxygen entering the turbine #RoadToHotfire #BE4
https://twitter.com/megsylhydrazine/status/825466390534447104 (https://twitter.com/megsylhydrazine/status/825466390534447104)

Is that model in... degrees Rankine?

I thought NASA was the only entity stubborn enough to still be adhering to that bloody measurement system...
Title: Re: Blue Origin's BE-4 Engine
Post by: meberbs on 01/29/2017 11:39 AM
Quote
BE-4 Preburner Injector #CFD model shows temperature distribution of hot gaseous oxygen entering the turbine #RoadToHotfire #BE4
https://twitter.com/megsylhydrazine/status/825466390534447104 (https://twitter.com/megsylhydrazine/status/825466390534447104)

Is that model in... degrees Rankine?

I thought NASA was the only entity stubborn enough to still be adhering to that bloody measurement system...
U.S. engineering is stuck with stupid units in many areas, because that is what all of the reference tables use. (If NASA uses it, and they are provide a historical database you want to compare against....)

My propulsion class largely used "English" units instead of metric, but the book didn't even use consistent units: it used pounds mass instead of slugs, so "g" would show up all over the place even though gravity wasn't involved in the equations.
Title: Re: Blue Origin's BE-4 Engine
Post by: ethan829 on 01/29/2017 03:53 PM
and to Blue Origin for the thorough communication in pictures of engine development status.

And ... You've "one upped" on SX in being more communicative than they are about Raptor.

I'm just wondering why this information came through employees' personal Twitter and YouTube accounts, instead of official communication channels.


All of this has been previously released by Blue Origin through official channels (primarily their mailing list). You can sign up here: https://www.blueorigin.com/interested
Title: Re: Blue Origin's BE-4 Engine
Post by: ZachF on 01/30/2017 01:39 AM
Methalox engines sure do make some pretty flames.
Title: Re: Blue Origin's BE-4 Engine
Post by: woods170 on 01/30/2017 06:54 AM
And ... You've "one upped" on SX in being more communicative than they are about Raptor.
I hear Ed talking  ;)
Title: Re: Blue Origin's BE-4 Engine
Post by: Space Ghost 1962 on 01/31/2017 04:53 AM
And ... You've "one upped" on SX in being more communicative than they are about Raptor.
I hear Ed talking  ;)
Nah - he's mad at me. As usual.
Title: Re: Blue Origin's BE-4 Engine
Post by: Nomic on 01/31/2017 09:59 AM
Cant remember seeing the pictures of the turbopumps before, reverse image shows they have been around since September 2015 for the frosted image (picture of the whole test stand (http://www.americaspace.com/?p=86272)), February last year for the un-frosted.

Might be reading to much into it, but those pictures looks more like the design form the original announcement with ULA, turbopump along the top, rather than down the side. Wonder if there has been a redesign somewhere along the way, though it would be more surprising if they didn't have to make some significant changes along the way.
Title: Re: Blue Origin's BE-4 Engine
Post by: FutureSpaceTourist on 03/06/2017 01:11 PM
Ninja'd in updates thread:

@JeffBezos  15m15 minutes ago

 1st BE-4 engine fully assembled. 2nd and 3rd following close behind. #GradatimFerociter

@JeffBezos  11m11 minutes ago

 Here’s one more shot of BE-4 in its transport cradle.

Edit: for the record here are the links

https://twitter.com/jeffbezos/status/838748139964272640 (https://twitter.com/jeffbezos/status/838748139964272640)
https://twitter.com/jeffbezos/status/838748973598900225 (https://twitter.com/jeffbezos/status/838748973598900225)
Title: Re: Blue Origin's BE-4 Engine
Post by: FutureSpaceTourist on 03/06/2017 01:27 PM
In response to Jeff Bezos' tweets:

Quote
Good looking engine. Looking forward to seeing its hot fire performance
https://twitter.com/torybruno/status/838751831262113793 (https://twitter.com/torybruno/status/838751831262113793)

Quote
@torybruno Do you know when this is planned?
https://twitter.com/tobiasvdb/status/838752089597755392 (https://twitter.com/tobiasvdb/status/838752089597755392)

Quote
@TobiasVdb very soon
https://twitter.com/torybruno/status/838754433668362240 (https://twitter.com/torybruno/status/838754433668362240)

Quote
BE4 is the primary path to replace the Atlas' Russian RD180. Looking good
https://twitter.com/torybruno/status/838755076449701892 (https://twitter.com/torybruno/status/838755076449701892)
Title: Re: Blue Origin's BE-4 Engine
Post by: AncientU on 03/06/2017 07:38 PM
In response to Jeff Bezos' tweets:

...

Quote
BE4 is the primary path to replace the Atlas' Russian RD180. Looking good
https://twitter.com/torybruno/status/838755076449701892 (https://twitter.com/torybruno/status/838755076449701892)

Primary path... doesn't sound too good for the AR-1.
Title: Re: Blue Origin's BE-4 Engine
Post by: ugordan on 03/06/2017 07:40 PM
doesn't sound too good for the AR-1.

It never did.
Title: Re: Blue Origin's BE-4 Engine
Post by: edkyle99 on 03/06/2017 08:30 PM
In response to Jeff Bezos' tweets:

...

Quote
BE4 is the primary path to replace the Atlas' Russian RD180. Looking good
https://twitter.com/torybruno/status/838755076449701892 (https://twitter.com/torybruno/status/838755076449701892)

Primary path... doesn't sound too good for the AR-1.
BE-4 was always the preferred choice for Vulcan, but the real decision will be made by the hardware when they fire these things up.  Staged combustion development testing has historically resulted in hair-pulling frustration. 

 - Ed Kyle
Title: Re: Blue Origin's BE-4 Engine
Post by: yokem55 on 03/06/2017 08:34 PM
The engine looks physically quite large compared to the notional size of the full powered Raptor. Quite curious about what this guy's TWR is...
Title: Re: Blue Origin's BE-4 Engine
Post by: HVM on 03/06/2017 09:19 PM
Coz RD-180 is same size and have similar thrust as BE-4. It's the Raptor which is odd one here.
Title: Re: Blue Origin's BE-4 Engine
Post by: Space Ghost 1962 on 03/06/2017 09:32 PM
In response to Jeff Bezos' tweets:

...

Quote
BE4 is the primary path to replace the Atlas' Russian RD180. Looking good
https://twitter.com/torybruno/status/838755076449701892 (https://twitter.com/torybruno/status/838755076449701892)

Primary path... doesn't sound too good for the AR-1.

BE-4 was always the preferred choice for Vulcan, but the real decision will be made by the hardware when they fire these things up.

Methalox appears to be more compatible with simulations than kerolox and hydrolox ever were.

Looking very likely that the race to second successful large scale firing will be won by BE-4 after Raptor. By all accounts, AR-1 is still a year plus behind full scale. Not sure if they even have a test stand for it.

And this one is full scale, unlike Raptor's slightly subscale.

Quote
Staged combustion development testing has historically resulted in hair-pulling frustration. 

Three examples here Ed. I'll bet that the last one will take the longest to make it though start up sequencing.

You'll note that we are quite aways away from a full power, full duration burn on any of them.

add:
Oh and congratulations to Blue Origin on the fine engine - it will look even better on your test stand, in operation, which I earnestly hope will go well. Looking forward to your welcome to the methalox propulsion club.

Bet a cup of coffee that they'll have a half minute plus burn before June. Anyone want to bet against that?
Title: Re: Blue Origin's BE-4 Engine
Post by: Davidthefat on 03/07/2017 07:11 AM
Bet a cup of coffee that they'll have a half minute plus burn before June. Anyone want to bet against that?

I'll bet you on that.
Title: Re: Blue Origin's BE-4 Engine
Post by: WindnWar on 03/07/2017 01:16 PM
The engine looks physically quite large compared to the notional size of the full powered Raptor. Quite curious about what this guy's TWR is...

The specs for the chamber pressure is only about 30% higher than a gas generator engine like Merlin or RS-68A, so if anything it will likely have a worse thrust to weight ratio than RD-180 has of 77 to 1. Can't know for sure till the specs are released though. On the other hand if the specs are based on a very conservative initial version, they probably have room to raise its performance over time.

Too much guessing at this stage though.
Title: Re: Blue Origin's BE-4 Engine
Post by: GWH on 03/07/2017 01:24 PM
Does the nozzle on the vac variant seem small to anyone else?

EDIT: Screen grab and very basic scaling of the video.  Referencing 7m stage diameter gives approx 3.2m diameter nozzle.  Shot in the dark guess on the 1st stage variant posted is that it's at least 2m?
Title: Re: Blue Origin's BE-4 Engine
Post by: PahTo on 03/07/2017 02:13 PM
Does the nozzle on the vac variant seem small to anyone else?

BE-4 is a booster engine.
Title: Re: Blue Origin's BE-4 Engine
Post by: Navier–Stokes on 03/07/2017 02:24 PM
Does the nozzle on the vac variant seem small to anyone else?

BE-4 is a booster engine.
GWH is correct, New Glenn's second stage uses a vacuum-optimized BE-4 (the optional third stage uses a vacuum-optimized BE-3).

Quote
The 2-stage New Glenn is 270 feet tall, and its second stage is powered by a single vacuum-optimized BE-4 engine. The 3-stage New Glenn is 313 feet tall. A single vacuum-optimized BE-3 engine, burning liquid hydrogen and liquid oxygen, powers its third stage. The booster and the second stage are identical in both variants.
Title: Re: Blue Origin's BE-4 Engine
Post by: Prettz on 03/07/2017 09:26 PM
Methalox appears to be more compatible with simulations than kerolox and hydrolox ever were.
I'm curious why methalox would be easier to simulate than hydrolox. Hydrogen combustion is vastly simpler, isn't it?
Title: Re: Blue Origin's BE-4 Engine
Post by: Space Ghost 1962 on 03/08/2017 12:17 AM
Methalox appears to be more compatible with simulations than kerolox and hydrolox ever were.
I'm curious why methalox would be easier to simulate than hydrolox. Hydrogen combustion is vastly simpler, isn't it?
Note highlighting. Not chemistry. Kinetics. Something to do with decomposition. Don't understand it myself.
Title: Re: Blue Origin's BE-4 Engine
Post by: Rocket Surgeon on 03/08/2017 12:20 AM
Methalox appears to be more compatible with simulations than kerolox and hydrolox ever were.
I'm curious why methalox would be easier to simulate than hydrolox. Hydrogen combustion is vastly simpler, isn't it?

I'm not sure but I think it's because, scientifically speaking, hydrogen is a pain in the ass and just likes to be different...
Title: Re: Blue Origin's BE-4 Engine
Post by: Port on 03/08/2017 12:51 AM
Methalox appears to be more compatible with simulations than kerolox and hydrolox ever were.
I'm curious why methalox would be easier to simulate than hydrolox. Hydrogen combustion is vastly simpler, isn't it?

I'm not sure but I think it's because, scientifically speaking, hydrogen is a pain in the ass and just likes to be different...

Nobody said that hydrolox would be more complex to simlulate, i'm pretty sure that the opposite could very well be the case.
Only problem that i could see is that hydrogen tends to tunnel, also energetically speaking through reaction-energy potentials - this can however be calculated beforehand through more sofisticated dft-methods (or some sort thereof)

Whatever happens when hydrogen is combusted also happens when methane is combusted and then some (actually some huge stuff more due to the bonding-complexity of carbon).
There was a talk on how SpX uses simulation and they literally calculate every possible reaction, intermediate, sidereaction and so on - the CH4+O2 system has way north of 50 possible reaction mechanisms that take place between CH4+3 O2 -> 2 H2O+CO2 and this is what makes it really hard to accurately calculate.

The H2+O2 System is arguably much simpler, there are some radical-paths, mainly over HOO*, OH*- and the likes but nothing out of the super-ordinary.

complex carbon molecules are a whole other story, the complexity from the source materials alone is mindboggeling, the number of possible combinations should go something completely ridiculous potentiated with number of variable species, number of atoms, number of different atoms, number of possible radicals, then there is the problem that there are aromatic species involved and so on and so on, it's outright impossible to calculate as a first-order guess on my part
Title: Re: Blue Origin's BE-4 Engine
Post by: savuporo on 03/10/2017 02:37 AM
https://arstechnica.com/science/2017/03/blue-origins-new-engine-isnt-good-enough-for-some-congressmen/
Title: Re: Blue Origin's BE-4 Engine
Post by: FutureSpaceTourist on 03/10/2017 03:18 AM
https://arstechnica.com/science/2017/03/blue-origins-new-engine-isnt-good-enough-for-some-congressmen/

I think that belongs in the space policy section - its politics, not about the technical merits of one engine vs another.
Title: Re: Blue Origin's BE-4 Engine
Post by: xanmarus on 03/10/2017 09:29 AM
I think that belongs in the space policy section - its politics, not about the technical merits of one engine vs another.
I believe we need swearing section for such links.
Title: Re: Blue Origin's BE-4 Engine
Post by: rsdavis9 on 03/10/2017 12:29 PM
So where is the BE-4 manufactured?
Texas near their launch site?
Washington state. I think there is a blue origin facility there?
Title: Re: Blue Origin's BE-4 Engine
Post by: rsdavis9 on 03/10/2017 12:35 PM
So does everybody think BE-4 will achieve X before raptor.
Test fire on stand.
Flight in some sort of vehicle.
Title: Re: Blue Origin's BE-4 Engine
Post by: envy887 on 03/10/2017 03:20 PM
So does everybody think BE-4 will achieve X before raptor.
Test fire on stand.
Flight in some sort of vehicle.

Raptor already had an all-up (but sub-scale) test fire on stand. BE-4 will "soon", probably in the next few months. BE-4 should do orbital flights first, though it will be interesting to see if either makes it into a sub-orbital test vehicle.
Title: Re: Blue Origin's BE-4 Engine
Post by: TrevorMonty on 03/10/2017 06:07 PM
So does everybody think BE-4 will achieve X before raptor.
Test fire on stand.
Flight in some sort of vehicle.

Raptor already had an all-up (but sub-scale) test fire on stand. BE-4 will "soon", probably in the next few months. BE-4 should do orbital flights first, though it will be interesting to see if either makes it into a sub-orbital test vehicle.
Likely to fly in Vulcan first. Nice of ULA to help pay for development and test fly it for Blue.
Title: Re: Blue Origin's BE-4 Engine
Post by: russianhalo117 on 03/10/2017 06:54 PM
So where is the BE-4 manufactured?
Texas near their launch site?
Washington state. I think there is a blue origin facility there?

Washington State for Dev, Qual, and pre production flight LRE's. Full production LRE's and static testing will shift to Florida in the coming years once BO's facilities in the KSC/CCAFS area come online.
Title: Re: Blue Origin's BE-4 Engine
Post by: rsdavis9 on 03/10/2017 08:12 PM
So where is the BE-4 manufactured?
Texas near their launch site?
Washington state. I think there is a blue origin facility there?

Washington State for Dev, Qual, and pre production flight LRE's. Full production LRE's and static testing will shift to Florida in the coming years once BO's facilities in the KSC/CCAFS area come online.

So they do their static fires of the engines there currently?
Anybody have eyes on their facility? Or ears?
Title: Re: Blue Origin's BE-4 Engine
Post by: meberbs on 03/10/2017 08:36 PM
So where is the BE-4 manufactured?
Texas near their launch site?
Washington state. I think there is a blue origin facility there?

Washington State for Dev, Qual, and pre production flight LRE's. Full production LRE's and static testing will shift to Florida in the coming years once BO's facilities in the KSC/CCAFS area come online.
Not sure your source for this information. While Blue Origin has some engine test facilities in Washington, the current plan for BE-4 as I understand it is:

-initial production in Washington State
-initial testing in Texas
-full rate production location TBD (Florida and Washington State were both in the running last I heard, maybe others)
-full rate testing takes place at a converted LC-11 in Florida
Title: Re: Blue Origin's BE-4 Engine
Post by: rsdavis9 on 03/10/2017 08:45 PM
So if initial testing is in texas. It looks to be near impossible for any observers. It appears to be in the middle of nowhere.
Title: Re: Blue Origin's BE-4 Engine
Post by: leaflion on 03/11/2017 03:50 AM
Actually its about 1 hour's drive beyond the middle of nowhere.

Title: Re: Blue Origin's BE-4 Engine
Post by: Damon Hill on 03/11/2017 08:10 PM
So where is the BE-4 manufactured?
Texas near their launch site?
Washington state. I think there is a blue origin facility there?

Kent, Washington to be precise, about five or six miles up the road from me.  In the middle of industrial parks and warehouses.  Has to be production only, they couldn't test fire an engine that large and not break windows.  There is something in the back of the BO facility that suggests they could test small thrusters there, but I don't know for certain.

--Damon
Title: Re: Blue Origin's BE-4 Engine
Post by: meberbs on 03/12/2017 03:46 PM
So where is the BE-4 manufactured?
Texas near their launch site?
Washington state. I think there is a blue origin facility there?

Kent, Washington to be precise, about five or six miles up the road from me.  In the middle of industrial parks and warehouses.  Has to be production only, they couldn't test fire an engine that large and not break windows.  There is something in the back of the BO facility that suggests they could test small thrusters there, but I don't know for certain.

--Damon
You are correct, they have an engine test facility in the back that they have used in the past, but there is no way they would test something like BE-4 there.
Title: Re: Blue Origin's BE-4 Engine
Post by: Navier–Stokes on 03/20/2017 12:12 PM
Quote from: Underappreciated Engine Components – Bearings
Although the BE-4 turbopump is smaller than your refrigerator, it generates 70,000 horsepower from a turbine running at nearly 19,000 revolutions per minute that pumps cryogenic propellants to pressures just under 5,000 pounds per square inch. To react the forces generated by the rotating turbine and impellers inside the pump, production rocket turbopumps to date have used traditional ball and roller bearings. For BE-4, we’re doing something different – we’re using hydrostatic bearings.

A hydrostatic bearing relies on a fluid film supplied by a high-pressure source to provide support for the shaft and cause it to float without contacting the static structure except at startup and shutdown. The BE-4 main turbopump uses hydrostatic journal bearings for radial support and hydrostatic axial bearings to carry axial thrust. The system is bootstrapped. The high pressure fluid films for the bearings are supplied by the propellants themselves – liquefied natural gas and liquid oxygen – tapped off from the pump discharge flows.
Material selection is a critical consideration for this approach, as there is physical contact between the bearing surfaces during the start transient before the fluid film is fully established and during the shutdown transient as the fluid film dissipates. With lab-scale tests and full-scale bearing rig tests using actual pump hardware, we evaluated over 20 material combinations in over a hundred tests, leading to our baseline material and coating choices.

Extensive rotordynamic and computational fluid dynamics analyses have shown the feasibility of this design, and recent powerpack tests confirmed that this approach works during the startup and shutdown transients – the most critical phases. The shaft orbit plot below shows that the turbopump lifts off smoothly and centers during a typical start transient, demonstrating a smooth ride on a film of propellant.

Why do we go to all this trouble instead of just using traditional bearings? Engine life. We’re relentlessly focused on reusability, and properly designed hydrostatic bearings offer the potential for longer engine life without refurbishment. This is one of the many engineering decisions we’ve made that we hope will lead to reusability – not just in principle – but to practical, operational reusability. If “reusability” requires significant refurbishment, inspection, and re-validation between flights, then it simply won’t lead to the far lower launch costs we need to achieve our vision of millions of people living and working in space.

We’ll keep you up to date as our testing progresses in the coming weeks.

Gradatim Ferociter!

Jeff Bezos
Title: Re: Blue Origin's BE-4 Engine
Post by: TrevorMonty on 03/20/2017 02:10 PM
Great post. Nice to see great engineering that Blue are doing.
Title: Re: Blue Origin's BE-4 Engine
Post by: baldusi on 03/20/2017 05:35 PM
Wow! This is the first engine I know that actually implements hydrostatic bearings. I think it was part of the IPD demonstrated technologies. But actually implementing it on a flight certified reusable engine is quite an accomplishment.
Title: Re: Blue Origin's BE-4 Engine
Post by: FutureSpaceTourist on 03/20/2017 05:44 PM
Interesting example of just how seriously Blue are working on ease of re-use from the start. I guess that's what having serious capital behind them, with no current pressure to generate a ROI, enables.

The contrast with SpaceX, who had to generate revenue much sooner, is substantial. I must admit though that I feel more comfortable with SpaceX's (forced) simpler and more iterative approach. Really looking forward to seeing how the imminent BE-4 tests go.
Title: Re: Blue Origin's BE-4 Engine
Post by: HMXHMX on 03/20/2017 06:30 PM
Wow! This is the first engine I know that actually implements hydrostatic bearings. I think it was part of the IPD demonstrated technologies. But actually implementing it on a flight certified reusable engine is quite an accomplishment.

The DARMA CHASE-10 implemented hydrostatic bearings as an upgrade to their conventional bearings about five years ago, but I don't know if they fired an integrated engine with them or not.

http://www.darmatechnology.com/tpa.html

Edit: spelling
Title: Re: Blue Origin's BE-4 Engine
Post by: Jim on 03/20/2017 06:36 PM
I must admit though that I feel more comfortable with SpaceX's (forced) simpler and more iterative approach.

Why?
Title: Re: Blue Origin's BE-4 Engine
Post by: Toast on 03/20/2017 06:49 PM
I must admit though that I feel more comfortable with SpaceX's (forced) simpler and more iterative approach.

In a way, the BE-4 is more of a simple, iterative approach than SpaceX's Raptor design. Raptor is a bleeding-edge engine that relies on a lot of new technologies and designs, while the BE-4 is relatively simple, as far as staged-combustion engines go. That should make the BE-4 a lot easier to iterate on than the Raptor.
Title: Re: Blue Origin's BE-4 Engine
Post by: guckyfan on 03/20/2017 06:54 PM
In a way, the BE-4 is more of a simple, iterative approach than SpaceX's Raptor design. Raptor is a bleeding-edge engine that relies on a lot of new technologies and designs, while the BE-4 is relatively simple, as far as staged-combustion engines go. That should make the BE-4 a lot easier to iterate on than the Raptor.

In what way? We must differentiate between iterations in the design phase and development after the first generation of flight ready engines.

I agree that improvements on capability should be a lot easier on BE-4 than on Raptor, just like interations were frequent and significant for Merlin. Raptor seems much harder to improve capabilities.

But iterations during design are a totally different thing.
Title: Re: Blue Origin's BE-4 Engine
Post by: FutureSpaceTourist on 03/20/2017 07:07 PM
I must admit though that I feel more comfortable with SpaceX's (forced) simpler and more iterative approach.

Why?

Because I think there's quite a learning curve to building a successful orbital vehicle. So having a first orbital vehicle that's more capable (in terms of payload and re-use) than many other existing LVs feels riskier. SpaceX learnt some hard lessons with F1, will Blue do something similar with NG?

They obviously think NS has taught them enough and maybe they will have a very incremental test approach with NG. I guess I'm nervous about how easily their BE-3 and NS experience extrapolates to BE-4 and NG.
Title: Re: Blue Origin's BE-4 Engine
Post by: LouScheffer on 03/20/2017 07:28 PM
Quote from: Underappreciated Engine Components – Bearings
[Hydrostatic bearings...]

Why do we go to all this trouble instead of just using traditional bearings? Engine life. We’re relentlessly focused on reusability, and properly designed hydrostatic bearings offer the potential for longer engine life without refurbishment. This is one of the many engineering decisions we’ve made that we hope will lead to reusability – not just in principle – but to practical, operational reusability. If “reusability” requires significant refurbishment, inspection, and re-validation between flights, then it simply won’t lead to the far lower launch costs we need to achieve our vision of millions of people living and working in space.

For comparison, the SSME pump bearings were specified to have a 7.5 hour (450 minute) life before refurbishement. (https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20100023061.pdf).  That's on the order of 100 flights of a first stage.  So if the goal is to have a longer life, they must be planning lots of uses.  But it also seem to me (though I am certainly not a bearing engineer) that these might be easier to build and inspect, which might be part of their appeal.
Title: Re: Blue Origin's BE-4 Engine
Post by: FutureSpaceTourist on 03/20/2017 07:33 PM
Quote
@spacecom Hydrostatic bearings were one of the innovations that led us to pick the engine.  Thrilled to see them working 😌

https://twitter.com/george_sowers/status/843919844135260161 (https://twitter.com/george_sowers/status/843919844135260161)
Title: Re: Blue Origin's BE-4 Engine
Post by: Toast on 03/20/2017 08:31 PM
In what way? We must differentiate between iterations in the design phase and development after the first generation of flight ready engines.

I agree that improvements on capability should be a lot easier on BE-4 than on Raptor, just like interations were frequent and significant for Merlin. Raptor seems much harder to improve capabilities.

But iterations during design are a totally different thing.

Sorry if I wasn't very clear, I meant it in the sense you did--improvements after the initial design. A big part of Merlin's success was it's relative simplicity, which allowed SpaceX to manufacture it quickly and incorporate more frequent changes. Similarly, I think BE-4's simpler engine cycle will make design modifications easier in the future in comparison to Raptor's more complicated full-flow staged combustion design.
Title: Re: Blue Origin's BE-4 Engine
Post by: AncientU on 03/20/2017 10:10 PM
Great post. Nice to see great engineering that Blue are doing.

Looks like we have entered a (welcome) new era of openness from Jeff Bezos and Blue Origins!
Title: Re: Blue Origin's BE-4 Engine
Post by: TrevorMonty on 03/20/2017 10:50 PM
In what way? We must differentiate between iterations in the design phase and development after the first generation of flight ready engines.

I agree that improvements on capability should be a lot easier on BE-4 than on Raptor, just like interations were frequent and significant for Merlin. Raptor seems much harder to improve capabilities.

But iterations during design are a totally different thing.

Sorry if I wasn't very clear, I meant it in the sense you did--improvements after the initial design. A big part of Merlin's success was it's relative simplicity, which allowed SpaceX to manufacture it quickly and incorporate more frequent changes. Similarly, I think BE-4's simpler engine cycle will make design modifications easier in the future in comparison to Raptor's more complicated full-flow staged combustion design.
I don't think Blue will be modifying BE4 for improved performance. Increased reliability and easier maintenance yes.

Both NG and Vulcan (ACES) will have enough performance for most satellites without needing SRBs.
Title: Re: Blue Origin's BE-4 Engine
Post by: russianhalo117 on 03/21/2017 12:51 AM
I must admit though that I feel more comfortable with SpaceX's (forced) simpler and more iterative approach.

In a way, the BE-4 is more of a simple, iterative approach than SpaceX's Raptor design. Raptor is a bleeding-edge engine that relies on a lot of new technologies and designs, while the BE-4 is relatively simple, as far as staged-combustion engines go. That should make the BE-4 a lot easier to iterate on than the Raptor.
do you have proof for your statements as FFSC is not new and has been tested but not flown because of challenges from previous manufacturing techniques and others.
First ever FFSC to complete testing was the RD-270 for the cancelled UR-700 and UR-900 programmes. Next was integrated powerhead demonstrator (IPD) by Rocketdyne and last up and in testing is Raptor.
Title: Re: Blue Origin's BE-4 Engine
Post by: envy887 on 03/21/2017 02:21 AM
I must admit though that I feel more comfortable with SpaceX's (forced) simpler and more iterative approach.

In a way, the BE-4 is more of a simple, iterative approach than SpaceX's Raptor design. Raptor is a bleeding-edge engine that relies on a lot of new technologies and designs, while the BE-4 is relatively simple, as far as staged-combustion engines go. That should make the BE-4 a lot easier to iterate on than the Raptor.
do you have proof for your statements as FFSC is not new and has been tested but not flown because of challenges from previous manufacturing techniques and others.
First ever FFSC to complete testing was the RD-270 for the cancelled UR-700 and UR-900 programmes. Next was integrated powerhead demonstrator (IPD) by Rocketdyne and last up and in testing is Raptor.

The level of integration used in Raptor is new, thanks to additive manufacturing. And the chamber pressure is new.

BE-4 has a more modular design and lower chamber pressure. Though some things are new with it as well.
Title: Re: Blue Origin's BE-4 Engine
Post by: Dante80 on 03/21/2017 05:29 AM

do you have proof for your statements as FFSC is not new and has been tested but not flown because of challenges from previous manufacturing techniques and others.
First ever FFSC to complete testing was the RD-270 for the cancelled UR-700 and UR-900 programmes. Next was integrated powerhead demonstrator (IPD) by Rocketdyne and last up and in testing is Raptor.

Both engines are new, and there is a lot of risk to retire and work to be done before we see them fly. The difference between the two simply lies on the design goals that each company has decided to pursue.

And the design goals for Raptor are simply ridiculous.
Title: Re: Blue Origin's BE-4 Engine
Post by: TrevorMonty on 03/21/2017 08:31 AM
Trying estimate BE4 annual production rate, here my guesses.
One NG per year till they have fleet of 4 =7 engines.
 1 per flight for 2nd stage allow 6 flights = 6 engines.
Vulcan 5 flights = 10 engines.
Total 23.
When fleet of NG are ready they would start on NA at 21 engine per booster +3 for reuseable 2nd stage. One every 2 years so 12 engines. NB reusable NG 2nd stage maybe flying with few expendable so 4-6 a year. Vulcan maybe up to 10 flights but they should be recovering engines.

20 a year for next 10yrs is not unrealistic.
Title: Re: Blue Origin's BE-4 Engine
Post by: AncientU on 03/21/2017 12:25 PM
In what way? We must differentiate between iterations in the design phase and development after the first generation of flight ready engines.

I agree that improvements on capability should be a lot easier on BE-4 than on Raptor, just like interations were frequent and significant for Merlin. Raptor seems much harder to improve capabilities.

But iterations during design are a totally different thing.

Sorry if I wasn't very clear, I meant it in the sense you did--improvements after the initial design. A big part of Merlin's success was it's relative simplicity, which allowed SpaceX to manufacture it quickly and incorporate more frequent changes. Similarly, I think BE-4's simpler engine cycle will make design modifications easier in the future in comparison to Raptor's more complicated full-flow staged combustion design.
I don't think Blue will be modifying BE4 for improved performance. Increased reliability and easier maintenance yes.

Both NG and Vulcan (ACES) will have enough performance for most satellites without needing SRBs.

There is more to the envisioned role for NG than satellites*.

*In NG's early days, satellite constellations will be launched (hopefully).  Their first launches will be for OneWeb, for instance, with 80 satellites per launch.  With a constellation of small sats, there is no longer a 'satellite' based performance requirement as the constellation launches are almost 'infinitely' divisible payloads... more like propellant than today's GTO payloads.
Title: Re: Blue Origin's BE-4 Engine
Post by: Jim on 03/21/2017 01:20 PM
With a constellation of small sats, there is no longer a 'satellite' based performance requirement as the constellation launches are almost 'infinitely' divisible payloads... more like propellant than today's GTO payloads.

Wrong.  GSO comsats will still drive LV performance and fairing sizing.
Title: Re: Blue Origin's BE-4 Engine
Post by: Toast on 03/21/2017 01:54 PM
do you have proof for your statements as FFSC is not new and has been tested but not flown because of challenges from previous manufacturing techniques and others.

I think you're interpreting my statement a bit more rigidly than I intended it. All I meant was that oxygen-rich staged combustion in the BE-4 is a simpler cycle than the full flow staged combustion in Raptor. It is, in the words of Bezos, a "medium-performing version of a high-performing architecture". Bezos contends (and I generally agree) that fighting for that extra bit of Isp makes the engine significantly more complex and expensive, and complexity means that the design, manufacturing, and future upgrades are more difficult. I'm not saying that BE-4 is without challenges (or conversely, that Raptor or FFSC in general is not a good engine design or not worth the extra effort), just that I think that the BE-4 approach will probably provide for easier manufacturing and upgrading as compared to a more complicated cycle.
Title: Re: Blue Origin's BE-4 Engine
Post by: strangequark on 03/21/2017 02:30 PM
Depends. SpaceX is pushing FFSC to the max, to try to hit that 4500psia chamber pressure. You could dial it back, match BE-4's 2000psia chamber pressure, while having markedly lower turbine inlet temperatures and eliminating the interpropellant seal package. Doing very, very rough scaling calcs, you could probably hit the same chamber pressure with a turbine inlet of 500-600°F, versus something around 1200-1400°F.
Title: Re: Blue Origin's BE-4 Engine
Post by: baldusi on 03/21/2017 05:28 PM
I think that you have to understand the difference between using unproven technologies and an unproven cycle. The FFSC is a bit more complicated, yes. But not as much as people have stated. The power balance is much simpler, you don't have to worry about interseals, and you can scale the cycle up and down in Pc/thrust and/or O/F as you want.
Regarding the technologies, both companies are making heavy use of FEM, 3D printing and new hot-oxygen resistant alloys. Blue even has implemented hydrostatic bearing. So, I don't think we know enough regarding the specifics of each to say that Blue has lower technologies risk. It's probable that they have lower rocket cycle risk. But again, there's so little experience with FFSC, that it might just happen to be an "easier" cycle in the long run, albeit initially more expensive.
What we know for sure is that Raptor will be a performance curve-breaking design without a schedule pressure, while BE-4 will be a "good enough" design with a very strict schedule. And that is what I think it's the actual difference: the requirements. SpaceX accepted a lot risks and aggressive requirements because they are not on a clock. And BE-4 tried to curb risk as much as possible to cover their reduced schedule margin.
Title: Re: Blue Origin's BE-4 Engine
Post by: sdsds on 03/21/2017 08:04 PM
[...] the actual difference: the requirements. SpaceX accepted a lot risks and aggressive requirements because they are not on a clock. And BE-4 tried to curb risk as much as possible to cover their reduced schedule margin.

Thank-you, this is very good analysis. Risk tolerance and ways to reduce risk always seem like vital topics in innovative engineering projects!

A minor point: I think you over-state the case slightly by saying they tried to reduce risk "as much as possible." Just slightly differently phrased: I bet they tried to reduced risk only as much as needed to meet the schedule requirement!
Title: Re: Blue Origin's BE-4 Engine
Post by: Space Ghost 1962 on 03/21/2017 08:50 PM
SpaceX accepted a lot risks and aggressive requirements because they are not on a clock. And BE-4 tried to curb risk as much as possible to cover their reduced schedule margin.
Exactly. For the initial success.

BTW, none of these engine designs have advanced to the point of reliability/wear/reuse. The first indications of this will come at the earliest after major firings of these engines. Then we'll see the remediations of each design, how well they work against design goals. That's when you know what you've gotten.

BE4 is a fast to market, low development risk engine. Raptor is an all out, long ranged gamble. AR1 is a RD180 "good enough" rival. Of the three, the first two have far more riding on what follows than the third does.
Title: Re: Blue Origin's BE-4 Engine
Post by: baldusi on 03/22/2017 10:52 AM
Well, I hope that Raptor will be as important as the V-2 and RD-170 engines. Both had such a legacy that dominated for decades the rocket engine design. Blue is not still ready to make such a breakthough, yet. BE-4, I think, will be their RD-107/Merlin 1 workhorse engine. I expect it to be extremely successful. But for really bleeding edge engine, I expect the next engine, probably to be used on the New Armstrong.
Title: Re: Blue Origin's BE-4 Engine
Post by: TrevorMonty on 03/22/2017 03:31 PM
Well, I hope that Raptor will be as important as the V-2 and RD-170 engines. Both had such a legacy that dominated for decades the rocket engine design. Blue is not still ready to make such a breakthough, yet. BE-4, I think, will be their RD-107/Merlin 1 workhorse engine. I expect it to be extremely successful. But for really bleeding edge engine, I expect the next engine, probably to be used on the New Armstrong.
The BE4 should be good enough for NA, will just need more >20. By using BE4, NA will fly with a proven engine and production of NA can start as soon as NG fleet as been built.

Title: Re: Blue Origin's BE-4 Engine
Post by: Wolfram66 on 03/22/2017 03:52 PM
I think that you have to understand the difference between using unproven technologies and an unproven cycle. The FFSC is a bit more complicated, yes. But not as much as people have stated. The power balance is much simpler, you don't have to worry about interseals, and you can scale the cycle up and down in Pc/thrust and/or O/F as you want.
Regarding the technologies, both companies are making heavy use of FEM, 3D printing and new hot-oxygen resistant alloys. Blue even has implemented hydrostatic bearing. So, I don't think we know enough regarding the specifics of each to say that Blue has lower technologies risk. It's probable that they have lower rocket cycle risk. But again, there's so little experience with FFSC, that it might just happen to be an "easier" cycle in the long run, albeit initially more expensive.
What we know for sure is that Raptor will be a performance curve-breaking design without a schedule pressure, while BE-4 will be a "good enough" design with a very strict schedule. And that is what I think it's the actual difference: the requirements. SpaceX accepted a lot risks and aggressive requirements because they are not on a clock. And BE-4 tried to curb risk as much as possible to cover their reduced schedule margin.
What happens if there is cavitation in LOX or LNG flow supplying the hydrostatic bearings?
Title: Re: Blue Origin's BE-4 Engine
Post by: baldusi on 03/22/2017 04:12 PM
(...)
What happens if there is cavitation in LOX or LNG flow supplying the hydrostatic bearings?
RUD, I suppose. But please remember that you are talking about a very small amount of high pressure liquid. Cavitation should be the least of the problems. Start up sequence seems much more problematic.
Title: Re: Blue Origin's BE-4 Engine
Post by: HMXHMX on 03/22/2017 04:40 PM
(...)
What happens if there is cavitation in LOX or LNG flow supplying the hydrostatic bearings?
RUD, I suppose. But please remember that you are talking about a very small amount of high pressure liquid. Cavitation should be the least of the problems. Start up sequence seems much more problematic.

Baldusi is correct; essentially all the wear with such bearings happens as they "liftoff" during the spin up, when pressures and flow are lower than the design operating points.  What that ends up meaning is that number of starts-stops are life determining, not run time.
Title: Re: Blue Origin's BE-4 Engine
Post by: ZachS09 on 03/22/2017 04:40 PM
I thought cavitation results in an early engine shutdown as seen in the Delta IV Heavy demo flight in December 2004.
Title: Re: Blue Origin's BE-4 Engine
Post by: Jim on 03/22/2017 05:45 PM
I thought cavitation results in an early engine shutdown as seen in the Delta IV Heavy demo flight in December 2004.

The cavitation wasn't in the engines but high up in the feed line and the cavitation "bubbles' were detected and erroneously perceived as an empty feed line therefore signaling shutdown.
Title: Re: Blue Origin's BE-4 Engine
Post by: AncientU on 03/22/2017 05:50 PM
Quote
At CSIS #SpaceSecurity event, Blue Origin’s Brett Alexander says first BE-4 engine hotfire test “coming up soon.”
https://twitter.com/jeff_foust

Quote
New @CSIS report: If the BE-4 engine's hot-fire test is successful, it is the obvious choice to succeed the RD-180.
https://twitter.com/SciGuySpace

Title: Re: Blue Origin's BE-4 Engine
Post by: FutureSpaceTourist on 03/22/2017 06:23 PM
There's a separate thread on the CSIS report: http://forum.nasaspaceflight.com/index.php?topic=42580.0 (http://forum.nasaspaceflight.com/index.php?topic=42580.0). Its scope is rather wider than BE-4.
Title: Re: Blue Origin's BE-4 Engine
Post by: baldusi on 03/22/2017 06:38 PM
I thought cavitation results in an early engine shutdown as seen in the Delta IV Heavy demo flight in December 2004.
As Jim explained, that was cavitation before the main feedline. But in any case, the RD-68 is a gas generator, thus, a cavitation on the pump inlet would probably mean "bubbles" in the outlet, that run the risk of creating serious instabilities in the Main Combustion Chamber.
In the BE-4, that's a different case since it has staged combustion, so you could have cavitation either in the MCC if the problem was on the fuel side, or the preburner if it was in the oxidizer. And that's where things could get ugly really fast. You don't want cavitation instabilities on your turbines. That could very well mean a RUD.
The interesting thing regarding the hydrostatic bearings, is that they might need to use fuel on the fuel side and oxydizer on the oxi side. Which would need two different inlets of high pressure liquid and add complexity to the interseal. There's a reason the full flow IPD was initially designed for it. It is simpler to do hydrostatic bearings with it.
So, on the BE-4 they might have now one but two failure modes due to hydrostatic liquid starving, one for the fuel and the other for the oxidizer. That trades against greatly expanded burning life (but still limited ignition life).
Title: Re: Blue Origin's BE-4 Engine
Post by: AncientU on 03/22/2017 06:55 PM
There's a separate thread on the CSIS report: http://forum.nasaspaceflight.com/index.php?topic=42580.0 (http://forum.nasaspaceflight.com/index.php?topic=42580.0). Its scope is rather wider than BE-4.

Thanks, didn't see that.
Edited entry to focus on BE-4.
Title: Re: Blue Origin's BE-4 Engine
Post by: Jim on 03/23/2017 12:27 PM
You don't want cavitation on your turbines.

In the pumps and not turbines.   Cavitation doesn't get past the pumps.  It is the lower pressures before the pumps, where is happens.  It never reaches the combustion part of the engine.  Cavitation puts loads on impellers and blades and that what tears up the engine.  Also, severe cavitation could unload the pumps.
Title: Re: Blue Origin's BE-4 Engine
Post by: baldusi on 03/23/2017 04:00 PM
You don't want cavitation on your turbines.

In the pumps and not turbines.   Cavitation doesn't get past the pumps.  It is the lower pressures before the pumps, where is happens.  It never reaches the combustion part of the engine.  Cavitation puts loads on impellers and blades and that what tears up the engine.  Also, severe cavitation could unload the pumps.

I corrected my wording. But are you positive that cavitation at the pump inlet won't generate instabilities in the flow, and thus combustion instabilities on the Mcc?
Title: Re: Blue Origin's BE-4 Engine
Post by: Space Ghost 1962 on 03/23/2017 05:06 PM
You don't want cavitation on your turbines.

In the pumps and not turbines.   Cavitation doesn't get past the pumps.  It is the lower pressures before the pumps, where is happens.  It never reaches the combustion part of the engine.  Cavitation puts loads on impellers and blades and that what tears up the engine.  Also, severe cavitation could unload the pumps.

I corrected my wording. But are you positive that cavitation at the pump inlet won't generate instabilities in the flow, and thus combustion instabilities on the Mcc?

For the pump to compress flow, it decreases the volume of the flow. If the means it employs insures a liquid only density before its final stage of compression, then no gas is present to destabilize the injectors/combustion chamber. That is why there are multiple stages.

If you have a short enough flow path, you will always have gas get through, thus you will risk unstable combustion/detonation.
Title: Re: Blue Origin's BE-4 Engine
Post by: su27k on 03/24/2017 02:13 PM
Haven't seen these posted, this is from reddit thread https://www.reddit.com/r/ula/comments/5xtapc/jeff_bezos_on_twitter_1st_be4_engine_fully/, in which Tory Bruno answered questions about BE-4.

Quote from: Tory Bruno
Quote from: Srekcalp
Is AR1 still going ahead? I thought ULA settled on the BE-4?
The engine downselection will occur after this beauty accomplishes some hot fire test data and retires the combustion instability risk

Quote from: Tory Bruno
Quote from: hqi777
"retires the combustion instability risk."
What does this mean? Can you please elaborate?
Sure.

One of the major risks when you go to a new propellant or a new size is the appearance of combustion instability.

This is a combustion roughness phenomenon typically associated with start-up.

It's very much like the roughness you experience in the winter when you start your car on a cold morning and it idles roughly for awhile.

Except, that there is so much energy involved in a rocket engine, that the vibration and uneven heating effects can literally tear the engine apart.

Tuning the engine's geometry and pressure characteristics can usually resolve this, but not always.
Because BE4 is the largest methane engine ever built, combustion instability is the chief technical risk.

Quote from: Tory Bruno
Quote from: brickmack
Its ISP is known to be about the same or perhaps a bit lower than RD-180, though I expect that will increase after they get experience reusing them and are confident enough to de-nerf the design (since it was intentionally derated for reusability)
Sound Systems Engineering adds performance and weight growth allowances (margins). These are cashed in as the design matures. When you do it right, the product gets "better" as you move through its development.

This keeps the rest of the system from being disrupted and redesigned as you move through maturity
Title: Re: Blue Origin's BE-4 Engine
Post by: Chasm on 03/24/2017 04:30 PM
There was a bit of info in the CSIS panel discussion (https://www.youtube.com/watch?v=lftY2-NKX0E?t=17221).

Blue itself is going with New Glenn after the human space flight market. Most of the talking point were about Vulcan.
Confirmed that the spec changed from 400k to 550k lbf. Should Blue stop to supply engines ULA has the first right of refusal. IP, tooling, factory and so on. There is a lot of talk with the Air Force about the BE-4, requirements and insights.

The engine is on the test stand, and it is a flight weight engine. That was a sudden bought of excitement in a tame environment, the ARJ panelist tired to talk Blues progress down ("no factory" "just a prototype") and got shut down hard. link (https://www.youtube.com/watch?v=lftY2-NKX0E?t=19940)

Lots of fun between the lines with "paid for out of pocket" vs "getting lots of government money should buy influence". There were some more points but I did not keep a list.
Title: Re: Blue Origin's BE-4 Engine
Post by: Navier–Stokes on 03/24/2017 08:05 PM
There was a bit of info in the CSIS panel discussion (https://www.youtube.com/watch?v=lftY2-NKX0E?t=17221).

Blue itself is going with New Glenn after the human space flight market. Most of the talking point were about Vulcan.
Confirmed that the spec changed from 400k to 550k lbf. Should Blue stop to supply engines ULA has the first right of refusal. IP, tooling, factory and so on. There is a lot of talk with the Air Force about the BE-4, requirements and insights.

The engine is on the test stand, and it is a flight weight engine. That was a sudden bought of excitement in a tame environment, the ARJ panelist tired to talk Blues progress down ("no factory" "just a prototype") and got shut down hard. link (https://www.youtube.com/watch?v=lftY2-NKX0E?t=19940)

Lots of fun between the lines with "paid for out of pocket" vs "getting lots of government money should buy influence". There were some more points but I did not keep a list.

The comments by Brett Alexander (Director of Business Development & Strategy at Blue Origin) begin at 5h9m17s.

https://www.youtube.com/watch?v=lftY2-NKX0E&feature=youtu.be&t=5h9m17s
Title: Re: Blue Origin's BE-4 Engine
Post by: DJPledger on 03/26/2017 02:12 PM
Well, I hope that Raptor will be as important as the V-2 and RD-170 engines. Both had such a legacy that dominated for decades the rocket engine design. Blue is not still ready to make such a breakthough, yet. BE-4, I think, will be their RD-107/Merlin 1 workhorse engine. I expect it to be extremely successful. But for really bleeding edge engine, I expect the next engine, probably to be used on the New Armstrong.
And that possible bleeding edge engine for NA may well be FFSC. BO will need the extra performance of FFSC powering very large rockets to achieve their long term goal of getting millions of people living and working in space. BE-4 is a low risk design to meet ULA's time constraints. BO will use the experience from BE-4 to go forward with a higher performance engine for NA.
Title: Re: Blue Origin's BE-4 Engine
Post by: wannamoonbase on 03/27/2017 02:43 PM
Well, I hope that Raptor will be as important as the V-2 and RD-170 engines. Both had such a legacy that dominated for decades the rocket engine design. Blue is not still ready to make such a breakthough, yet. BE-4, I think, will be their RD-107/Merlin 1 workhorse engine. I expect it to be extremely successful. But for really bleeding edge engine, I expect the next engine, probably to be used on the New Armstrong.
And that possible bleeding edge engine for NA may well be FFSC. BO will need the extra performance of FFSC powering very large rockets to achieve their long term goal of getting millions of people living and working in space. BE-4 is a low risk design to meet ULA's time constraints. BO will use the experience from BE-4 to go forward with a higher performance engine for NA.

There's nothing low tech or 'just getting by' about a staged combustion liquid methane engine.

FFSC is certainly the sexiest of engine cycles, but SC is no minor accomplishment.

Surely they will learn and improve and maybe develop a new engine after BE-4, I'm not certain they need too.
Title: Re: Blue Origin's BE-4 Engine
Post by: baldusi on 03/27/2017 05:34 PM
Well, I hope that Raptor will be as important as the V-2 and RD-170 engines. Both had such a legacy that dominated for decades the rocket engine design. Blue is not still ready to make such a breakthough, yet. BE-4, I think, will be their RD-107/Merlin 1 workhorse engine. I expect it to be extremely successful. But for really bleeding edge engine, I expect the next engine, probably to be used on the New Armstrong.
And that possible bleeding edge engine for NA may well be FFSC. BO will need the extra performance of FFSC powering very large rockets to achieve their long term goal of getting millions of people living and working in space. BE-4 is a low risk design to meet ULA's time constraints. BO will use the experience from BE-4 to go forward with a higher performance engine for NA.

There's nothing low tech or 'just getting by' about a staged combustion liquid methane engine.

FFSC is certainly the sexiest of engine cycles, but SC is no minor accomplishment.

Surely they will learn and improve and maybe develop a new engine after BE-4, I'm not certain they need too.

All are relative terms. BTW, even within the cycle, there are different levels of sophistication. The RD-170 in the 80s was completely on a league of its own. It was so advanced that nobody could match its performance and capabilities for 30 years. Now, almost everybody has a staged combustion engine. Within the SC engines, BE-4 might have some very advanced technologies, like the previously mentioned hydrostatic bearings and custom 3D printer, but in general it is a conservative engine... when compared to other ORSC.
Yes, you are talking about less than ten groups in the world that can do this sort of engine, so against other engine technology, it is a very sophisticated design. But when compared to what NPO Energomash, KBKhA or SpaceX are designing, it is rather on the conservative side.
Title: Re: Blue Origin's BE-4 Engine
Post by: Lars-J on 03/27/2017 07:45 PM
Surely they will learn and improve and maybe develop a new engine after BE-4, I'm not certain they need too.

They'll never need another engine? That is either incredibly optimistic, or incredibly pessimistic!  ;D
Title: Re: Blue Origin's BE-4 Engine
Post by: Hanno on 03/28/2017 02:06 AM
Well, I hope that Raptor will be as important as the V-2 and RD-170 engines. Both had such a legacy that dominated for decades the rocket engine design. Blue is not still ready to make such a breakthough, yet. BE-4, I think, will be their RD-107/Merlin 1 workhorse engine. I expect it to be extremely successful. But for really bleeding edge engine, I expect the next engine, probably to be used on the New Armstrong.
And that possible bleeding edge engine for NA may well be FFSC. BO will need the extra performance of FFSC powering very large rockets to achieve their long term goal of getting millions of people living and working in space. BE-4 is a low risk design to meet ULA's time constraints. BO will use the experience from BE-4 to go forward with a higher performance engine for NA.

There's nothing low tech or 'just getting by' about a staged combustion liquid methane engine.

FFSC is certainly the sexiest of engine cycles, but SC is no minor accomplishment.

Surely they will learn and improve and maybe develop a new engine after BE-4, I'm not certain they need too.

All are relative terms. BTW, even within the cycle, there are different levels of sophistication. The RD-170 in the 80s was completely on a league of its own. It was so advanced that nobody could match its performance and capabilities for 30 years. Now, almost everybody has a staged combustion engine. Within the SC engines, BE-4 might have some very advanced technologies, like the previously mentioned hydrostatic bearings and custom 3D printer, but in general it is a conservative engine... when compared to other ORSC.
Yes, you are talking about less than ten groups in the world that can do this sort of engine, so against other engine technology, it is a very sophisticated design. But when compared to what NPO Energomash, KBKhA or SpaceX are designing, it is rather on the conservative side.
Who is this "almost everyone" with SC? Raptor and BE-4 don't count yet.
Title: Re: Blue Origin's BE-4 Engine
Post by: Dante80 on 03/28/2017 02:29 AM

Who is this "almost everyone" with SC? Raptor and BE-4 don't count yet.

Staged combustion engines have been used in:
  • Space Shuttle (https://en.wikipedia.org/wiki/Space_Shuttle)
  • Atlas III (https://en.wikipedia.org/wiki/Atlas_III)
  • Atlas V (https://en.wikipedia.org/wiki/Atlas_V)
  • Antares (rocket) (http://forum.nasaspaceflight.com/javascript:void(0))
  • N1 (rocket) (http://forum.nasaspaceflight.com/javascript:void(0))
  • H-II (https://en.wikipedia.org/wiki/H-II)
  • H-IIA (https://en.wikipedia.org/wiki/H-IIA)
  • H-IIB (https://en.wikipedia.org/wiki/H-IIB)
  • GSLV (https://en.wikipedia.org/wiki/GSLV)
  • Proton (rocket family) (http://forum.nasaspaceflight.com/javascript:void(0))
  • Zenit (rocket family) (http://forum.nasaspaceflight.com/javascript:void(0))
  • Energia (https://en.wikipedia.org/wiki/Energia)
  • Long March 5,6,7
     (https://en.wikipedia.org/wiki/Long_March_6)
  • Title: Re: Blue Origin's BE-4 Engine
    Post by: Robotbeat on 03/28/2017 03:53 AM
    Proton uses staged combustion? Huh, didn't know that.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Steven Pietrobon on 03/28/2017 04:13 AM
    Also

    Angara
    Dnepr
    Rokot
    Soyuz-2.1b
    Soyuz-2.1v
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Dante80 on 03/28/2017 05:00 AM
    Proton uses staged combustion? Huh, didn't know that.

    ORSC to be exact. In all stages.
    https://en.wikipedia.org/wiki/RD-253 (https://en.wikipedia.org/wiki/RD-253)
    https://en.wikipedia.org/wiki/RD-0210 (https://en.wikipedia.org/wiki/RD-0210)
    https://en.wikipedia.org/wiki/RD-58
    Title: Re: Blue Origin's BE-4 Engine
    Post by: hkultala on 03/28/2017 06:10 AM
    [offtopic]

    Proton uses staged combustion? Huh, didn't know that.

    ORSC to be exact. In all stages.
    https://en.wikipedia.org/wiki/RD-253 (https://en.wikipedia.org/wiki/RD-253)
    https://en.wikipedia.org/wiki/RD-0210 (https://en.wikipedia.org/wiki/RD-0210)
    https://en.wikipedia.org/wiki/RD-58

    Using N2O4 instead of LOX as oxidizer.. how corrosive is N2O4 compared to LOX?

    [/offtopic]
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Kryten on 03/28/2017 07:24 AM
     R-27 also uses ORSC, which means the North Koreans have the technology through their 'Musudan' derivative. There are DoD reports that the Iranians also have tested an R-27 derivative, so they likely have it as well.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Proponent on 03/28/2017 01:19 PM
    In his book History of Liquid Propellant Rocket Engines, (https://books.google.co.uk/books/about/History_of_Liquid_Propellant_Rocket_Engi.html?id=s1C9Oo2I4VYC&redir_esc=y) Sutton states (p. 722) says the first SC engine flew on an R-7 variant in 1961:

    Quote from: G. P. Sutton
    The first Soviet LPRE [liquid-propellant rocket engine] with a staged combustion engine cycle to fly was the S1.5400 LPRE developed at Korolev's DB [design bureau] between 1958 and 1960.  It has also been identified as the 11D33 engine.  The principle of that staged combustion engine cycle was originally demonstrated in ground tests beginning in 1958....  It flew on top of Molniya SLVs and Venera space vehicles, and they in turn were lifted by a variation of the two-stage R-7 ICBM.

    The caption for Fig. 8.11-1 (p. 723), a photo of the S1.5400, adds "Its first satisfactory flight was in an upper stage in 1961."

    EDIT:  Removed extraneous comma in first sentence.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: FutureSpaceTourist on 03/28/2017 01:36 PM
    Eric Berger article on forthcoming BE-4 testing (no new info on date) & it's significance:

    https://arstechnica.com/science/2017/03/heres-why-the-imminent-test-of-jeff-bezos-be-4-rocket-engine-is-a-huge-deal/ (https://arstechnica.com/science/2017/03/heres-why-the-imminent-test-of-jeff-bezos-be-4-rocket-engine-is-a-huge-deal/)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: LouScheffer on 03/28/2017 03:09 PM
    The FFSC is a bit more complicated, yes. But not as much as people have stated. The power balance is much simpler, you don't have to worry about interseals, and you can scale the cycle up and down in Pc/thrust and/or O/F as you want.
    [...]
     But again, there's so little experience with FFSC, that it might just happen to be an "easier" cycle in the long run, albeit initially more expensive.
    Expanding on this, from a pure engineering point of view, it seems like FFSC might be easier.  In addition to the points above:
    (d) Pump design should be easier, and perhaps higher margin, since you can pick the shaft speed independently as part of optimizing each pump for the liquid it is pumping.
    (e) The ORSC technology  is easier for a given chamber pressure.  Since the OR turbine only needs to develop the power to pump the oxygen (and not the fuel) the turbine temperature will be lower for the same chamber pressure.
    (f) The injector is gas-gas.  This seems easier to model, though I don't know if this helps in reducing instability.
    (g) The plumbing seems easier.  You don't need to route everything in and out of a common pump assembly.

    On the downside, startup seems tricky since you need to coordinate the two pumps.  And as pointed out, there is not much experience, so you can't just go and ask someone how they solved the problems you find.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Davidthefat on 03/28/2017 04:06 PM
    Also

    Angara
    Dnepr
    Rokot
    Soyuz-2.1b
    Soyuz-2.1v

    Plus Naro-1 (which is cheating as it's an Angara first stage with a Korean 2nd stage)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: baldusi on 03/28/2017 07:04 PM
    (...)
    Who is this "almost everyone" with SC? Raptor and BE-4 don't count yet.
    Well, you have Energyia, which did the first ORSC (S1.5400) in 1960, and kept on with the RS-58. Then you have NPO Energomash, which have been doing ORSC hypergolics since the RD-253, and of course make the RD-120 and RD-170 family. KBKhA, did the ORSC RD-0210 family of hypergolics and the RD-0124 with kerosen, also did the FRSC RD-0120 among many others. KhIMMASH has the SC RD-56 since late 60s, the S5.98M and did some for ICBM. And let's not forget the Kuznetsov's NK-33.
    Yuzhnoye from Ukraine did the RD-8 in the early 80s and sold blueprints to the Chinese and Indians. The Chinese have the YF-100 and YF-115. The Indians have the CE-7.5 and SCE-200 (yes, the latter still to be operational, but the subsystems have been fired). The British had the Bristol Siddeley Gamma, which was staged combustion, albeit with a much simpler catalystic preburner. MHI of Japan did the LE-7, also SC.
    Then you have the SSME by Rocketdyne. And TRW did designed and validated the preburners for the TR-107, Rocketdyne also did the RS-84 work, and AeroJet had their AJ-500 plus the fuel pump of the IPD. Yes, the Americans used to be the least advanced in SC cycle, but they have a lot of work and a very successful engine in the SSME. As has also been shown, lots of LV use SC engines, and the technology is nowadays widespread. At least as widespread as a highly controlled technology with as few as ten groups/companies with access can be. But Russia, Ukraine, Japan, US, China and India have operational staged combustion engines. And now SpaceX and Blue Origin are getting into this club that's each day less exclusive.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Prettz on 03/29/2017 01:30 AM
    Proton uses staged combustion? Huh, didn't know that.
    Outside of the Soyuz family and Kosmos family, all of the USSR's space launchers going back for some time used nothing but staged combustion engines (naturally excluding pressure-fed upper stages). The two stages of both the R-36 and the UR-100N are ORSC, so that covers Tsyklon 1/2/3, Dnepr, Strela, and Rockot.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: strangequark on 03/29/2017 04:30 AM
    Even some pretty small groups are giving ORSC a go these days.

    https://www.instagram.com/p/BQgeqdfh000/?hl=en (https://www.instagram.com/p/BQgeqdfh000/?hl=en)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Steven Pietrobon on 03/29/2017 06:22 AM
    The British had the Bristol Siddeley Gamma, which was staged combustion, albeit with a much simpler catalystic preburner.

    Gamma was not staged combustion, but gas generator. From

    D. Andrews and H. Sunley, "The Gamma rocket engines for Black Knight," J. British Interplanetary Society, vol. 43, pp. 301-310, July 1990.

    "The steam/oxygen mixture that drives the turbine is accelerated in conical de Laval nozzles, and the exhaust gas is discharged to the atmosphere or space through the casing and exhaust pipe."
    Title: Re: Blue Origin's BE-4 Engine
    Post by: baldusi on 03/29/2017 07:31 PM
    The British had the Bristol Siddeley Gamma, which was staged combustion, albeit with a much simpler catalystic preburner.

    Gamma was not staged combustion, but gas generator. From

    D. Andrews and H. Sunley, "The Gamma rocket engines for Black Knight," J. British Interplanetary Society, vol. 43, pp. 301-310, July 1990.

    "The steam/oxygen mixture that drives the turbine is accelerated in conical de Laval nozzles, and the exhaust gas is discharged to the atmosphere or space through the casing and exhaust pipe."

    I've been looking and have not found a single exhaust on the pictures of the engines.
    https://en.wikipedia.org/wiki/Bristol_Siddeley_Gamma#/media/File:Gamma_2_engine.jpg
    Also, if you look in this article:
    http://orbitalaspirations.blogspot.com.ar/2011/11/black-arrow-britains-satellite-launcher.html
    The schematics of the engine has the catalyzers right as the injection plate.
    And at this image:
    http://www.spaceuk.org/htp/gamma_test.jpg
    I don't see any exhaust port either.
    But the Stentor engines did had an exhaust port.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Steven Pietrobon on 03/30/2017 08:18 AM
    Also, if you look in this article:
    http://orbitalaspirations.blogspot.com.ar/2011/11/black-arrow-britains-satellite-launcher.html
    The schematics of the engine has the catalyzers right as the injection plate.

    That's right. The HTP is pumped into the combustion chamber where it is decomposed and combusted with the fuel. None of this is used to drive the turbine. That's done using a separate steam generator. See attached drawing.

    Quote
    And at this image:
    http://www.spaceuk.org/htp/gamma_test.jpg
    I don't see any exhaust port either.
    But the Stentor engines did had an exhaust port.

    The exhaust port is the tube at the left. The exhaust is perfectly clear since it is just pure steam and oxygen. Don't forget this engine development started in the 1950s!
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Nomic on 03/30/2017 09:42 AM
    Fantastic drawing, central turbine very old school. Can see the lineage from Walter Werke (http://www.walterwerke.co.uk/design/pump.htm) in WWII.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: FutureSpaceTourist on 04/06/2017 12:07 AM
    No surprises here but good to get confirmation and BE-4 test is clearly in (very?) near future:

    http://spacenews.com/bruno-vulcan-engine-downselect-is-blues-to-lose/ (http://spacenews.com/bruno-vulcan-engine-downselect-is-blues-to-lose/)

    Here's an excerpt:

    Quote
    In an interview during the 33rd Space Symposium here, Tory Bruno said that tests of the BE-4 engine, scheduled to begin “very soon” at Blue Origin’s test site in West Texas, are the last major hurdle the engine must clear before ULA decides to use it on Vulcan.

    “The economic factors are largely in place now and the thing that is outstanding is the technical risk,” Bruno said. “That’s why we keep talking about the engine firing.”
    Title: Re: Blue Origin's BE-4 Engine
    Post by: sanman on 04/11/2017 06:21 AM
    So regarding Bezos' article about BE-4 turbopump's hydrostatic bearings, is there any possibility of electromagnetic bearings being used to supplement or assist during the transitional startup or shutdown phases, when the hydrostatic film isn't quite fully formed for hydrostatic integrity?

    Given that the propellants themselves are cryogens, then couldn't they be used to cool some superconductors to produce the magnetic fields necessary to serve as the bearings, in order to mitigate even the briefest momentary wear-and-tear that could occur during the startup or shutdown phases of the turbopump?

    Perhaps that could improve the reliability and extend the lifespan of what is supposed to be a critical part of a reusable system.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Jim on 04/11/2017 03:09 PM
    So regarding Bezos' article about BE-4 turbopump's hydrostatic bearings, is there any possibility of electromagnetic bearings being used to supplement or assist during the transitional startup or shutdown phases, when the hydrostatic film isn't quite fully formed for hydrostatic integrity?

    Given that the propellants themselves are cryogens, then couldn't they be used to cool some superconductors to produce the magnetic fields necessary to serve as the bearings, in order to mitigate even the briefest momentary wear-and-tear that could occur during the startup or shutdown phases of the turbopump?

    Perhaps that could improve the reliability and extend the lifespan of what is supposed to be a critical part of a reusable system.

    No, too complex and wouldn't increase reliability.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: FutureSpaceTourist on 04/11/2017 07:11 PM
    More background on ULA's engine choice and the status of BE-4:

    http://www.defensenews.com/articles/blue-origin-engines-future-rests-on-upcoming-hot-fire-tests (http://www.defensenews.com/articles/blue-origin-engines-future-rests-on-upcoming-hot-fire-tests)

    Includes:

    Quote
    The hot-fire tests will take place over several weeks later this year, allowing Blue Origin to collect data over multiple test events where the power level will gradually be increased and then sustained for longer periods of time.

    “Finally you’re at full power running long enough to be steady state, and you know what you’ve got,” Bruno said. “Then, we will know what we have, and we’ll be able to pick an engine.”
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Dante80 on 04/13/2017 06:36 AM
    I never understood why Bruno uses the "we'll be able to pick an engine" expression. If I understand the subject correctly, there is no contest here. AR-1 was a backup plan (lets say, insurance policy) from the start, and will only be considered if BE-4 utterly fails to achieve its goals. There will be no competition of any kind, especially since ULA will have taken the decision to go forward before AR-1 matures enough for a full engine test fire program.

    If BE-4 tests as designed, ULA will go for it. End of story. At least, that is what I am getting from ULA quotes this last year.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Lars-J on 04/13/2017 06:51 AM
    It is merely a charade to appease influential people and organizations that they are "keeping an open mind" about the AR-1, IMO. Once BE-4 has been tested, they can drop that pretense.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: FutureSpaceTourist on 04/13/2017 08:10 AM
    It is merely a charade to appease influential people and organizations that they are "keeping an open mind" about the AR-1, IMO. Once BE-4 has been tested, they can drop that pretense.

    I think that's slightly overstating it. There has to be a non-zero risk that BE-4 doesn't work, or at least has significant issues requiring some redesign etc. If the BE-4 schedule were to slip significantly, then ULA have a tricky decision to make at some point.

    Obviously though if the BE-4 schedule remains ahead of AR-1 then they just keep going as is.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: guckyfan on 04/13/2017 08:21 AM
    It is merely a charade to appease influential people and organizations that they are "keeping an open mind" about the AR-1, IMO. Once BE-4 has been tested, they can drop that pretense.

    I have that sense that ULAS and BO feel some urgency for getting BE-4 tested. I guess ULA are under pressure to use AR-1 and that pressure will increase when test dates for BE-4 slip. I personally don't doubt BO will get there and even worst case they will probably be ahead of AR-1.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: MP99 on 04/13/2017 09:44 AM


    I never understood why Bruno uses the "we'll be able to pick an engine" expression. If I understand the subject correctly, there is no contest here. AR-1 was a backup plan (lets say, insurance policy) from the start, and will only be considered if BE-4 utterly fails to achieve its goals. There will be no competition of any kind, especially since ULA will have taken the decision to go forward before AR-1 matures enough for a full engine test fire program.

    If BE-4 tests as designed, ULA will go for it. End of story. At least, that is what I am getting from ULA quotes this last year.

    Look at the RS68. It failed to meet its performance goals (an Isp shortfall, IIRC), and the engine was used in that form for years rather than spend the $$$ to fix it.

    Cheers, Martin
    Title: Re: Blue Origin's BE-4 Engine
    Post by: FutureSpaceTourist on 04/13/2017 06:00 PM
    AW reports a bit more detail on planned BE-4 testing:

    Quote
    Blue Origin President Rob Meyerson says full-scale testing of the BE-4 engine developed for the New Glenn will start in 3-8 weeks. The first of three test engines is installed horizontally at the company’s launch and test site in West Texas, he says, and the test campaign is designed to progress relatively quickly.

    "We have two cells side by side, so we can either test the powerpack and an engine or, we can test two powerpacks, two engines. And that is part of a facility buildout that we’ve done over the last year-and-a-half, adding that capacity,” Meyerson says. “The first BE-4 engine is on the stand. The second and third are in the factory, and they’re going to be shipping soon. We really wanted to go into the test program hardware-rich.”

    http://m.aviationweek.com/space/upheaval-space-access-beginning-now (http://m.aviationweek.com/space/upheaval-space-access-beginning-now)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Navier–Stokes on 04/20/2017 03:33 AM
    ULA chief says Blue Origin in driver’s seat for Vulcan engine deal (https://spaceflightnow.com/2017/04/18/ula-chief-says-blue-origin-in-drivers-seat-for-vulcan-engine-deal/)
    Quote
    Despite a delay of several months in the start of full-scale BE-4 testing, Bruno said the Vulcan rocket is still on track for a maiden flight by the end of 2019 if Blue Origin ends up the winner in ULA’s engine test-off.

    “Assuming we can make this decision in a reasonable span of time, yes,” Bruno told reporters on the sidelines of the Space Symposium. “If we’re on the BE-4, it’s a pretty clear schedule. If the BE-4 is not going to work out and we select AR1, they’re further behind, so that puts a little more pressure on that schedule … If we had to select the AR1, I cannot fly it by 2019.”
    Quote
    Development of the BE-4 engine itself is a commercial effort, primarily funded by Blue Origin, with additional investment by ULA. Officials have not disclosed the BE-4’s development cost, but Bruno said new rocket engines of its scale have typically cost about $1 billion to design, test, and certify.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: sanman on 04/25/2017 08:23 PM
    It is merely a charade to appease influential people and organizations that they are "keeping an open mind" about the AR-1, IMO. Once BE-4 has been tested, they can drop that pretense.

    I have that sense that ULAS and BO feel some urgency for getting BE-4 tested. I guess ULA are under pressure to use AR-1 and that pressure will increase when test dates for BE-4 slip. I personally don't doubt BO will get there and even worst case they will probably be ahead of AR-1.

    I know the thread's about BE-4, but what will happen to AR-1 if/when ULA selects BE-4?

    Are there any other customers waiting in the wings for it? Orbital ATK, or somebody?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: woods170 on 04/26/2017 06:21 AM

    I know the thread's about BE-4, but what will happen to AR-1 if/when ULA selects BE-4?

    Are there any other customers waiting in the wings for it? Orbital ATK, or somebody?

    I suggest you take your question to AR-1 thread: https://forum.nasaspaceflight.com/index.php?topic=34944.0
    Title: Re: Blue Origin's BE-4 Engine
    Post by: FutureSpaceTourist on 05/14/2017 10:23 PM
    Quote
    Blue Origin‏ @blueorigin 3m3 minutes ago

    We lost a set of powerpack test hardware on one of our BE-4 test stands yesterday. Not unusual during development.

    https://twitter.com/blueorigin/status/863881495169048576 (https://twitter.com/blueorigin/status/863881495169048576)

    Quote
    Blue Origin‏ @blueorigin 2m2 minutes ago

    That’s why we always set up our development programs to be hardware rich. Back into testing soon. #GradatimFerociter

    https://twitter.com/blueorigin/status/863881837000638464 (https://twitter.com/blueorigin/status/863881837000638464)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Chris Bergin on 05/14/2017 10:29 PM
    No specifics - and I have nothing further, but it's hard to tell how bad that was. There's a difference between something like the occasional engine controller going pop at McGregor and the Antares engine that went boom at Stennis.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: FutureSpaceTourist on 05/14/2017 10:42 PM
    Clearly some powerpack hardware failed in a non-repairable way (hence the 'lost' and reassurrance of being 'hardware rich'). The reference to being back into testing soon is encouraging - hopefully it means Blue don't believe there's a difficult/complex investigation to be done before testing can resume (although 'soon' could still mean months I guess).
    Title: Re: Blue Origin's BE-4 Engine
    Post by: x15_fan on 05/14/2017 10:52 PM
    Clearly some powerpack hardware failed in a non-repairable way (hence the 'lost' and reassurrance of being 'hardware rich'). The reference to being back into testing soon is encouraging - hopefully it means Blue don't believe there's a difficult/complex investigation to be done before testing can resume (although 'soon' could still mean months I guess).

    This is where the rubber meets the road. Up until now Blue has been working quietly at their own pace, now they have chips down on the table. ULA needs that engine else some very large changes are going to have to be made to Vulcan program. ULA is more like gradatim-asap. Welcome to having customers...
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 05/15/2017 12:40 AM
    Have had an ear for news on BE4 bring up. Already had noticed how time was passing silently.

    Not the best of news. Sounds like the engine teams are not having an easy time. What they are attempting, at scale, is a challenge and a half to get through start up sequencing.

    Also anxiety in Colorado over this. Some would like a win ... soon.

    Thank you Blue Origin for letting us know, even when it doesn't work, that's professional of you.

    Let us know also when you achieve more.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: AncientU on 05/15/2017 12:49 AM
    Testing does that when pushing into new territory. 
    Good that they have additional hardware and stands.
    Keep learning and moving forward, Blue.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Kabloona on 05/15/2017 02:57 AM
    For those of us who are not liquid rocket engine experts, can someone please clarify what components typically comprise the powerpack? I assume preburners and turbopumps. What else? Main injector plate?

    Edit: the following NASA blog says the powerpack is basically everything in the engine upstream of the main injector, so I'll assume that's correct.

    https://blogs.nasa.gov/J2X/tag/powerpack-assembly-2/
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 05/15/2017 03:12 AM
    For those of us who are not liquid rocket engine experts, can someone please clarify what components typically comprise the powerpack? I assume preburners and turbopumps. What else? Main injector plate?

    Edit: the following NASA blog says the powerpack is basically everything in the engine upstream of the main injector, so I'll assume that's correct.

    https://blogs.nasa.gov/J2X/tag/powerpack-assembly-2/
    Yes.

    The main issue is likely with the oxygen preburner.

    When you bring up an engine, everything has to sequence right from the start, or you get a fragmentation device.

    In extreme/spectacular cases, it takes the test stand with it.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Kabloona on 05/15/2017 03:20 AM
    For those of us who are not liquid rocket engine experts, can someone please clarify what components typically comprise the powerpack? I assume preburners and turbopumps. What else? Main injector plate?

    Edit: the following NASA blog says the powerpack is basically everything in the engine upstream of the main injector, so I'll assume that's correct.

    https://blogs.nasa.gov/J2X/tag/powerpack-assembly-2/
    Yes.

    Thanks, SG.

    This article from last year is admittedly old, but seems relevant since it discusses preburner combustion and cooling the preburner combustion products sufficiently to protect the turbopump vanes.

    http://www.popsci.com/jeff-bezos-explains-how-blue-origin-will-prevent-its-next-gen-rocket-engine-from-melting

    The closing line from Jeff Bezos may be getting put to the test right now:

    "The ability to do combusting CFD simulations doesn’t eliminate the need for rigorous testing, but it will significantly shorten the test-fail-fix loop on the test stand. "

    I guess we hope their CFD model is good and it was "merely" a startup transient issue as you suggested.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Chasm on 05/15/2017 04:53 AM
    According to this years talks and slides they have tested the BE-4 powerpack to 400klbf. 60+ starts at that level.
    No 550klbf level tests, that was part of this campaign.

    So, what did they test?
    Normal operation vs. edge cases.

    How did they loose the pack?
    Oops, that did not work. Find out what happened and if we have to wait for a modified pack.
    vs.
    BOOM! Well that did not work. Lets check the other cell and order another container of test gear.


    Right about now I'd like a DigitalGlobe account. :)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: guckyfan on 05/15/2017 05:35 AM
    They had announced that a full engine is on the test stand, waiting to be fired. Now they announce a power pack has blown, which I would not see as unusual at this stage. But was this a test of the full engine? Could a full engine test end with only the power pack blown?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Coastal Ron on 05/15/2017 05:51 AM
    Clearly some powerpack hardware failed in a non-repairable way (hence the 'lost' and reassurrance of being 'hardware rich'). The reference to being back into testing soon is encouraging - hopefully it means Blue don't believe there's a difficult/complex investigation to be done before testing can resume (although 'soon' could still mean months I guess).

    I would imagine "soon" also depends on what they think caused the problem.  Hopefully this was a test of what they thought the limits were, or an understandable failure of some kind.

    I do like how they are "hardware rich" though, because that tells me they are OK with breaking things...
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Chasm on 05/15/2017 06:17 AM
    Lost is nicely vague. Covers everything from widely distributed engine and test stand confetti down to a problem that got caught in time to shut down safely but leaves the powerpack (or complete engine) inoperable / a specimen for the materials lab.

    Since they are still deep in development and verification I suppose that all test articles are heavily instrumented. So catching problems is possible, esp. if they had a few successful runs to compare to.


    Was this the first run for the powerpack? 2nd? 20th?
    During normal operation or while verifying characteristics?
    "This should work" vs. "This is unlikely to work, but we need to verify limits."
    Maybe we'll find out in the future.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: edkyle99 on 05/15/2017 01:44 PM
    More important than the "lost" powerpack is the condition of the test stand. 

     - Ed Kyle
    Title: Re: Blue Origin's BE-4 Engine
    Post by: LouScheffer on 05/15/2017 02:22 PM
    Quote
    Blue Origin‏ @blueorigin 3m3 minutes ago

    We lost a set of powerpack test hardware on one of our BE-4 test stands yesterday. Not unusual during development.

    https://twitter.com/blueorigin/status/863881495169048576 (https://twitter.com/blueorigin/status/863881495169048576)

    Not unusual seems an understatement. For example, from Characteristics of Space Shuttle Main Engine failures (https://ntrs.nasa.gov/search.jsp?R=19870058042)
    Quote
    During development and operation of the Space Shuttle Main Engine (SSME), 27 ground test failures of sufficient severity to be termed 'major incident' have occurred.
    Has an engine *ever* been developed without destroying itself several times on the test stand?  "Normal" or "Expected" might be more honest than "Not unusual".
    Title: Re: Blue Origin's BE-4 Engine
    Post by: edkyle99 on 05/15/2017 02:31 PM
    Has an engine *ever* been developed without destroying itself several times on the test stand?  "Normal" or "Expected" might be more honest than "Not unusual".
    Probably not.  During Tom Mueller's recent interview he mentioned blowing up a lot of Merlin 1D engines during development, and that is a "simple" gas generator cycle.

     - Ed Kyle
    Title: Re: Blue Origin's BE-4 Engine
    Post by: baldusi on 05/15/2017 02:48 PM
    AIUI, may be the RS-68 didn't had this sort of failures? I can't think of any high performance and successful engine that didn't had a few martyrs in the name of performance. The big question is if this failure was due to envelop exploration or normal condition. And the test stand status, too. But I'm assuming they had a couple of cells and this was not an RD-170 moment.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: savuporo on 05/15/2017 03:23 PM
    Has an engine *ever* been developed without destroying itself several times on the test stand?..
    Probably a few, XRS-2200 and  J-2X come to mind quickly
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 05/15/2017 03:30 PM
    During Tom Mueller's recent interview he mentioned blowing up a lot of Merlin 1D engines during development
    Makes perfect sense if one is doing a "face shutoff" at the injector.

    And in some ways close to what this test is likely experiencing.

    AIUI, may be the RS-68 didn't had this sort of failures?

    I don't remember a similar case with it. RS68 was supposed to be cheap/easy/fast (like FBC?) by avoiding RS25's SC nightmares. Also, IIRC Fastrac and M-1A didn't have much like this.

    Quote
    I can't think of any high performance and successful engine that didn't had a few martyrs in the name of performance.
    "The bigger they are, the harder they fall."

    Quote
    The big question is if this failure was due to envelop exploration or normal condition.
    Have they achieved "start up" sequencing? Burp test? Short run?

    Suggest far away from either of your two here.

    Quote
    And the test stand status, too.
    Test stands.

    Quote
    But I'm assuming they had a couple of cells and this was not an RD-170 moment.
    Heh. Ouch.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 05/15/2017 10:44 PM
    After 18 charmed months, Blue Origin suffers a setback (https://arstechnica.com/science/2017/05/blue-origin-has-an-accident-on-its-rocket-engine-test-stand/)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: wannamoonbase on 05/16/2017 02:50 AM
    Has an engine *ever* been developed without destroying itself several times on the test stand?  "Normal" or "Expected" might be more honest than "Not unusual".
    Probably not.  During Tom Mueller's recent interview he mentioned blowing up a lot of Merlin 1D engines during development, and that is a "simple" gas generator cycle.

     - Ed Kyle

    And SpaceX wasn't trying to sell their engine to ULA.  Internal project for internal needs.

    With ULA waiting perhaps they had to say something publicly.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Katana on 05/23/2017 04:57 PM
    Has an engine *ever* been developed without destroying itself several times on the test stand?  "Normal" or "Expected" might be more honest than "Not unusual".
    Probably not.  During Tom Mueller's recent interview he mentioned blowing up a lot of Merlin 1D engines during development, and that is a "simple" gas generator cycle.

     - Ed Kyle
    1D? not 1A?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Hauerg on 05/23/2017 05:01 PM
    1D
    Title: Re: Blue Origin's BE-4 Engine
    Post by: jg on 05/27/2017 10:34 PM
    1D
    The valving was unusual for an engine that big.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Star One on 06/07/2017 08:10 AM
    Air Force Moving Forward After Blue Origin 'Setback'

    Quote
    WASHINGTON, D.C. — The Air Force said Monday it is working to "figure out how to progress forward" after a setback in the development of a U.S.-made rocket engine.

    Blue Origin, Amazon (AMZN) founder Jeff Bezos' space company, tweeted May 14 that it lost a "set of powerpack test hardware on one of its BE-4" engine tests. The powerpack pumps the propellant, liquid oxygen and methane, through the engine. The company said it would resume testing "soon."

    Lt. Gen. Arnold Bunch, military deputy in Air Force acquisition, pointed out that the Air Force has agreements with both Blue Origin and Aerojet Rocketdyne (AJRD) to build a replacement for the Russian-made RD-180 engine.

    "We are working with Space and Missile Center to figure out how to progress forward," Bunch told reporters at an Air Force Association breakfast Monday. "We are aware of the Blue Origin setback and we are in dialogue on how to more forward. It is one we are watching because we know the commitment we made to get off of the 180 as quickly as possible."

    http://www.investors.com/news/air-force-moving-forward-after-setback-in-plans-end-russian-rocket-engine-use/
    Title: Re: Blue Origin's BE-4 Engine
    Post by: oldAtlas_Eguy on 06/09/2017 05:35 PM
    From the standpoint of the AF it is about who gets what additional funding in out years FY2018/19/20. Not which engine that they want ULA to use on Vulcan. The AF just wants to make sure that there is a fallback position to the front runner having serious problems that severely the delay the development. That has always been their position and is why the AR-1 is being funded. But now they need to review their funding levels to determine if it still fits with the "new" events.

    Edit added: The statement is full of non-committal items that sound like a PR boilerplate response to the event and its impact for the RD-180 replacement program.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 06/10/2017 02:37 AM
    Correct. Revisiting to assure funding for a "back up".

    Looks like Raptor's initial firing was less challenging than BE-4's is turning out to be. I had wondered about FFSC possibly being easier than ORSC, even though its more parts.

    ORSC historically has not been easy at scale for new engines, taking years to accomplish. You're dealing with partially combusted, highly reactive, high pressure/volume products, barely containable by the engine's materials.

    So while its disappointing it's not an easy engine to finish this stage of its development, it's hardly a surprise either.

    On the AF side, this means both AJR/BO. Remember, AJR has to go through exactly the same with AR-1 that BE-4 is going through now, in a year or two. There is nothing to insure that either/any engine will be deterministic at this stage.

    Which is why there are back-ups, including potentially a solid LV. Financing/plans about them at this stage is what is being referred to.

    IMHO its the most challenging point w/LREs. Next, its on to combustion stability, increasing burn duration, and performance levels/throttling. After that, one begins to understand the engine one designed, as a propulsion system for a vehicle as a reality, warts and all.

    For BO and its indefinite money/schedule, the most troublesome would be having to redesign the powerhead or combustion chamber until things WAD. It might just delay NG a bit.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: MP99 on 06/10/2017 05:04 PM
    Correct. Revisiting to assure funding for a "back up".

    Looks like Raptor's initial firing was less challenging than BE-4's is turning out to be. I had wondered about FFSC possibly being easier than ORSC, even though its more parts.

    ORSC historically has not been easy at scale for new engines, taking years to accomplish. You're dealing with partially combusted, highly reactive, high pressure/volume products, barely containable by the engine's materials.


    According to this years talks and slides they have tested the BE-4 powerpack to 400klbf. 60+ starts at that level.
    No 550klbf level tests, that was part of this campaign.

    A couple of questions, if I may, given that I think (?) Raptor tests are also still at subscale?

    1) how much difference is there between isolated powerpack testing (at 400 klbf), and a failure of a powerpack during all-up testing at whatever power level they would use during their initial integration testing?

    2) I always think of a FFSC engine as being half ORSC, and half FRSC, and therefore think of FFSC as harder than ORSC. Oversimplify, I'm sure.

    Of course, given that BE-4 and Raptor are very similar in thrust, the ORSC engine needs to produce more power in its OR leg (the only preburner leg).

    Does this mean that FFSC allows lower temperatures and a lot less reactivity *everywhere* in that leg, or perhaps just in all the difficult bits?

    Or, maybe avoiding sealing issues separating OR preburner gasses from the fuel leg?

    In general, what are the issues that might make the OR leg of FFSC (Raptor) easier than an ORSC engine (BE-4)?

    Many thanks for any help.

    Cheers, Martin
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 06/11/2017 05:36 AM
    Correct. Revisiting to assure funding for a "back up".

    Looks like Raptor's initial firing was less challenging than BE-4's is turning out to be. I had wondered about FFSC possibly being easier than ORSC, even though its more parts.

    ORSC historically has not been easy at scale for new engines, taking years to accomplish. You're dealing with partially combusted, highly reactive, high pressure/volume products, barely containable by the engine's materials.


    According to this years talks and slides they have tested the BE-4 powerpack to 400klbf. 60+ starts at that level.
    No 550klbf level tests, that was part of this campaign.

    A couple of questions, if I may, given that I think (?) Raptor tests are also still at subscale?

    1) how much difference is there between isolated powerpack testing (at 400 klbf), and a failure of a powerpack during all-up testing at whatever power level they would use during their initial integration testing?
    Considerable.

    The powerpack supplies the injectors/combustion chamber in a full scale test on stand. Before you would be able to supply the flows necessary, but not function in the system as a combustion process, nor work through start-up sequencing. It's not a matter yet of power level, but a matter of function as a combined system. You want to be able to consistently, stablely work through the start-up sequencing and shutdown with the combustion chamber not experiencing detonations. As the combustion chamber increases in size, this becomes more of a challenge.
     
    Quote
    2) I always think of a FFSC engine as being half ORSC, and half FRSC, and therefore think of FFSC as harder than ORSC. Oversimplify, I'm sure.
    Very.

    Keep in mind the mass flows and pressure necessary for the engine's design. The benefit of FFSC is that the sides are at lower pressure/flow than the ORSC's single flow. FFSC is not harder per se as it has more complexity (Raptor's cleverness is in how they keep the complexity down, BE-4's is attempting to limit risk by starting out at a much lower chamber pressure).

    Quote
    Of course, given that BE-4 and Raptor are very similar in thrust, the ORSC engine needs to produce more power in its OR leg (the only preburner leg).
    Nope.

    The fired Raptor is a 1MN, while the BE-4 is to be a 2.4MN engine. And you mean flow/pressure of the OR to inject to the combustion chamber to react to get the power, not power on the OR.

    Quote
    Does this mean that FFSC allows lower temperatures and a lot less reactivity *everywhere* in that leg, or perhaps just in all the difficult bits?
    Less pressure/flow on each OR/FR. Sequencing. (I wonder if experience on Merlin face shutoff helped.)

    Quote
    Or, maybe avoiding sealing issues separating OR preburner gasses from the fuel leg?

    Now we're getting into the cost/complexity issues of how to build a single shaft TP design vs a dual TP design. And more. With FFSC you're not able to have those choice, because of the complexity inherent.

    And issues with how to handle the highly reactive OR mass flow in the ORSC closed cycle design.

    Quote
    In general, what are the issues that might make the OR leg of FFSC (Raptor) easier than an ORSC engine (BE-4)?

    More compartmentalized. Less flow/pressure (although Raptor is a much higher pressure engine than BE-4). You can sequence startup FR then OR instead of all at once. Transients.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: MP99 on 06/11/2017 02:53 PM
    Thanks for a super comprehensive answer.

    Much appreciated as always.

    Cheers, Martin
    Title: Re: Blue Origin's BE-4 Engine
    Post by: woods170 on 06/21/2017 07:53 AM
    After 18 charmed months, Blue Origin suffers a setback (https://arstechnica.com/science/2017/05/blue-origin-has-an-accident-on-its-rocket-engine-test-stand/)

    All depends on POV (http://spacenews.com/if-america-wants-to-succeed-it-needs-to-learn-to-fail-top-general-says/).

    Quote from: Phillip Swarts
    Likewise, Hyten (Gen. John Hyten, the head of U.S. Strategic Command) said he wasn’t pleased with media coverage of Blue Origin’s May accident that destroyed a set of powerpack test hardware for the company’s BE-4 engine.

    “Blue Origin just had a failure. Son of a gun. That’s part of learning,” the general said. “It really upsets me when I see headlines come out in the newspaper after the Blue Origin failure the other day: ‘Blue Origin takes huge step back, big failure!’ I’m going,  ‘no, they’re pushing the envelope.’”
    Title: Re: Blue Origin's BE-4 Engine
    Post by: TrevorMonty on 06/21/2017 10:10 AM
    The odd exploding engine means they pushing hard, as it should.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: woods170 on 06/21/2017 11:37 AM
    The odd exploding engine means they pushing hard, as it should.
    Exactly. Below is a tidbit from the second half of the 1970's, when Rocketdyne was developing the Space Shuttle Main Engine (http://www.alternatewars.com/BBOW/Space_Engines/SSME_Pursuit_Improvement.pdf) (aka RS-25)

    Quote from: Douglas P. Bradley - Pratt&Whitney Rocketdyne
    The first development tests were designed to develop the start sequence (Figure 14). Math models indicated propellant conditions and valve timing would be critical. It took 37 tests and 13 turbopump replacements to achieve minimum power level, which was 50% RPL at the time, and ninety-five tests to reach 100% RPL.

    It is generally assumed that Blue lost their powerpack set during development testing of the BE-4 start-up sequence, so similar to what Rocketdyne went thru with SSME.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: matthewkantar on 06/21/2017 03:44 PM
    To be fair, one cannot expect the press to herald the (most likely explosive) unplanned end to a test like this. Reporting disappointment from all involved in an outcome like this is accurate enough. At least Blue is being a bit more transparent than the other manufacturer in the running.

    Matthew
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 06/21/2017 08:16 PM
    Quote from: Phillip Swarts
    Likewise, Hyten (Gen. John Hyten, the head of U.S. Strategic Command) said he wasn’t pleased with media coverage of Blue Origin’s May accident that destroyed a set of powerpack test hardware for the company’s BE-4 engine.

    “Blue Origin just had a failure. Son of a gun. That’s part of learning,” the general said. “It really upsets me when I see headlines come out in the newspaper after the Blue Origin failure the other day: ‘Blue Origin takes huge step back, big failure!’ I’m going,  ‘no, they’re pushing the envelope.’”
    Sure. Same was true with all the moaning/groaning about the GHe pressurization failures with SX.

    (Had also listened to the schadenfreude from various propulsion teams over the years, including BO's, WRT other engine's arrival at the test stand.)

    The odd exploding engine means they pushing hard, as it should.
    Exactly. Below is a tidbit from the second half of the 1970's, when Rocketdyne was developing the Space Shuttle Main Engine (http://www.alternatewars.com/BBOW/Space_Engines/SSME_Pursuit_Improvement.pdf) (aka RS-25)
    Agree with the analogy.

    However,  BO and SX are private firms, while PWR, AJR, Energia, ... others ... are in a different category with those not-so-limited funds/time.

    Quote
    Quote from: Douglas P. Bradley - Pratt&Whitney Rocketdyne
    The first development tests were designed to develop the start sequence (Figure 14). Math models indicated propellant conditions and valve timing would be critical.
    Whole different time/tools/practices.

    Much worse combustion modelling, mathematics that didnt' handle chaotic processes/leveraging at all well, computational issues with floating point round-off errors that compounded subtle errors.

    Quote
    Quote
    It took 37 tests and 13 turbopump replacements to achieve minimum power level, which was 50% RPL at the time, and ninety-five tests to reach 100% RPL.

    Some of the tests were shown on national TV news broadcasts too. "Is the Shuttle ever going it get off the ground" on might hear in following days at the local watering hole. A burger chief might want to opine on helping out  ::)

    Best I'd say for such was to describe it as a rocket engine that had to fire inside a larger rocket engine, without blowing up both. Seemed to be accepted.

    Quote
    It is generally assumed that Blue lost their powerpack set during development testing of the BE-4 start-up sequence, so similar to what Rocketdyne went thru with SSME.
    Anything big enough is like that.

    Now, you can't have infinite sets of hardware. And, you need to advance the development w/o creating a new surprise downwind.

    Likely the AF/ULA are sweating the indefinite closure to where they can convince themselves of a stable and growing future.  Breaths life into an otherwise demoralized AR-1 team.

    Good news for the BE-4 team - they're not at AJR. Good news for the AR-1 team - they can convince AJR to not force them to function as if they're at AJR ...

    (Good news for the Raptor team - they've got a working engine and they didn't have to go through what both AR1/BE4 teams are going through right now.)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: woods170 on 06/21/2017 08:55 PM

    (Good news for the Raptor team - they've got a working engine and they didn't have to go through what both AR1/BE4 teams are going through right now.)
    Not quite. From what I hear from sources is that SpaceX lost Raptor components on several occassions during components testing at Stennis. Lost as in wrecked beyond repair. Not as spectacular as Blue's powerpack loss, but still...

    But I agree that SpaceX did not experience the politics surrounding Blue's BE-4 and Aerojet's AR-1.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: edkyle99 on 06/21/2017 11:53 PM
    Not as spectacular as Blue's powerpack loss, but still...
    Was it spectacular? 

    The thing about the BE-4 powerpack failure and the subsequent reporting of the failure is that  Blue hasn't released images or video, so those outside the company can only conjure images of a massive, earth-shaking, program-ending explosion in their heads.  If the company showed the failure, the reporting might be more realistic about what the failure means.

    If failure is supposed to be a *good* thing in this business, then come on Blue, celebrate the failure!  (SpaceX and Aerojet too.)

     - Ed Kyle
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 06/22/2017 12:43 AM
    Not as spectacular as Blue's powerpack loss, but still...
    Was it spectacular?
    High mass flows of high pressure, highly reactive hot gasses ... usually go up like massive fireworks.

    Quote
    The thing about the BE-4 powerpack failure and the subsequent reporting of the failure is that  Blue hasn't released images or video, so those outside the company can only conjure images of a massive, earth-shaking, program-ending explosion in their heads.  If the company showed the failure, the reporting might be more realistic about what the failure means.
    Might help.

    But ... be advised, in this bat$hit crazy, political environment, with govt dollars at stake, ... there's a lot of ways it can go wrong / be used inappropriately.  (Fairly recently saw SX coverage of regular static fires and tests being characterized by news outlets as "failed launches".)

    Can fault Bezos /BO for a lot of other things not being transparent. But remembering what happened with the SSME failures broadcast on the evening TV news in the 70's, no, don't blame any vendor for not showing such.

    Even if you do show video, it didn't help much sort things out with the AJ26 test stand failure, for OA and AJR.

    Ed, suggest a counterproposal to serve the need you're addressing.  That they let us know when things have gotten better, in passing minor milestones, and possibly letting us know what they've conquered.

    This "celebrate your victories" approach puts it as a "hero's struggle" (or journey), and is in keeping with some of the best that all of them have done.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: woods170 on 06/22/2017 06:57 AM
    Not as spectacular as Blue's powerpack loss, but still...
    Was it spectacular? 

    The thing about the BE-4 powerpack failure and the subsequent reporting of the failure is that  Blue hasn't released images or video,
    Failure of an entire powerpack is generally more spectacular in nature than failure of a component such as a preburner.
    And no, I'm not claiming the powerpack blew up. It just simply could have ruptured or sheared or desintegrated or have a burn-through, etc. etc.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: guckyfan on 06/22/2017 07:36 AM
    Component test failures, especially when testing early oxygen rich preburners and turbopump components are to be expected until they get their material properties right. No doubt both SpaceX and BO had them.

    A full powerhead test failure is somewhat more significant. Especially when it happens at a time they have a full engine ready to test fire and have to delay that test. Which indicates it was not a failure they incured while testing at or beyond the limits of operation.

    Let's wait and see when they will have a full engine test firing at least of several seconds.

    It is still a failure during test. It does not indicate BO will not get there. But it is a delay at an unconvenient time. Mostly for ULA.

    Title: Re: Blue Origin's BE-4 Engine
    Post by: TrevorMonty on 06/22/2017 10:43 AM
    Blue have spare engines and test stand. Any delay will be from finding out extactly what went wrong..Then any mods to next engine.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: guckyfan on 06/22/2017 02:30 PM
    Blue have spare engines and test stand. Any delay will be from finding out extactly what went wrong..Then any mods to next engine.

    That's what I said. They don't even need a spare engine, they have never fired the first one. They stumbled over something unexpected and do not continue their test program for the time being.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Lar on 06/22/2017 04:17 PM
    Not as spectacular as Blue's powerpack loss, but still...
    Was it spectacular? 

    The thing about the BE-4 powerpack failure and the subsequent reporting of the failure is that  Blue hasn't released images or video, so those outside the company can only conjure images of a massive, earth-shaking, program-ending explosion in their heads.  If the company showed the failure, the reporting might be more realistic about what the failure means.

    If failure is supposed to be a *good* thing in this business, then come on Blue, celebrate the failure!  (SpaceX and Aerojet too.)

    Ed, we fans understand that not every explosion is a disaster. But the media doesn't. The general public do not, either. Fix that first.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: JasonAW3 on 06/22/2017 04:33 PM
    In this business, you HAVE to expect some things to fail and sometimes go boom.

          That's just the nature of working with brand new designs and highly volatile cryogenic liquids.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Chasm on 06/22/2017 05:57 PM
    What I find interesting is that -according to the talks- Blue did heaps of tests up to the 400klbf level. Delivery of the complete engine and ramping tests up to 550klbf were roughly at the same time. Then we got news that a powerpack failed.

    If that timeline is right the delays ans problems seem to be more about issue(s) with the uprating than anything else. Why else test preburners during all of 2016 at 400klbf max if you need 550 asap?

    Kremlinology. :-\
    I do hope that both Blue ans SpaceX take lots of video and interviews during the development. Then, a few years down the road, produce nice documentations so that we can find out what actually happened.  8)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Req on 06/25/2017 08:08 AM
    I'm a little late to the party, but having just caught up on this thread, I want to weigh in.

    To me, it seems like all of the points that people have been making about how this anomaly is expected/normal/etc and falls into the "neutral" instead of the "bad" category can be condensed down to one linchpin - was this possibility baked into the schedule margins for the RD-180 replacement contract(s) or not?

    If this is to be characterized as nominal/predictable, then it follows that there should be no impact on schedule, because it was anticipated, and built into the schedule margin for the contracts.

    I don't know if this will impact the schedule or not, but it sounds like the major players are worried that it will.  As always, time will tell.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: woods170 on 06/25/2017 11:02 AM
    I'm a little late to the party, but having just caught up on this thread, I want to weigh in.

    To me, it seems like all of the points that people have been making about how this anomaly is expected/normal/etc and falls into the "neutral" instead of the "bad" category can be condensed down to one linchpin - was this possibility baked into the schedule margins for the RD-180 replacement contract(s) or not?

    If this is to be characterized as nominal/predictable, then it follows that there should be no impact on schedule, because it was anticipated, and built into the schedule margin for the contracts.

    I don't know if this will impact the schedule or not, but it sounds like the major players are worried that it will.  As always, time will tell.
    Most rocket engine manufacturers will never publically admit that they did not put sufficient margin into the development schedule to alleviate development trouble (such as a failure on the test-stand). Publically stated schedules for readiness of a new engine are almost always too optimistic. Blue and SpaceX are no exceptions.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Req on 06/25/2017 11:22 AM
    I'm a little late to the party, but having just caught up on this thread, I want to weigh in.

    To me, it seems like all of the points that people have been making about how this anomaly is expected/normal/etc and falls into the "neutral" instead of the "bad" category can be condensed down to one linchpin - was this possibility baked into the schedule margins for the RD-180 replacement contract(s) or not?

    If this is to be characterized as nominal/predictable, then it follows that there should be no impact on schedule, because it was anticipated, and built into the schedule margin for the contracts.

    I don't know if this will impact the schedule or not, but it sounds like the major players are worried that it will.  As always, time will tell.
    Most rocket engine manufacturers will never publically admit that they did not put sufficient margin into the development schedule to alleviate development trouble (such as a failure on the test-stand). Publically stated schedules for readiness of a new engine are almost always too optimistic. Blue and SpaceX are no exceptions.

    I don't agree with the assertion that Blue and SpaceX intentionally fabricate schedules and enter into fixed-price contracts knowing full well that it is not realistic to deliver.  I suspect that it's not even possible given the amount of oversight that both companies currently have with NASA/USAF.  The suggestion seems absurd to me, especially absent the typical cost+ structure.

    My main point is that there's a catch-22 here - if it's so easy for the posters on this forum to characterize as a normal part of engine development, then how did the experts miss it?  I reject the notion that they intentionally ignored it.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Jim on 06/25/2017 05:19 PM
    Spacex and Blue do not have any development contracts with the US govt.  They are doing this work on their own dime and their own schedules.   Blue has no Air Force or NASA oversight.  Spacex has no NASA oversight either.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Confusador on 06/25/2017 10:22 PM
    I'm a little late to the party, but having just caught up on this thread, I want to weigh in.

    To me, it seems like all of the points that people have been making about how this anomaly is expected/normal/etc and falls into the "neutral" instead of the "bad" category can be condensed down to one linchpin - was this possibility baked into the schedule margins for the RD-180 replacement contract(s) or not?

    If this is to be characterized as nominal/predictable, then it follows that there should be no impact on schedule, because it was anticipated, and built into the schedule margin for the contracts.

    I don't know if this will impact the schedule or not, but it sounds like the major players are worried that it will.  As always, time will tell.
    Most rocket engine manufacturers will never publically admit that they did not put sufficient margin into the development schedule to alleviate development trouble (such as a failure on the test-stand). Publically stated schedules for readiness of a new engine are almost always too optimistic. Blue and SpaceX are no exceptions.

    I don't agree with the assertion that Blue and SpaceX intentionally fabricate schedules and enter into fixed-price contracts knowing full well that it is not realistic to deliver.  I suspect that it's not even possible given the amount of oversight that both companies currently have with NASA/USAF.  The suggestion seems absurd to me, especially absent the typical cost+ structure.

    My main point is that there's a catch-22 here - if it's so easy for the posters on this forum to characterize as a normal part of engine development, then how did the experts miss it?  I reject the notion that they intentionally ignored it.

    Knowing that you are going to have some problems that will result in some delays doesn't mean you can accurately predict those delays.  If you knew what was going to fail, you wouldn't do it!  So you put down the nominal values that you *can* predict, and everyone involved knows to apply a margin of error based on their own confidence.  I would describe that as "left as an exercise for the reader", not "intentionally ignored".  Not sure why you think it malicious.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: woods170 on 06/26/2017 06:37 AM
    Most rocket engine manufacturers will never publically admit that they did not put sufficient margin into the development schedule to alleviate development trouble (such as a failure on the test-stand). Publically stated schedules for readiness of a new engine are almost always too optimistic. Blue and SpaceX are no exceptions.

    I don't agree with the assertion that Blue and SpaceX intentionally fabricate schedules and enter into fixed-price contracts knowing full well that it is not realistic to deliver.  I suspect that it's not even possible given the amount of oversight that both companies currently have with NASA/USAF.  The suggestion seems absurd to me, especially absent the typical cost+ structure.

    My main point is that there's a catch-22 here - if it's so easy for the posters on this forum to characterize as a normal part of engine development, then how did the experts miss it?  I reject the notion that they intentionally ignored it.

    SpaceX and Blue do in fact intentionally establish schedules. In doing so they very closely look at what needs to be done, how that will be done and possibly when it will be done. They also throw in margin, usually based on a best-practices prediction of what to expect. That even includes margin to deal with failures. But, development trouble, and associated failures, often comes from unexpected places and the magnitude of impact is usually utterly unpredictable.

    So, and that was my point, despite all the care going into establishing a schedule it is still more of a rule than an exception that the schedule slips due to the occurence of known-unknows and unknown-unknowns. Particularly the latter type has a tendency to bite a schedule in the *ss.

    Just have a look at the last 4 decades: when was the last time a major development undertaking in spaceflight actually met it's original schedule?

    So yeah, given prior experience in the past 4 to 5 decades it is very safe to state that almost every publically stated develoment schedule will eventually NOT hold. That is why terms like "as soon as" or "no earlier then" are standard ingredients of public schedule statements.

    About oversight by NASA and USAF: what Jim said.
    Additionally, USAF pays for subsidizes part of the development of Raptor. However, that does not give them oversight over development of Raptor. At most it gives them insight which is a different thing.
    With regards to BE-4: the development arrangement between Blue and ULA for BE-4 on Vulcan is a private arrangement. USAF will probably have some level on insight via their arrangements with ULA, but most decidedly not oversight.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Req on 06/26/2017 01:50 PM
    I don't disagree with any of the above points and corrections, but I still very much feel that there is a schedule(downselection for example), as evidenced by the concern that they may not meet said schedule and the sentiment that such would potentially be a boon for AR.

    As such, I still feel that my point has some merit - if it's so easy for the posters on this forum to characterize as a normal part of engine development, then it should be baked into said schedule and there should be no impact.  Beyond that, nobody should be expressing concern over schedule in an official capacity and we shouldn't be discussing how this may impact the selection date or the fate of AR.  The only thing I'm disputing here is the 20/20 highsight characterization, in the event that the program does actually come in behind schedule as a result.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: woods170 on 06/26/2017 06:54 PM
    As such, I still feel that my point has some merit - if it's so easy for the posters on this forum to characterize as a normal part of engine development, then it should be baked into said schedule and there should be no impact. 

    Again: yes, development trouble can be expected. But the nature of that development trouble, and thus the impact it has on schedule is almost pure guesswork. If one knew in advance what would go wrong, one would avoid it, and thus it would not go wrong.
    The mere fact that things go wrong during development is testament to the fact that one does not know in advance what will go wrong.
    So no, contrary to what you think it is NOT possible to bake every possible problem into the schedule. There is no 20/20 hindsight. It's a fact of life that these development schedules are always too optimistic, simply because seeing into the future is not possible.
    Never heard of Murphy, have you?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Jim on 06/26/2017 07:40 PM
    As such, I still feel that my point has some merit - if it's so easy for the posters on this forum to characterize as a normal part of engine development, then it should be baked into said schedule and there should be no impact. 


    No, you create success based schedules and state it as so upfront.  There is no way "bake" in delays.  Where do you put the delays, in production, component testing, engine test runs, test stand build?

    The schedule is built as though things will work, otherwise there will be a work stoppage while waiting for other parts to catch up while burning through the baked in delay.  The only place that a delay can be placed is at the end.  "We intend to be complete by X but we may have problems and X+Y weeks is more likely"
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 06/26/2017 07:59 PM
    Likely the BE-4 simulations and prior powerpack tests were used to convince the AF that working through start-up would not have issues.

    Then they had an issue.

    Likely the AF looked at all the collateral, asked pointed questions, and came to the conclusions that the situation was far from closed, so being open they needed to respond to the threat by reviving a program.

    Both decisions are reasonable. BE4 is considerably further ahead, and the publicly shared sim result certainly helped to justify that first decision. The second makes sense also if an "impossible" pressure ramp or other not to be found in the earlier sims occurs, which is not an uncommon thing.

    These things go into a free fall for an indeterminate time - which is the risk. Also, there's nothing to insure that AR-1 won't also have the same, or for that matter any LRE of this scale/development phase.

    Nature of the beast.

    The schedule is built as though things will work, otherwise there will be a work stoppage while waiting for other parts to catch up while burning through the baked in delay.
    Agreed. Where do you "bake in" the "unexpected"?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Kabloona on 06/26/2017 08:25 PM
    Quote
    Likely the AF looked at all the collateral, asked pointed questions, and came to the conclusions that the situation was far from closed, so being open they needed to respond to the threat by reviving a program.

    Reviving which program? AR-1? Hasn't that been running in parallel to BE-4 all along?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: LouScheffer on 06/26/2017 08:43 PM
    As such, I still feel that my point has some merit - if it's so easy for the posters on this forum to characterize as a normal part of engine development, then it should be baked into said schedule and there should be no impact. 
    Competition makes it very hard to set a conservative schedule, including unexpected delays, unless all sides are somehow compelled to be equally honest.

    For example, suppose BO is completely forthcoming and says "Realistically, we expect 2 years of unanticipated problems", so we'll promise delivery in 2021.   But this opens them up to AR saying "Our schedule calls for us to be ready in 2019", and getting the order, even though they are currently behind in development, and may well have just as many unanticipated delays.   And if estimating the time for "unknown unknowns" is hard, it's even harder to compare the right magnitude of "unknown unknowns" to be applied by two different vendors.  So people quote the "no problems" engineering time, knowing that's a proxy for the real development time, which is unknown. 

    Note that this optimism is not used when there is a real, hard deadline, such as a planetary launch window.  In this case managers typically leave many months of schedule reserve, precisely to allow for unanticipated problems.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 06/26/2017 09:06 PM
    Quote
    Likely the AF looked at all the collateral, asked pointed questions, and came to the conclusions that the situation was far from closed, so being open they needed to respond to the threat by reviving a program.

    Reviving which program? AR-1? Hasn't that been running in parallel to BE-4 all along?
    AR-1. Apparently not.

    (Mind you, you can "adjust" the rate on a program by accelerating/decelerating it with the money spigot. Doesn't have to be "full stop".)

    There are certain expensive phases of LRE development, like materials test at scale, and full scale component integration, where your commitment to "go ahead" brings with it substantial "drawn down" penalties.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Kabloona on 06/26/2017 10:07 PM
    Quote
    Likely the AF looked at all the collateral, asked pointed questions, and came to the conclusions that the situation was far from closed, so being open they needed to respond to the threat by reviving a program.

    Reviving which program? AR-1? Hasn't that been running in parallel to BE-4 all along?
    AR-1. Apparently not.

    What did I miss? I thought Aerojet had been running hard to catch up to BE-4 all this time.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: RedLineTrain on 06/26/2017 10:24 PM
    Quote
    Likely the AF looked at all the collateral, asked pointed questions, and came to the conclusions that the situation was far from closed, so being open they needed to respond to the threat by reviving a program.

    Reviving which program? AR-1? Hasn't that been running in parallel to BE-4 all along?
    AR-1. Apparently not.

    What did I miss? I thought Aerojet had been running hard to catch up to BE-4 all this time.

    I was skeptical too.  Aviation Week reporting...

    Oh dear.  You're linking to Loren Thompson?  Not an authoritative source, by any means.
    Here's another source with a similar report.
    http://aviationweek.com/space/usaf-keep-ar-1-work-going-amid-be-4-setback

     - Ed Kyle
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Kabloona on 06/26/2017 10:33 PM
    Quote
    Likely the AF looked at all the collateral, asked pointed questions, and came to the conclusions that the situation was far from closed, so being open they needed to respond to the threat by reviving a program.

    Reviving which program? AR-1? Hasn't that been running in parallel to BE-4 all along?
    AR-1. Apparently not.

    What did I miss? I thought Aerojet had been running hard to catch up to BE-4 all this time.

    I was skeptical too.  Aviation Week reporting...

    Oh dear.  You're linking to Loren Thompson?  Not an authoritative source, by any means.
    Here's another source with a similar report.
    http://aviationweek.com/space/usaf-keep-ar-1-work-going-amid-be-4-setback

     - Ed Kyle

    Thanks for that link. I can't see the entire article, but the photo caption says the plan had been to stop AR1 development  at CDR, which I hadn't heard, but now they will continue past CDR given the BE-4 hiccup. So that is the "revival" Space Ghost referred to. Got it.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Navier–Stokes on 06/28/2017 01:11 AM
    New article from Jeff Foust of SpaceNews:
    Blue Origin retains engine lead as House considers limitations on launch system funding (http://spacenews.com/blue-origin-retains-engine-lead-as-house-considers-limitations-on-launch-system-funding/)
    Quote
    [A]t a briefing of staff members organized by the House Armed Services Committee June 23, an independent assessment prepared by NASA’s Marshall Space Flight Center reportedly confirmed that BE-4 maintained a major schedule advantage over the AR1 despite the testing setback.

    “They are two years behind Blue Origin,” one meeting attendee, not authorized to speak on the record, said of the assessment’s conclusion about AR1. Another year would be needed to integrate the engine with a launch vehicle.

    The BE-4 powerpack testing mishap raised a number of questions by those at the briefing, the source said, but the NASA assessment concluded it would not have a major effect on the overall testing program for the engine. “They should be on track to restart testing in late summer and still stay on schedule,” the attendee recalled.

    That confidence is based on the hardware-rich testing approach the company has promoted. The briefing attendee noted the NASA assessment’s concerns about the AR1 were focused on its schedule and cost, rather than its technical development.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: edkyle99 on 06/28/2017 01:46 AM
    Yet another attempt to restrict Air Force funding to the the development of first-stage rocket engines only:
    http://spacenews.com/blue-origin-retains-engine-lead-as-house-considers-limitations-on-launch-system-funding/
    "“They should be on track to restart testing in late summer ... "

    Four months or more then.  Yikes.

     - Ed Kyle
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 06/28/2017 01:52 AM
    Yet another attempt to restrict Air Force funding to the the development of first-stage rocket engines only:
    http://spacenews.com/blue-origin-retains-engine-lead-as-house-considers-limitations-on-launch-system-funding/
    "“They should be on track to restart testing in late summer ... "

    Four months or more then.  Yikes.

     - Ed Kyle
    I believe I did say "fireworks" ...  ::)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Coastal Ron on 06/28/2017 01:59 AM
    Yet another attempt to restrict Air Force funding to the the development of first-stage rocket engines only:
    http://spacenews.com/blue-origin-retains-engine-lead-as-house-considers-limitations-on-launch-system-funding/
    "“They should be on track to restart testing in late summer ... "

    Four months or more then.  Yikes.

    Here in the Northern Hemisphere we start summer around June 21st, and it is followed by autumn, which starts around the 21st of September, so at most "late summer" is 3 months out, but could be as little as 2 months away.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: edkyle99 on 06/28/2017 02:06 AM
    Yet another attempt to restrict Air Force funding to the the development of first-stage rocket engines only:
    http://spacenews.com/blue-origin-retains-engine-lead-as-house-considers-limitations-on-launch-system-funding/
    "“They should be on track to restart testing in late summer ... "

    Four months or more then.  Yikes.

    Here in the Northern Hemisphere we start summer around June 21st, and it is followed by autumn, which starts around the 21st, so at most "late summer" is 3 months out, but could be as little as 2 months away.
    I was thinking four months from the date of the incident.  One month has already passed since then.  :)

     - Ed Kyle
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 06/28/2017 02:19 AM
    New article from Jeff Foust of SpaceNews:

     (http://spacenews.com/blue-origin-retains-engine-lead-as-house-considers-limitations-on-launch-system-funding/)
    You missed this part:
    Quote
    The section includes a specific prohibition against funding “the development of new launch vehicles under such program.” It also specifically defines a “rocket propulsion system” that can be funded as a first-stage rocket engine or motor. “The term does not include a launch vehicle, an upper stage, a strap-on motor, or related infrastructure,” it states.

    Such language would allow the Air Force to continue funding development of Aerojet Rocketdyne’s AR1 engine. However, it could restrict funding to United Launch Alliance to support development of its Vulcan rocket, as that work goes beyond development of a first-stage engine.

    This complicates things in congressional micromanaging of EELV options. It attempts to narrow the scope of how EELV could be funded to eliminate the foreign engine dependency.

    So alternatives and advanced work could not be attempted. Vulcan and ACES.

    And, it creates a legal contradiction over "upper stage engines". Technically, Raptor as funded was an upper stage engine, however it can be used as a booster engine, and it is a current engine under development.

    It is also at a more advanced state than AR-1 (which these proposed restrictions are aimed primarily to benefit) and BE-4. That already addresses/creates a potential vendor bias in law, of which a large body of procurement related law, administrative practice and process stands in conflict with.

    The problem with meddling is that it only serves to "monkey wrench" things further. And then you have to undo it.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 06/28/2017 02:23 AM
    Yet another attempt to restrict Air Force funding to the the development of first-stage rocket engines only:
    http://spacenews.com/blue-origin-retains-engine-lead-as-house-considers-limitations-on-launch-system-funding/
    "“They should be on track to restart testing in late summer ... "

    Four months or more then.  Yikes.

    Here in the Northern Hemisphere we start summer around June 21st, and it is followed by autumn, which starts around the 21st, so at most "late summer" is 3 months out, but could be as little as 2 months away.
    I was thinking four months from the date of the incident.  One month has already passed since then.  :)

     - Ed Kyle

    If it was a leak or a cold flow fracture, it would have been up with a new hardware set by now. Big boom. Rebuild level boom. Like AJ26's fun on E1 test stand.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: LouScheffer on 06/28/2017 03:36 AM
    "“They should be on track to restart testing in late summer ... "

    Four months or more then.  Yikes.
    Here in the Northern Hemisphere we start summer around June 21st, and it is followed by autumn, which starts around the 21st, so at most "late summer" is 3 months out, but could be as little as 2 months away.
    I was thinking four months from the date of the incident.  One month has already passed since then.  :)
    If it was a leak or a cold flow fracture, it would have been up with a new hardware set by now. Big boom. Rebuild level boom. Like AJ26's fun on E1 test stand.
    We know they have multiple engines, and I thought they had multiple test stands.  But if so, presumably they would continue testing (at the 400K lbf level, at least) while they investigate why it failed at 550K lbf and repair/replace the busted stand.    So it would seem they only have one test stand.

    Also, suppose they need to modify some fairly fundamental part, such as the turbopump, to run safely at 550K lbf.  How quickly can something like this be turned around?  They need to re-design the part(s) (which might need CFD work), then re-prototype it, then component test it, then re-integrate it, then re-burp test it, etc. until they can get back to testing the engine.   I could easily imagine this taking a few months, in parallel with test stand repair.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Semmel on 06/28/2017 09:08 AM
    This complicates things in congressional micromanaging of EELV options. It attempts to narrow the scope of how EELV could be funded to eliminate the foreign engine dependency.

    So alternatives and advanced work could not be attempted. Vulcan and ACES.

    And, it creates a legal contradiction over "upper stage engines". Technically, Raptor as funded was an upper stage engine, however it can be used as a booster engine, and it is a current engine under development.

    It is also at a more advanced state than AR-1 (which these proposed restrictions are aimed primarily to benefit) and BE-4. That already addresses/creates a potential vendor bias in law, of which a large body of procurement related law, administrative practice and process stands in conflict with.

    The problem with meddling is that it only serves to "monkey wrench" things further. And then you have to undo it.

    Two views:
    1. ULA should fund the development of Vulcan out of its own pocket, just as other US rocket manufacturers do as well. So it should have no impact on the choice between AR1 and BE4. Nor should it have any impact on the development of ACES. ULA has enough revenue. Its not the fault of DOD that they give it all to its parents to the extend that nothing is left for R&D. So in this case, the DOD wants to get rid of the RD180, this bill fits to gain that goal.
    2. The error in this thinking is, that its almost impossible to exchange the thrust structure without developing a new launch vehicle. So the sensible thing should be to replace a launch vehicle that uses RD180 with a launch vehicle that does not. Independent of if this is an entirely new design or an old rocket replacing just the thrust structure. So in this view, DOD should put forwards the requirement of removing the RD180 but should keep out of the solution space on how that goal is achieved.

    I think both views are valid. And I dont read the indication within this bill that ULA has to use the AR1 over the BE4.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: LouScheffer on 06/28/2017 12:21 PM
    These comments were made in the Orbital/NG thread, but fit better here...
    "“They should be on track to restart testing in late summer ... "

    Four months or more then.  Yikes.
    Here in the Northern Hemisphere we start summer around June 21st, and it is followed by autumn, which starts around the 21st, so at most "late summer" is 3 months out, but could be as little as 2 months away.
    I was thinking four months from the date of the incident.  One month has already passed since then.  :)
    If it was a leak or a cold flow fracture, it would have been up with a new hardware set by now. Big boom. Rebuild level boom. Like AJ26's fun on E1 test stand.
    We know they have multiple engines, and I thought they had multiple test stands.  But if so, presumably they would continue testing (at the 400K lbf level, at least) while they investigate why it failed at 550K lbf and repair/replace the busted stand.    So it would seem they only have one test stand.

    Also, suppose they need to modify some fairly fundamental part, such as the turbopump, to run safely at 550K lbf.  How quickly can something like this be turned around?  They need to re-design the part(s) (which might need CFD work), then re-prototype it, then component test it, then re-integrate it, then re-burp test it, etc. until they can get back to testing the engine.   I could easily imagine this taking a few months, in parallel with test stand repair.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: meberbs on 06/28/2017 02:19 PM
    New article from Jeff Foust of SpaceNews:
    Blue Origin retains engine lead as House considers limitations on launch system funding (http://spacenews.com/blue-origin-retains-engine-lead-as-house-considers-limitations-on-launch-system-funding/)

    Quote
    The company said it will make a $200 million investment to develop the facility, capable of producing up to 30 BE-4 engines per year.
    I hadn't noticed the engine production rate in other reporting. Does 30/year seem too low to anyone else? Do we know how many they can make in Kent if they also keep production there?

    Even with perfect and unlimited reuse, 12/year 2nd stages expended on New Glenn would only allow 9 Vulcans per year until ULA starts their reuse program. If one new New Glenn is built each year as well, that knocks it down to 5-6 Vulcans per year.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: TrevorMonty on 06/28/2017 03:01 PM
    New article from Jeff Foust of SpaceNews:
    Blue Origin retains engine lead as House considers limitations on launch system funding (http://spacenews.com/blue-origin-retains-engine-lead-as-house-considers-limitations-on-launch-system-funding/)

    Quote
    The company said it will make a $200 million investment to develop the facility, capable of producing up to 30 BE-4 engines per year.
    I hadn't noticed the engine production rate in other reporting. Does 30/year seem too low to anyone else? Do we know how many they can make in Kent if they also keep production there?

    Even with perfect and unlimited reuse, 12/year 2nd stages expended on New Glenn would only allow 9 Vulcans per year until ULA starts their reuse program. If one new New Glenn is built each year as well, that knocks it down to 5-6 Vulcans per year.
    Kent factory could add another few a year.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Darkseraph on 06/28/2017 03:26 PM
    Delta 4 and Atlas V launch vehicles will almost certainly be flying in the early 2020s so they probably won't be flying too many Vulcan Rockets early on. Blue Origin are probably not going to be flying New Glenn 12 times a year initially either. Blue have some capacity to build engines at their Washington facility already. They have hinted their interest in later reusing their second stages, which will further curb demand for new engines. When demand picks up for more BE-3s and BE4's, there's little doubt they won't just add more capacity when it's needed.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: FutureSpaceTourist on 06/28/2017 03:59 PM
    George Sowers has just commented on this:

    Quote
    George Sowers‏ @george_sowers 20m20 minutes ago

    George Sowers Retweeted Jeff Foust

    Parasite (AR) killing the host (ULA)...

    https://twitter.com/george_sowers/status/880087678733217792 (https://twitter.com/george_sowers/status/880087678733217792)

    Ouch ... !

    New article from Jeff Foust of SpaceNews:
    Blue Origin retains engine lead as House considers limitations on launch system funding (http://spacenews.com/blue-origin-retains-engine-lead-as-house-considers-limitations-on-launch-system-funding/)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 06/28/2017 09:27 PM
    Quote from: George Sowers
    Parasite (AR) killing the host (ULA)...

    https://twitter.com/george_sowers/status/880087678733217792 (https://twitter.com/george_sowers/status/880087678733217792)
    Ouch ... !

    The advantages of being retired is that you can speak your mind.

    And, being distinguished former ULA executive - it doesn't come across as a criticism of ULA, unlike anyone else.

    Truer words have never been spoken.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Semmel on 06/29/2017 07:22 AM
    Quote from: George Sowers
    Parasite (AR) killing the host (ULA)...

    https://twitter.com/george_sowers/status/880087678733217792 (https://twitter.com/george_sowers/status/880087678733217792)
    Ouch ... !

    The advantages of being retired is that you can speak your mind.

    And, being distinguished former ULA executive - it doesn't come across as a criticism of ULA, unlike anyone else.

    Truer words have never been spoken.

    Sorry to be so stupid but I still dont get it. Why does ULA depend on DOD for developing new launch vehicles? Within the new bill, DOD is allowed to pay for the ULA share of development costs of BE4. ULA would still be able to fund the development of Vulcan from its own profits. I must be missing something because every expert seems to see it differently. What am I missing?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: gongora on 06/29/2017 02:50 PM
    Quote from: George Sowers
    Parasite (AR) killing the host (ULA)...

    https://twitter.com/george_sowers/status/880087678733217792 (https://twitter.com/george_sowers/status/880087678733217792)
    Ouch ... !

    The advantages of being retired is that you can speak your mind.

    And, being distinguished former ULA executive - it doesn't come across as a criticism of ULA, unlike anyone else.

    Truer words have never been spoken.

    Sorry to be so stupid but I still dont get it. Why does ULA depend on DOD for developing new launch vehicles? Within the new bill, DOD is allowed to pay for the ULA share of development costs of BE4. ULA would still be able to fund the development of Vulcan from its own profits. I must be missing something because every expert seems to see it differently. What am I missing?

    The big defense contractors aren't used to spending their own money to develop a product for the government.  Especially when there was already a proposed plan in place where the government would pay for most of the development.  Why hurry to spend hundreds of millions from your own pocket when it looks likely the government will pay a majority of the cost if you just wait a little while?  ULA's main customer is the U.S. government, commercial launches are just a little side business, and that isn't likely to change with multiple new launchers hitting the market around the same time as Vulcan.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: AncientU on 06/29/2017 04:47 PM
    BE is getting a leg up to match AR's political pull:
    Quote
    Sen. Shelby is clearly on Team Blue Origin now. Asks Robert Lightfoot for a copy of report that found BE-4 engine ahead of Aerojet's AR1.

    https://twitter.com/SciGuySpace/status/880432831272497153

    Apparently doesn't take much to buy a congressional delegation these days.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Kabloona on 06/29/2017 05:05 PM
    BE is getting a leg up to match AR's political pull:
    Quote
    Sen. Shelby is clearly on Team Blue Origin now. Asks Robert Lightfoot for a copy of report that found BE-4 engine ahead of Aerojet's AR1.

    https://twitter.com/SciGuySpace/status/880432831272497153

    Apparently doesn't take much to buy a congressional delegation these days.

    I'm not defending designed-by-politics rockets, but at least Sen Shelby is seeing the light and (apparently) changing horses from a loser (AR1) to a (probable) winner BE-4.

    Sometimes politicians arrive at the right answer, despite the meandering path.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: gospacex on 06/29/2017 05:16 PM
    Quote from: George Sowers
    Parasite (AR) killing the host (ULA)...

    https://twitter.com/george_sowers/status/880087678733217792 (https://twitter.com/george_sowers/status/880087678733217792)
    Ouch ... !

    The advantages of being retired is that you can speak your mind.

    And, being distinguished former ULA executive - it doesn't come across as a criticism of ULA, unlike anyone else.

    Truer words have never been spoken.

    Sorry to be so stupid but I still dont get it. Why does ULA depend on DOD for developing new launch vehicles? Within the new bill, DOD is allowed to pay for the ULA share of development costs of BE4. ULA would still be able to fund the development of Vulcan from its own profits. I must be missing something because every expert seems to see it differently. What am I missing?

    The big defense contractors aren't used to spending their own money to develop a product for the government.  Especially when there was already a proposed plan in place where the government would pay for most of the development.  Why hurry to spend hundreds of millions from your own pocket when it looks likely the government will pay a majority of the cost if you just wait a little while?

    I don't imagine SpaceX will be okay with government funding its competitor, especially on top of ELC still in force.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: woods170 on 06/29/2017 05:51 PM
    Quote from: George Sowers
    Parasite (AR) killing the host (ULA)...

    https://twitter.com/george_sowers/status/880087678733217792 (https://twitter.com/george_sowers/status/880087678733217792)
    Ouch ... !

    The advantages of being retired is that you can speak your mind.

    And, being distinguished former ULA executive - it doesn't come across as a criticism of ULA, unlike anyone else.

    Truer words have never been spoken.

    Sorry to be so stupid but I still dont get it. Why does ULA depend on DOD for developing new launch vehicles? Within the new bill, DOD is allowed to pay for the ULA share of development costs of BE4. ULA would still be able to fund the development of Vulcan from its own profits. I must be missing something because every expert seems to see it differently. What am I missing?

    The big defense contractors aren't used to spending their own money to develop a product for the government.  Especially when there was already a proposed plan in place where the government would pay for most of the development.  Why hurry to spend hundreds of millions from your own pocket when it looks likely the government will pay a majority of the cost if you just wait a little while?

    I don't imagine SpaceX will be okay with government funding its competitor, especially on top of ELC still in force.
    The government is co-funding Raptor.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: LouScheffer on 06/29/2017 06:04 PM

    I don't imagine SpaceX will be okay with government funding its competitor, especially on top of ELC still in force.
    Boeing raises holy h*ll whenever European governments give money to Airbus to design products that compete with Boeing, and insists that their large., lucrative military contracts are not relevant to, and certainly do not subsidize, their commercial airplane business.

    So to be consistent, Boeing should argue that the government should not fund Vulcan development, and that the large government contract to SpaceX are irrelevant in this context.

    I'm not expecting consistency here.....
    Title: Re: Blue Origin's BE-4 Engine
    Post by: gospacex on 06/29/2017 06:05 PM
    I don't imagine SpaceX will be okay with government funding its competitor, especially on top of ELC still in force.

    The government is co-funding Raptor.

    I'm talking about Vulcan development, not BE-4.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: rayleighscatter on 06/29/2017 09:03 PM

    The big defense contractors aren't used to spending their own money to develop a product for the government.
    This really isn't true. Government procurement is far too competitive and if a contractor doesn't come into a bid without significant existing background in the product they are proposing then they have no real chance of winning a bid.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Jim on 06/29/2017 09:13 PM
    I don't imagine SpaceX will be okay with government funding its competitor, especially on top of ELC still in force.

    The government is co-funding Raptor.

    I'm talking about Vulcan development, not BE-4.

    Do we have to go over this again.
    a.  The gov't is not funding Vulcan
    b.  Spacex got money from the gov't for F9 and Dragon development under COTS.
    c.  Even though the Air Force gave Boeing and Lockheed Martin $500 million apiece for Delta IV and Atlas V development, Boeing spent 2.5 Billion of their own and LM 1.5 Billion of their own.  And the Air Force got two families of medium vehicles and a heavy along with 3 launch pads that all could support all the DOD requirements including vertical integration and other payload interfaces.
    d.  ULA now get ELC because it needs to keep a west coast heavy pad available even though it launches less than once every two years.  ELC also pays for other DOD requirements.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Lars-J on 06/29/2017 09:14 PM

    The big defense contractors aren't used to spending their own money to develop a product for the government.
    This really isn't true. Government procurement is far too competitive and if a contractor doesn't come into a bid without significant existing background in the product they are proposing then they have no real chance of winning a bid.

    How is that a contradiction of what he wrote? What you say would be true (and force investment) if there was a large number of corporations left that competed for contracts. But that isn't the case anymore. Almost everyone has merged up or acquired each other, and they all have a 'background' in what they are bidding for.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Semmel on 06/30/2017 06:32 AM
    Do we have to go over this again.
    a.  The gov't is not funding Vulcan

    Why is the bill a problem then? Can you please explain that?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: woods170 on 06/30/2017 07:14 AM
    I don't imagine SpaceX will be okay with government funding its competitor, especially on top of ELC still in force.

    The government is co-funding Raptor.

    I'm talking about Vulcan development, not BE-4.
    The government is not funding Vulcan development. It is funding BE-4 development, via ULA. The 2016 award of funding for RD-180 replacements went (amongst others) to ULA. But ULA is using that funding to help finance development of BE-4, not Vulcan itself. Another award from the same rpf went to SpaceX for development of Raptor.

    So, USAF is in both cases funding the development of engines, not rockets. So there is nothing SpaceX would be upset about.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Tomness on 06/30/2017 03:53 PM
    Could SpaceX's Rapter Power Pack be used or lessons learned to mature Blue's BE-4 development?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: gospacex on 06/30/2017 03:58 PM
    I don't imagine SpaceX will be okay with government funding its competitor, especially on top of ELC still in force.

    The government is co-funding Raptor.

    I'm talking about Vulcan development, not BE-4.
    The government is not funding Vulcan development. It is funding BE-4 development, via ULA.

    The posts I responded to did in fact discuss that ULA is trying to get USG to fund Vulcan development as well, not only BE-4. I'm not pulling it out of thin air.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: gongora on 06/30/2017 03:59 PM
    Could SpaceX's Rapter Power Pack be used or lessons learned to mature Blue's BE-4 development?

    1.  They are not the same type of engine design (ORSC for BE-4, FFSC for Raptor).
    2.  Why would SpaceX turn their proprietary designs and test results over to a competitor?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: abaddon on 06/30/2017 04:27 PM
    First of all, no.

    Second, even if yes, why would SpaceX be interested in helping a competitor?

    Third, Blue is fully capable of figuring this out on their own, and are in fact the most expert of experts dealing with their own engine design.

    It's gonna be fine without outside help.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Lar on 06/30/2017 04:49 PM
    This isn't space policy, thanks. It's also not about SpaceX...
    Title: Re: Blue Origin's BE-4 Engine
    Post by: 99miles on 07/13/2017 05:42 PM
    Does anyone have any guesses about the burn time of the BE-4 (at 100% rated thrust)?  Will it be similar to 270 second burn time of the RD-180?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: brickmack on 07/13/2017 09:05 PM
    For Vulcan you mean? Its propellant mass is estimated at like 380 tons for the core stage. 2x BE-4s put out (at sea level), ~4800000 newtons thrust at ~311 seconds ISP.

    4800000 = 9.8 * 311 * flowRate

    FlowRate = 1.57 tons/second

    About 242 seconds, or just over 4 minutes (probably closer to 5 or 5.5 with throttling)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: FutureSpaceTourist on 07/13/2017 09:47 PM
    Quote
    Madison County Commission votes to do their part in Blue Origin agreement

    POSTED 5:24 PM, JULY 12, 2017, BY CAITLAN DALLAS, UPDATED AT 09:28PM, JULY 12, 2017

    Quote
    "This commission voted to authorize that we do site preparation, and that we also contributed a half a million dollars towards this incentive package,"

    http://whnt.com/2017/07/12/madison-county-commission-votes-to-do-their-part-in-blue-origin-agreement/ (http://whnt.com/2017/07/12/madison-county-commission-votes-to-do-their-part-in-blue-origin-agreement/)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: FutureSpaceTourist on 07/15/2017 05:43 PM
    Quote
    Huntsville Oks deal 'confident' Blue Origin plant is coming

    Updated on July 15, 2017 at 11:43 AM
    Posted on July 14, 2017 at 5:17 AM

    The Huntsville City Council unanimously approved a deal Thursday night to bring a $200 million Blue Origin rocket engine factory and up to 400 high-paying jobs to Cummings Research Park.

    That so-called Project Development Agreement depends on Blue Origin Alabama getting an engine production contract from United Launch Alliance. [...]

    http://www.al.com/news/huntsville/index.ssf/2017/07/huntsville_oks_deal_confident.html (http://www.al.com/news/huntsville/index.ssf/2017/07/huntsville_oks_deal_confident.html)

    The agreement with Blue Origin is attached.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: edkyle99 on 07/16/2017 01:10 AM
    On May 14, after the BE-4 powerpack failure on Blue's Texas test stand, the company tweeted that it would be "back into testing soon".  Two months have now passed.  Is there any evidence that testing of any kind has resumed?

     - Ed Kyle
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Robotbeat on 07/16/2017 04:12 PM
    On May 14, after the BE-4 powerpack failure on Blue's Texas test stand, the company tweeted that it would be "back into testing soon".  Two months have now passed.  Is there any evidence that testing of any kind has resumed?

     - Ed Kyle
    Gradatim, Ed, Gradatim.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: yokem55 on 07/16/2017 04:48 PM
    On May 14, after the BE-4 powerpack failure on Blue's Texas test stand, the company tweeted that it would be "back into testing soon".  Two months have now passed.  Is there any evidence that testing of any kind has resumed?

     - Ed Kyle
    Well, if it's a design problem, then the hardware rich approach will mean that there is a lot of hardware that's been made that can't be used and new hardware would have to be built to fix the issue and that will take time. If it's a sequencing or controller issue, then I would expect them to be testing again shortly.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: edkyle99 on 08/09/2017 03:41 AM
    Or, perhaps its more ... late fall now? How's it going in the Texas heat?
    Blue would be crowing if there had been any success, I think. 

     - Ed Kyle
    Title: Re: Blue Origin's BE-4 Engine
    Post by: HVM on 08/09/2017 07:59 AM
    Even if BE-4 is considered here as moderate in technical aspects (compared to Raptor), it's still an oxidizer-rich staged combustion engine. And Americans never built, -and used- one for orbital flight. Also this is from company which has never built orbital class engine before. So, some delays are expected.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: StvB on 08/09/2017 12:28 PM
    Even if BE-4 is considered here as moderate in technical aspects (compared to Raptor), it's still an oxidizer-rich staged combustion engine. And Americans never built, -and used- one for orbital flight. Also this is from company which has never built orbital class engine before. So, some delays are expected.

    The RD-180 and 181 (Both from NPOE) are used on American rockets currently flying (Atlas and Antares, respectively). Not sure how easily that experience translates to future use of the BE-4, though.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Jim on 08/09/2017 12:46 PM
    It doesn't
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Robotbeat on 08/09/2017 12:47 PM
    Even if BE-4 is considered here as moderate in technical aspects (compared to Raptor), it's still an oxidizer-rich staged combustion engine. And Americans never built, -and used- one for orbital flight. Also this is from company which has never built orbital class engine before. So, some delays are expected.
    Good point.

    I'm excited that we have bothe Blue Origin and SpaceX, both BE-4 and Raptor. Wonderful assets, both represent an improvement in the state of the art.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: StvB on 08/09/2017 01:02 PM
    It doesn't

    I figured as much.

    I'm excited that we have bothe Blue Origin and SpaceX, both BE-4 and Raptor. Wonderful assets, both represent an improvement in the state of the art.

    It's definitely exciting to take in and I really enjoy reading the investigative work of people here on NSF
    Title: Re: Blue Origin's BE-4 Engine
    Post by: HVM on 08/09/2017 06:42 PM
    ...
    The RD-180 and 181 (Both from NPOE) are used on American rockets currently flying (Atlas and Antares, respectively). Not sure how easily that experience translates to future use of the BE-4, though.

    -Russian engines. I think, even as ULA has boosted, that they have RD-180 blueprints, Russian still have the secret sauce for oxygen-rich tech (-cough; porcelain enamel coating*; cough -). And like Jim says Blue doesn't have access for those.

    *"Currently, the Russian-developed enamel coatings are a far more mature and proven technology. However, application of these special coatings and/or advanced materials to U.S. ORSC engine designs has not been fully proven, so a comprehensive risk reduction program will be required."

    -Liquid Rocket Hydrocarbon Booster Engines (LRHCBE’s) for Launch Vehicles – A Status Report
    Robert L. Sackheim  Aerospace Propulsion Consultant, Huntsville, Alabama


    Title: Re: Blue Origin's BE-4 Engine
    Post by: flyright on 08/09/2017 07:44 PM
    ...
    The RD-180 and 181 (Both from NPOE) are used on American rockets currently flying (Atlas and Antares, respectively). Not sure how easily that experience translates to future use of the BE-4, though.

    -Russian engines. I think, even as ULA has boosted, that they have RD-180 blueprints, Russian still have the secret sauce for oxygen-rich tech (-cough; porcelain enamel coating*; cough -). And like Jim says Blue doesn't have access for those.

    *"Currently, the Russian-developed enamel coatings are a far more mature and proven technology. However, application of these special coatings and/or advanced materials to U.S. ORSC engine designs has not been fully proven, so a comprehensive risk reduction program will be required."

    -Liquid Rocket Hydrocarbon Booster Engines (LRHCBE’s) for Launch Vehicles – A Status Report
    Robert L. Sackheim  Aerospace Propulsion Consultant, Huntsville, Alabama


    Now I'm curious. Where are the enamel coatings used in an ORSC engine? Bearings? Turbine blades?, chamber walls? Everything exposed to oxygen?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: StvB on 08/09/2017 11:15 PM
    -Russian engines. I think, even as ULA has boosted, that they have RD-180 blueprints, Russian still have the secret sauce for oxygen-rich tech (-cough; porcelain enamel coating*; cough -). And like Jim says Blue doesn't have access for those.

    *"Currently, the Russian-developed enamel coatings are a far more mature and proven technology. However, application of these special coatings and/or advanced materials to U.S. ORSC engine designs has not been fully proven, so a comprehensive risk reduction program will be required."

    -Liquid Rocket Hydrocarbon Booster Engines (LRHCBE’s) for Launch Vehicles – A Status Report
    Robert L. Sackheim  Aerospace Propulsion Consultant, Huntsville, Alabama


    Now I'm curious. Where are the enamel coatings used in an ORSC engine? Bearings? Turbine blades?, chamber walls? Everything exposed to oxygen?

    From the document quoted by HVM:
    Quote
    It is well known that Russian engine designs have overcome this material incompatibility challenge by using inert enamel coatings on traditional high-strength turbine alloys and hot-gas ducting. The alloys provide the structural load support, while the enamel coating provides the requisite hot-oxygen-rich environment protection for various exposed surfaces.

    And a link should you wish to read more: http://guest.warr.de/Archiv/Konferenzen/EUCASS_2013_Papers/full/p596.pdf (http://guest.warr.de/Archiv/Konferenzen/EUCASS_2013_Papers/full/p596.pdf)

    Is this something that Blue will certainly need to overcome on the BE-4 or is a `medium-performing version of a high-performance design' somehow able to get away without such enamel coatings? If the speculating is true that they'll gradually improve to be a high-performing version, then maybe it is eventually unavoidable.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: gongora on 08/10/2017 12:32 AM
    Is this something that Blue will certainly need to overcome on the BE-4 or is a `medium-performing version of a high-performance design' somehow able to get away without such enamel coatings? If the speculating is true that they'll gradually improve to be a high-performing version, then maybe it is eventually unavoidable.

    Based on past hints we've seen the new engines may be using nickel superalloys that weren't in common use when the Russians first designed their engines.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: flyright on 08/10/2017 02:35 PM

    ...

    And a link should you wish to read more: http://guest.warr.de/Archiv/Konferenzen/EUCASS_2013_Papers/full/p596.pdf (http://guest.warr.de/Archiv/Konferenzen/EUCASS_2013_Papers/full/p596.pdf)

    ...


    Thanks for this link! Lots of good info in this paper.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: su27k on 08/26/2017 04:33 AM
    Someone posted this on /r/BlueOrigin under the subject "New Commemorative Patch", hopefully this means we'll have some good news about BE-4 soon.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: StvB on 08/26/2017 04:06 PM
    Someone posted this on /r/BlueOrigin under the subject "New Commemorative Patch", hopefully this means we'll have some good news about BE-4 soon.

    Thanks for sharing! Any ideas/guesses about the symbols? Google translates "conando ascendimus" to "trying to climb". There's what looks to be a roadrunner, eight stars, and 8-9 arrows, one of which is red with what looks like an explosion at the end.

    It's also being called a "Commemorative" patch by the original poster on r/blueorigin.

    Some kind of test milestone, possibly? What are the yellow lines on the engine meant to represent?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: JH on 08/27/2017 06:47 PM
    More literally (and figuratively) accurate translations would be: "By striving, we ascend" or "We rise by exerting ourselves", or even "We rise by trying to rise" if you are in a tautological mood.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: coal_burner on 08/28/2017 12:31 PM
    on the lower right, there are 9 lines.
    does the fact that the 2nd line is red signify that they are working on the 2nd step in a 9 step master plan?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: spacenut on 08/28/2017 12:46 PM
    Does anyone know a timeframe for another test?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Rebel44 on 08/28/2017 05:52 PM
    Does anyone know a timeframe for another test?

    When it was announced in 2014, full scale testing was expected in 2016 and first flight in 2019.  I suppose one must add one year to each number at this point.  We're getting close to needing to add two years.  When was AR-1 supposed to be ready again?

     - Ed Kyle

    1st full scale full power test of AR-1 is expected in 2019 (if things go as planned...)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: woods170 on 08/28/2017 07:19 PM
    Does anyone know a timeframe for another test?

    When it was announced in 2014, full scale testing was expected in 2016 and first flight in 2019.  I suppose one must add one year to each number at this point.  We're getting close to needing to add two years.  When was AR-1 supposed to be ready again?

     - Ed Kyle
    I'll bite Ed. AR-1 will be delayed just as much. No schedule ever holds in engine development. You of all people should know that.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Chasm on 08/29/2017 04:24 AM
    on the lower right, there are 9 lines.
    does the fact that the 2nd line is red signify that they are working on the 2nd step in a 9 step master plan?

    9 lines, 1 of them red.
    8 stars, none of them red.

    Perhaps representing the number of test milestones (engines) and their major Oops?
    (Terraserver imagery is from ~1 week before the oops, and nothing since. Frustrating)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Robotbeat on 08/30/2017 01:13 PM
    Try imagery on planet.com because it's updated at least once a week and sometimes daily.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Chasm on 08/30/2017 01:57 PM
    Got (free) accounts for both, there are not enough details on planet.
    planet.com imagery is 3m resolution, terraserver is 0.5m

    I was looking for signs of the big oops, trying to find out how big it was. The difference even in the preview is truly massive. Planet has blobs, on terraserver you can easily see details, i.e. wich way a car is parked. Or on a bigger  scale you can distinguish single tanks, on planet the get grouped into unidentifiable blobs. To try damage assessment terraserver has test stand details like grinders/scaffolding that might get damaged in a major blowup.


    There are of course other image companies but the ones I tried so far need paid accounts for high res previews. I'm not that interested. :)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: jpo234 on 09/01/2017 08:04 AM
    on the lower right, there are 9 lines.
    does the fact that the 2nd line is red signify that they are working on the 2nd step in a 9 step master plan?

    9 lines, 1 of them red.
    8 stars, none of them red.

    Perhaps representing the number of test milestones (engines) and their major Oops?
    (Terraserver imagery is from ~1 week before the oops, and nothing since. Frustrating)

    Someone pointed out that the engine bell at the end of the red line seems to be incomplete (it is wider above the red line than below it). This could mean, that the lines represent the lasers of the additive manufacturing used to make the BE-4.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: saliva_sweet on 09/06/2017 06:55 PM
    Is Blue Origin planning to colonize Mars now?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: testguy on 09/07/2017 07:05 PM
    IAC 2017 is getting close.  I would imagine if Blue has made significant progress on BE-4 there would be an announcement prior to Elon's next reveal.  Let's remember the competition between Jeff and Elon.  Wasn't there some one ups men ship last year at this time.  Let's hope that Blue has good news to share.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: spacenut on 09/07/2017 07:27 PM
    From what I understand, the first test of BE-4 failed.  The sub-scale test of Raptor was a success.  The first sub-scale test of AR-1 was a success.  Is this correct?  If so, seems as if BE-4 is falling behind. 
    Title: Re: Blue Origin's BE-4 Engine
    Post by: DJPledger on 09/07/2017 07:29 PM
    From what I understand, the first test of BE-4 failed.  The sub-scale test of Raptor was a success.  The first sub-scale test of AR-1 was a success.  Is this correct?  If so, seems as if BE-4 is falling behind. 
    A BE-4 powerpack failed earlier this year. Are you referring to this or has a full BE-4 engine failed recently?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 09/07/2017 08:07 PM
    Not right either. All we know is that there was a failure in test earlier this year, and that the failure that occurred was traced to the power pack/head.

    We don't know the context of the failure, nor the scope of what needed to be replaced/reworked/rebuilt.

    Although given the hint that they'd restart testing in "late summer" (e.g. "now"), that suggests a significant amount of work to recover.

    Before they started this test sequence, they had spent time assembling multiple complete, full scale engines, and had done extensive testing of the powerpack (usually, this means that you convince yourself that this part of the engine has sufficient mass flow / stability / reliability to support a full scale engine on a test stand. (They had mentioned that they'd had some failures of the powerpack while proving it.)

    Make no mistake - proving a powerpack to an engine of this scale is hard - note the F-1B powerpack test that was done a few years back. But then you typically attach an injector/combustion chamber next, in order to validate operation in start up / shut down / "burp". So it's hard to believe they were just testing the powerpack again.

    Also, the test stand they were likely using appeared to have multiple cells, which makes sense, because you could then destroy a cell and use another while repairs could proceed on the destroyed cell.

    The only exception to this is where the damage was larger than the cell, taking out the entire stand. Which would cause a multi-month delay like we're seeing.

    This work is very tedious and often "goes backward". Redesign/rebuild/reprove/retest. With ORSC, you could end up in a "free fall" for a while, until things start working once again. Likely here.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: rsdavis9 on 09/07/2017 08:35 PM
    so raptor is a FFSC. Full Flow Staged Combustion and therefore one half of it is ORSC Oxygen Rich Staged Combustion. So Spacex has the same problems as Blue?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: john smith 19 on 09/07/2017 08:37 PM
    Make no mistake - proving a powerpack to an engine of this scale is hard - note the F-1B powerpack test that was done a few years back. But then you typically attach an injector/combustion chamber next, in order to validate operation in start up / shut down / "burp". So it's hard to believe they were just testing the powerpack again.

    This work is very tedious and often "goes backward". Redesign/rebuild/reprove/retest. With ORSC, you could end up in a "free fall" for a while, until things start working once again. Likely here.
    Indeed.
    It seems people have forgotten that the SSME destroyed 11 poweheads just to work out the start sequence.  :(

    No one's built an ORSC in the US before. While it's true there has been a quantum leap in both diagnostics and processing power to model what's happening before a single hardware test cycle is attempted SC engines are much more interelated than GG cycle engines.

    One of the SSME test rigs had 2000 valves to simulate the rest of the engine that had not been built. It really does seem the best way to build one of these is heavily simulate first, then build the first one fast and expect to build a bunch more 

    In hindsight, depending on how far through the test programme they are, it may be quite impressive they've only destroyed one power pack so far.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 09/07/2017 08:55 PM
    so raptor is a FFSC. Full Flow Staged Combustion and therefore one half of it is ORSC Oxygen Rich Staged Combustion. So Spacex has the same problems as Blue?
    This is OT here.

    In short - nope, not the same. Each side FR/OR splits total flow. FFSC problem is it must all work, at once, together, at the same time. Kind of an all or nothing. Not separable.

    Back to topic - ORSC requires a high common mass flow of a highly reactive intermediate product, through into a combustion chamber before it combusts too far. You can easily consume / detonate the engine before you reach the combustion chamber ... which is likely what is happening here. Which is why it wasn't thought practical by American engine designers decades back.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: john smith 19 on 09/08/2017 02:55 PM
    This report said that Blue suffered a power pack explosion in 2015, prior to this year's May power pack explosion.

    http://spacenews.com/ula-intends-to-lower-its-costs-and-raise-its-cool-to-compete-with-spacex/

     - Ed Kyle
    Thanks. I did not realize there was a recording of Tobey career ending seminar.

    Note the piece talks of a whole engine on a stand, but no indication of wheather this was the BE-3, BE-4 or something else, so it's unclear if this is the first or second RUD in the BE-4 development programme.

    In my mind I keep seeing the frontispiece of Clarke's "Ignition" of the engine test cell working normally, and the engine test cell when things go wrong.  :(

    It's only a test failure if you a) Didn't get any of the data you wanted and b)Have no idea why the engine failed and c) Have no idea how to fix it.   :(

    As long as you've got something on one (or more) of those (and funds to rebuild) you can keep moving forward.

    As I noted SSME destroyed 11 powerheads just to develop the start sequence. At least one was due to a sensor misalignment of 1 degree in measuring a key valve opening and I suspect some were due to the fact that LH2 is compressible (at engine pressures) in a way virtually no other common fluid is.  :(

    In hindsight, expecting a RUD free development programme from large rocket engines with a new complex combustion cycle, regardless of the development teams experience with other cycles, should have been seen as a low probability event. It was a case of when, not if one of them would suffer a RUD.

    Title: Re: Blue Origin's BE-4 Engine
    Post by: mgeagon on 09/10/2017 04:35 AM
    so raptor is a FFSC. Full Flow Staged Combustion and therefore one half of it is ORSC Oxygen Rich Staged Combustion. So Spacex has the same problems as Blue?

    One of the safety concerns about either ORSC or FRSC is the shared turbine shaft with the reactant's fuel pump. Unless a very good seal is used, very highly pressurized hot oxidizer (in BE04's case) can escape into the fuel line (LNG) as it enters the axial flow compressor, creating an extremely volatile mixture that will likely explode. We do not yet know whether this was the cause of the mishap in May.

    This is not a concern with FFSC, because exhaust from both pre-burners only turns their respective fuel pumps. No mixing of reactants is possible.

    The raptor is certainly more complex than the BE04, since the former has two pre-burners and two turbine shafts, rather than the latter's one, but in this one specific area, the FFSC engine does have an advantage.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: DJPledger on 09/10/2017 08:29 AM
    so raptor is a FFSC. Full Flow Staged Combustion and therefore one half of it is ORSC Oxygen Rich Staged Combustion. So Spacex has the same problems as Blue?

    One of the safety concerns about either ORSC or FRSC is the shared turbine shaft with the reactant's fuel pump. Unless a very good seal is used, very highly pressurized hot oxidizer (in BE04's case) can escape into the fuel line (LNG) as it enters the axial flow compressor, creating an extremely volatile mixture that will likely explode. We do not yet know whether this was the cause of the mishap in May.

    This is not a concern with FFSC, because exhaust from both pre-burners only turns their respective fuel pumps. No mixing of reactants is possible.

    The raptor is certainly more complex than the BE04, since the former has two pre-burners and two turbine shafts, rather than the latter's one, but in this one specific area, the FFSC engine does have an advantage.
    Perhaps BO should redesign the BE-4 as a FFSC engine to remove the issue mentioned above and to improve performance. BO should have made BE-4 FFSC in the first place. Maybe their next engine after BE-4 will be FFSC.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Rebel44 on 09/10/2017 08:38 AM
    so raptor is a FFSC. Full Flow Staged Combustion and therefore one half of it is ORSC Oxygen Rich Staged Combustion. So Spacex has the same problems as Blue?

    One of the safety concerns about either ORSC or FRSC is the shared turbine shaft with the reactant's fuel pump. Unless a very good seal is used, very highly pressurized hot oxidizer (in BE04's case) can escape into the fuel line (LNG) as it enters the axial flow compressor, creating an extremely volatile mixture that will likely explode. We do not yet know whether this was the cause of the mishap in May.

    This is not a concern with FFSC, because exhaust from both pre-burners only turns their respective fuel pumps. No mixing of reactants is possible.

    The raptor is certainly more complex than the BE04, since the former has two pre-burners and two turbine shafts, rather than the latter's one, but in this one specific area, the FFSC engine does have an advantage.
    Perhaps BO should redesign the BE-4 as a FFSC engine to remove the issue mentioned above and to improve performance. BO should have made BE-4 FFSC in the first place. Maybe their next engine after BE-4 will be FFSC.

    That would mean developing a completely new engine - not just a minor modification...
    Title: Re: Blue Origin's BE-4 Engine
    Post by: AncientU on 09/10/2017 11:52 AM
    We've all been discussing whether Blue's BE-4 or Aerojet's AR-1 will be the Vulcan's engine... assuming that both will have successful development programs.  It is possible that neither will develop a reliable ORSC engine in the next five years (or ever).

    Maybe that's why ULA is buying RD-180s to cover Atlas-V flights out to mid-2020s...
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 09/10/2017 06:33 PM
    Perhaps BO should redesign the BE-4 as a FFSC engine to remove the issue mentioned above and to improve performance. BO should have made BE-4 FFSC in the first place. Maybe their next engine after BE-4 will be FFSC.
    Nonsense. And add another decade of delay?

    It's just the luck of the draw, and the skill of the designers. Note that SX isn't out of the woods yet - engine hasn't accumulated any flight history yet. They got over a key hump (they got enough on the first try to know they can get what they wanted) and can move from demonstration to application.

    For BO/AJR, they chose the best designs for themselves to execute on and are executing it. BO needs to work through to a functioning design (iteration and test), then assess what they've got after - does it do what they need. AJR likely fears what BO is going through as their future, wishing for what SX got as the optimum.

    Note that all three are working with propellants that are new to them (SX had kero, AJR/BO had hydrogen). Significant.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: DJPledger on 09/10/2017 07:21 PM
    We've all been discussing whether Blue's BE-4 or Aerojet's AR-1 will be the Vulcan's engine... assuming that both will have successful development programs.  It is possible that neither will develop a reliable ORSC engine in the next five years (or ever).

    Maybe that's why ULA is buying RD-180s to cover Atlas-V flights out to mid-2020s...
    FFSC has the potential to be much more reliable than both ORSC which the BE-4 uses and FRSC as it eliminates the interpropellant seal which is a potential serious failure mode. The failure of the BE-4 powerpack may have been caused by unwanted propellant mixing causing an explosion. Such a failure would not have happened if BO had selected FFSC for BE-4. Hopefully they will learn their lesson and use FFSC for their next engine after BE-4 which NA will use. FFSC at BE-4's Pc should be extremely reliable.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Ictogan on 09/10/2017 08:01 PM
    We've all been discussing whether Blue's BE-4 or Aerojet's AR-1 will be the Vulcan's engine... assuming that both will have successful development programs.  It is possible that neither will develop a reliable ORSC engine in the next five years (or ever).

    Maybe that's why ULA is buying RD-180s to cover Atlas-V flights out to mid-2020s...
    FFSC has the potential to be much more reliable than both ORSC which the BE-4 uses and FRSC as it eliminates the interpropellant seal which is a potential serious failure mode. The failure of the BE-4 powerpack may have been caused by unwanted propellant mixing causing an explosion. Such a failure would not have happened if BO had selected FFSC for BE-4. Hopefully they will learn their lesson and use FFSC for their next engine after BE-4 which NA will use. FFSC at BE-4's Pc should be extremely reliable.
    So you are saying that the failure may have been caused by it, but you are claiming that their failure wouldn't have happened if they were using FFSC(without any mention of the word "may"). Right... Either you have some insider info or you are taking your own speculation as fact.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: gongora on 09/10/2017 08:15 PM
    You know how many FFSC engines are flying?  NONE.  The Russians have been reliably flying ORSC for DECADES.  It's not at all obvious that Blue should have gone a different route just because a couple of ya'll read about a possible failure mode on Wikipedia.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 09/10/2017 10:12 PM
    The irony of the moment (which I fear just causes silly posts to happen when I bring it up) is that it is highly likely that SX has brought up an 1+MN engine that is in the class of what Vulcan desires badly right now (no, it's not designed for it, nor are the two companies exactly best buddies right now).

    Yet as far as we've heard, ... SX has no plans to use that particular engine, just follow on ones in the family of much larger scale.

    (Am rather frugal by habit. Simply irks to know you could use something to get further that's cognitively within reach.) Has nothing to do with anything else (capability of the designers, funding level of development, engine cycle, ...). Also, have seen rivals negotiate deals in the past like this.

    BO has many, many months to get it right, so there's no deadline either. And a efficient ORSC methalox second generation design could quite likely outperform RD-170/180/190 equivalent combinations also, for NG/NA longer term. It's only ULA that's caught up by this ATM. Have even less confidence in AR-1's full scale passage onto test stand - remember, both have to hurdle this same perilous vault.

    (And when you scale up FFSC, you can have surprises of non-uniform mixing too. Nothing's a sure win.) So this is more of a 'bird in the hand" thing.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: AncientU on 09/10/2017 10:40 PM
    You know how many FFSC engines are flying?  NONE.  The Russians have been reliably flying ORSC for DECADES.  It's not at all obvious that Blue should have gone a different route just because a couple of ya'll read about a possible failure mode on Wikipedia.

    Totally agree. 
    ORSC was the logical goal for Blue and AJR -- and really for SpaceX, too.  But it seems there is a reason ORSC has been called impossible... at least very difficult.  Soviet, now Russian, technology is not easy to replicate sometimes... (Another example: The Soviets were also using planetary gear trains on their submarines for decades and the US of A couldn't figure out how to make them reliably.)

    What was a little crazy, was for SpaceX to go after FFSC -- a huge leap from GG Merlin.

    Crazy like a fox?  We'll see...
    Title: Re: Blue Origin's BE-4 Engine
    Post by: mgeagon on 09/10/2017 10:45 PM
    You know how many FFSC engines are flying?  NONE.  The Russians have been reliably flying ORSC for DECADES.  It's not at all obvious that Blue should have gone a different route just because a couple of ya'll read about a possible failure mode on Wikipedia.

    Rocket engines blow up all the time. I am sure the Raptor has had its fair share and will likely have more. ORSC is not an inherently inferior design by any measure, as its successful flight rate can attest. Two of the most challenging aspects of the configuration are interseal failure and developing metallurgy to counter the corrosive effects of high-pressure oxidizer (The oxidizer side of a FFSC motor has less pressure because it only has to drive one fuel pump). As Gongora pointed out, the RD-170 family solved these problems decades ago, and so Blue will undoubtedly find a solution. It may not be clear how gradually that final design might come.

    There are significant advantages to a monofuel pre-burner, single shaft staged combustion engine. Foremost is the relative simplicity (fewer moving parts) and the resultant reduction in weight. Blue is seeking resuability rather than maximum performance, but an O/FRSC motor should yield the best T/W ratio for a given propellant. (How Merlin holds that title for RP1 with it's GG is another story). The BE4 design was likely chosen because it will eventually be the lightest and most reliable way to utilize LNG. SpaceX has gone a different direction for a number of reasons, but both companies have very objective rationale and each likely made the right call.

    Title: Re: Blue Origin's BE-4 Engine
    Post by: pippin on 09/10/2017 10:52 PM
    We've all been discussing whether Blue's BE-4 or Aerojet's AR-1 will be the Vulcan's engine... assuming that both will have successful development programs.  It is possible that neither will develop a reliable ORSC engine in the next five years (or ever).

    Maybe that's why ULA is buying RD-180s to cover Atlas-V flights out to mid-2020s...
    FFSC has the potential to be much more reliable than both ORSC which the BE-4 uses and FRSC as it eliminates the interpropellant seal which is a potential serious failure mode. The failure of the BE-4 powerpack may have been caused by unwanted propellant mixing causing an explosion. Such a failure would not have happened if BO had selected FFSC for BE-4. Hopefully they will learn their lesson and use FFSC for their next engine after BE-4 which NA will use. FFSC at BE-4's Pc should be extremely reliable.
    Do you have any information about the reason for their failure or are you just spreading FUD?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: lrk on 09/10/2017 11:10 PM
    This report said that Blue suffered a power pack explosion in 2015, prior to this year's May power pack explosion.

    http://spacenews.com/ula-intends-to-lower-its-costs-and-raise-its-cool-to-compete-with-spacex/

     - Ed Kyle
    Thanks. I did not realize there was a recording of Tobey career ending seminar.

    Note the piece talks of a whole engine on a stand, but no indication of wheather this was the BE-3, BE-4 or something else, so it's unclear if this is the first or second RUD in the BE-4 development programme.

    In my mind I keep seeing the frontispiece of Clarke's "Ignition" of the engine test cell working normally, and the engine test cell when things go wrong.  :(

    It's only a test failure if you a) Didn't get any of the data you wanted and b)Have no idea why the engine failed and c) Have no idea how to fix it.   :(

    As long as you've got something on one (or more) of those (and funds to rebuild) you can keep moving forward.

    As I noted SSME destroyed 11 powerheads just to develop the start sequence. At least one was due to a sensor misalignment of 1 degree in measuring a key valve opening and I suspect some were due to the fact that LH2 is compressible (at engine pressures) in a way virtually no other common fluid is.  :(

    In hindsight, expecting a RUD free development programme from large rocket engines with a new complex combustion cycle, regardless of the development teams experience with other cycles, should have been seen as a low probability event. It was a case of when, not if one of them would suffer a RUD.

    IIRC it was a BE-3 that failed, something went wrong when attempting in-flight restart testing for New Shepherd. 
    Title: Re: Blue Origin's BE-4 Engine
    Post by: rsdavis9 on 09/11/2017 01:03 PM
    Is it correct to assume that both companies have rd-180 engines to take apart and analyze? (BO and aerojet). How much can be learned from these russian engines?
    1. Mechanics (easy?)
    2. Materials (harder?)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: matthewkantar on 09/11/2017 04:06 PM
    Without accusing anybody of anything illegal, Bezos did recover the remains of a Saturn V first stage from the Atlantic. The seafloor is littered with Atlas/RD-180 stages, grabbing one on the sly would be easy, and maybe even legal.

    I am not sure how useful the knowledge gained would be. Copying is of course off the table, but an exotic technology like this may be able to teach some lessons.

    Matthew
    Title: Re: Blue Origin's BE-4 Engine
    Post by: oldAtlas_Eguy on 09/11/2017 04:15 PM
    The best lesson to an engineer is knowing something can be done. Not necessarily how it can be done. This is where innovation comes in and discovery of better (and worse) solutions to the same problem.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: mn on 09/11/2017 04:24 PM
    ....The seafloor is littered with Atlas/RD-180 stages, grabbing one on the sly would be easy, and maybe even legal...

    Matthew

    Finding a living person who worked on these engines might be easier and might even give better results ;)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Nomadd on 09/11/2017 04:33 PM
    We've all been discussing whether Blue's BE-4 or Aerojet's AR-1 will be the Vulcan's engine... assuming that both will have successful development programs.  It is possible that neither will develop a reliable ORSC engine in the next five years (or ever).

    Maybe that's why ULA is buying RD-180s to cover Atlas-V flights out to mid-2020s...
    FFSC has the potential to be much more reliable than both ORSC which the BE-4 uses and FRSC as it eliminates the interpropellant seal which is a potential serious failure mode. The failure of the BE-4 powerpack may have been caused by unwanted propellant mixing causing an explosion. Such a failure would not have happened if BO had selected FFSC for BE-4. Hopefully they will learn their lesson and use FFSC for their next engine after BE-4 which NA will use. FFSC at BE-4's Pc should be extremely reliable.
    Do you have any information about the reason for their failure or are you just spreading FUD?
    It's kind of obvious that a failure caused by interpropellant seal wouldn't have happened is there was no such seal.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Ictogan on 09/11/2017 04:34 PM
    We've all been discussing whether Blue's BE-4 or Aerojet's AR-1 will be the Vulcan's engine... assuming that both will have successful development programs.  It is possible that neither will develop a reliable ORSC engine in the next five years (or ever).

    Maybe that's why ULA is buying RD-180s to cover Atlas-V flights out to mid-2020s...
    FFSC has the potential to be much more reliable than both ORSC which the BE-4 uses and FRSC as it eliminates the interpropellant seal which is a potential serious failure mode. The failure of the BE-4 powerpack may have been caused by unwanted propellant mixing causing an explosion. Such a failure would not have happened if BO had selected FFSC for BE-4. Hopefully they will learn their lesson and use FFSC for their next engine after BE-4 which NA will use. FFSC at BE-4's Pc should be extremely reliable.
    Do you have any information about the reason for their failure or are you just spreading FUD?
    It's kind of obvious that a failure caused by interpropellant seal wouldn't have happened is there was no such seal.
    But is there any information on whether the failure had anything to do with the interpropellant seal?
    Title: Blue Origin's BE-4 Engine
    Post by: pippin on 09/11/2017 06:16 PM
    Oh, Nomadd is right, they only tested the power pack, right? No interpropellant seal, no main propellant flow, no main propellant flow related failure modes. So how could the failure be related to the interpropellant seal?

    Title: Re: Blue Origin's BE-4 Engine
    Post by: envy887 on 09/11/2017 08:44 PM
    Oh, Nomadd is right, they only tested the power pack, right? No interpropellant seal, no main propellant flow, no main propellant flow related failure modes. So how could the failure be related to the interpropellant seal?

    So again: how about stopping to spread FUD?

    Nomadd's point was that FFSC by design cannot possibly have an inter-propellant seal failure, since it does not have such a seal.

    AIUI the powerpack testing necessarily requires the interpropellant seal, since the powerpack includes the oxidizer rich turbine driving both pumps.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: john smith 19 on 09/11/2017 11:02 PM
    FFSC has the potential to be much more reliable than both ORSC which the BE-4 uses and FRSC as it eliminates the interpropellant seal which is a potential serious failure mode. The failure of the BE-4 powerpack may have been caused by unwanted propellant mixing causing an explosion. Such a failure would not have happened if BO had selected FFSC for BE-4. Hopefully they will learn their lesson and use FFSC for their next engine after BE-4 which NA will use. FFSC at BE-4's Pc should be extremely reliable.
    Quite true in theory.

    However I've seen quite a few Aerojet design studies in the archives and they really did love the FFSC cycle (along with really high O/F ratios)

    Yet when Congress (through the USAF) put money on the table what did they go for?

    BTW the SSME was an FRSC  and in flight I don't think it ever suffered an interpropellant seal failure.

    What FFSC would have done would have eliminated one of those large 300lb GHe tanks, radically improving the T/W ratio.

    BTW part of their size was because the seal leakage was about 3-4x what it was forecast to be. Modern seal designs (EG the brush) can deliver the leakage rates that the SSME was originally expected to have, using the simplistic models available at the time of its initial specification.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 09/12/2017 01:24 AM
    Suggest different ambitions for chamber pressure drove the BO/SX design choices.

    For SX, the ambition was for a high chamber pressure from the very start, to gain a very compact engine with higher than Merlin TWR. For more power, they'd scale the entire engine to meet requirement.

    For BO, the ambition was for a low chamber pressure so as to have a 'good enough", quick win to get engines into a vehicle quickly. Then, like with Merlin's relentless cycle of improvements, they'd push up the chamber pressure on subsequent revisions of uprating.

    The choice of the higher chamber pressure drove the need for FFSC. The lower pressure engine could be simpler in design, so bearings and other considerations could take into account less wear in operation, thus the selection of ORSC. Perhaps they did not see the interpropellant seal as much of a challenge? Possibly because the propellant's nature offered the expectation of manageable partial combustion mass flows, less chaotic than kerolox/hydrolox?

    This is where scaling makes things less predictable in practice.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: mgeagon on 09/12/2017 02:55 AM
    FFSC has the potential to be much more reliable than both ORSC which the BE-4 uses and FRSC as it eliminates the interpropellant seal which is a potential serious failure mode. The failure of the BE-4 powerpack may have been caused by unwanted propellant mixing causing an explosion. Such a failure would not have happened if BO had selected FFSC for BE-4. Hopefully they will learn their lesson and use FFSC for their next engine after BE-4 which NA will use. FFSC at BE-4's Pc should be extremely reliable.
    Quite true in theory.

    However I've seen quite a few Aerojet design studies in the archives and they really did love the FFSC cycle (along with really high O/F ratios)

    Yet when Congress (through the USAF) put money on the table what did they go for?

    BTW the SSME was an FRSC  and in flight I don't think it ever suffered an interpropellant seal failure.

    What FFSC would have done would have eliminated one of those large 300lb GHe tanks, radically improving the T/W ratio.

    BTW part of their size was because the seal leakage was about 3-4x what it was forecast to be. Modern seal designs (EG the brush) can deliver the leakage rates that the SSME was originally expected to have, using the simplistic models available at the time of its initial specification.

    IIRC, The SSME used a continuous flow of GHe through the turbine shaft cavities to expel preburned H to mitigated the leakage. It is one of the many reasons the engines needed extensive refurbishment between each mission and increased total weight of the orbiter due to the additional helium and tanks required. Refurbishment is not a concern with the RS-25s going into the SLS for obvious reasons. While many rocket designs utilize helium purges to remove explosive gases during shutdown, for example, it does not seem likely any modern engine developer would wish to include this type of interseal redundancy scheme.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: john smith 19 on 09/12/2017 06:26 PM
    IIRC, The SSME used a continuous flow of GHe through the turbine shaft cavities to expel preburned H to mitigated the leakage. It is one of the many reasons the engines needed extensive refurbishment between each mission and increased total weight of the orbiter due to the additional helium and tanks required. Refurbishment is not a concern with the RS-25s going into the SLS for obvious reasons. While many rocket designs utilize helium purges to remove explosive gases during shutdown, for example, it does not seem likely any modern engine developer would wish to include this type of interseal redundancy scheme.
    This is one of those "in theory no, in practice yes" problems that most real engines do have to do.

    Rocket engine design 101.
    IRL nearly all big engines are driven by propellants pressurized by a pair of pumps.
    Those pumps are nearly always driven by turbines.
    Those turbines are nearly always driven by a stream of combustion gases which, for either performance or thermal management reasons is rich in one of the propellants. Therefore the seal between that turbine, and the opposite propellant whose pump it's driving, is always a criticality 1 failure point.  :(

    That said Soyuz uses a turbopump propelled by an Oxygen rich steam flow from the breakdown of Hydrogen Peroxide (so possible issue with it pumping fuel) and the RL10 uses "hot" GH2 (actually about -58c, which is hot by the standards of LH2 :) ) but the LOX pump is driven through a gearbox.

    The key issues with these systems are a) What's the pressure difference between the 2 sides (ihigher is tougher)  and b)Can the interseal space be vented, and if so where to?

    In reality I'm not sure I've ever heard of an engine RUD traced to a seal leak. What it does do is add mechanical complexity and the need for either inert gas gas or a vacuum (well a low pressure region to suck the inter seal gap into) source. Only things like the dual expander "Broadsword" of Masten or the GHe drive of SABRE avoid these problems but most people (especially the Russian ORSC engines) cope with them without a major problem
    Title: Re: Blue Origin's BE-4 Engine
    Post by: su27k on 09/15/2017 03:50 AM
    https://twitter.com/JeffBezos/status/908124621391618050

    The tweet has nothing to do with space, but I think that's a (partially assembled) BE-4 in the background.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: mgeagon on 09/15/2017 08:12 AM
    https://twitter.com/JeffBezos/status/908124621391618050

    The tweet has nothing to do with space, but I think that's a (partially assembled) BE-4 in the background.

    Combustion chamber, nozzle and bell. Could be headed to "one" of the powerpacks for mounting. Might be a good sign that testing is underway again.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: ChaoticFlounder on 09/15/2017 11:36 PM
    A couple things:

    First, do we know from Blue Origin any information other than "a powerpack failed on the test stand?"

    Second, can you give clarity on what defines the line between a "Full Flow" Staged Combustion engine and a "Regular" Staged Combustion engine?

    Third, turbine drive engines will usually have an "interpropellant seal" somewhere, save FFSC designs that I have seen to date.  Merlin should have one, F-1 had one, SSME has one, RL-10 should have one somewhere.  To my knowledge, it is not possible to get a perfect seal.  Even valves that are stationary have a minute leak rate.  It gets a little more difficult when you have a shaft spinning at 15,000 RPM and this is what drives the need for the inert gas.

    C

    Oh, edited to attach some interesting info about some things that can go wrong...
    Title: Re: Blue Origin's BE-4 Engine
    Post by: brickmack on 09/16/2017 04:41 AM
    No such thing as a "regular" staged combustion engine. Either fuel rich, oxidizer rich, or full flow. Fuel rich, all of the fuel goes through the turbine and a small amount of it is burned with a small amount of the oxidizer, that combustion spins the pump to push oxidizer through the engine while the hot gassified fuel goes into the main combustion chamber and burns with the still liquid oxidizer. Ox rich is basically the same but the other way around. With both of these, you need an interpropellant seal because both propellants are going through the same turbopump, just on different sides, and if they interact before getting to the combustion chamber, boom. Full flow staged combustion has 2 totally separate turbopumps, where all of the fuel goes through one pump and all of the oxidizer goes through the other, excepting the tiny amount of the opposite needed by each for combustion in the turbopumps (hence, full flow), and both propellants are fully gassified when they go into the chamber. Since the propellants go through totally separate pumps, theres no need for a seal. Dual expander engines don't need a seal either for a similar reason, though to date no such engine has flown
    Title: Re: Blue Origin's BE-4 Engine
    Post by: ChaoticFlounder on 09/16/2017 05:54 AM
    No such thing as a "regular" staged combustion engine. Either fuel rich, oxidizer rich, or full flow. Fuel rich, all of the fuel goes through the turbine and a small amount of it is burned with a small amount of the oxidizer, that combustion spins the pump to push oxidizer through the engine while the hot gassified fuel goes into the main combustion chamber and burns with the still liquid oxidizer. Ox rich is basically the same but the other way around. With both of these, you need an interpropellant seal because both propellants are going through the same turbopump, just on different sides, and if they interact before getting to the combustion chamber, boom. Full flow staged combustion has 2 totally separate turbopumps, where all of the fuel goes through one pump and all of the oxidizer goes through the other, excepting the tiny amount of the opposite needed by each for combustion in the turbopumps (hence, full flow), and both propellants are fully gassified when they go into the chamber. Since the propellants go through totally separate pumps, theres no need for a seal. Dual expander engines don't need a seal either for a similar reason, though to date no such engine has flown

    Eh, have a look at the presentation attached below.  It seems that around 76% (which surprised me, i thought it was less) of the fuel goes to the two preburners and the rest is used for cooling and then ends up in the MCC (PDF Page 25-26, Labeled Page 19-20).  I'm saying this because you said "all".

    The reason I keep talking about the SSME here is it is a FRSC engine and it has 2 high pressure turbo pumps which run on the FRSC cycle, 1 LPHTP that runs on expander, and 1 LPOTP that runs off of high pressure lox discharge from the HPOTP.  What I haven't seen made very clear in the forums above is that FFSC and FRSC / ORSC are more similar than they are different.  Staged combustion (FRSC / ORSC) can come in a myriad of pump combinations as seen above and is not limited to a one-shaft turbopump like BO chose to use.  That was a design choice they chose to make.

    Also, there is an interesting bit in the attached PDF on shaft seals (PDF Page 70-71, Labeled Page 64-65).  This will give you an idea of the general design intent of it and how one may go about it.  I can speculate BE-4 may have a similar architecture, it may not... same goes for Space X's Merlin...

    Let me know if you have any questions or if I didn't explain something well.

    C

    Title: Re: Blue Origin's BE-4 Engine
    Post by: yokem55 on 09/16/2017 01:52 PM
    This article on the study done to convert the SSME to FFSC in the early 80's makes for an interesting, although one-sided, comparison of FFSC and FRSC.

    http://www.eaglehill.us/programs/journals/spaevo/2015a1/
    Title: Re: Blue Origin's BE-4 Engine
    Post by: testguy on 09/23/2017 07:27 PM
    Time for a bump.  With less than a week to IAC 17, if there is significant progress (good news) on BE-4, I would expect to hear early next week.  If nothing to report, I will start to be concerned.  They did start the test program hardware rich.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: ZachF on 09/24/2017 11:21 AM
    Time for a bump.  With less than a week to IAC 17, if there is significant progress (good news) on BE-4, I would expect to hear early next week.  If nothing to report, I will start to be concerned.  They did start the test program hardware rich.

    Hopefully we will see some nice videos of both the BE-4 and Raptor spitting some pretty blue flames.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: ChaoticFlounder on 09/24/2017 03:34 PM
    Time for a bump.  With less than a week to IAC 17, if there is significant progress (good news) on BE-4, I would expect to hear early next week.  If nothing to report, I will start to be concerned.  They did start the test program hardware rich.

    I think we all hope to see something new from Blue.  What I think we are all worried about is that they had to make a design change that sent all of the extra hardware to the scrap bin.  (i.e. maybe switching from hydrostatic bearings to more conventional ball and roller bearings like the ssme turbomachinery uses.)

    Like has been stated before, only time will tell.

    C
    Title: Re: Blue Origin's BE-4 Engine
    Post by: DJPledger on 09/24/2017 07:41 PM
    Time for a bump.  With less than a week to IAC 17, if there is significant progress (good news) on BE-4, I would expect to hear early next week.  If nothing to report, I will start to be concerned.  They did start the test program hardware rich.

    I think we all hope to see something new from Blue.  What I think we are all worried about is that they had to make a design change that sent all of the extra hardware to the scrap bin.  (i.e. maybe switching from hydrostatic bearings to more conventional ball and roller bearings like the ssme turbomachinery uses.)

    Like has been stated before, only time will tell.

    C
    There is no need to be worried as BO have more than enough money to afford a redesign of the BE-4 and they are not in any particular rush to do anything. Hopefully we will get something new on BE-4 during IAC2017.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Rebel44 on 09/24/2017 08:04 PM
    Time for a bump.  With less than a week to IAC 17, if there is significant progress (good news) on BE-4, I would expect to hear early next week.  If nothing to report, I will start to be concerned.  They did start the test program hardware rich.

    I think we all hope to see something new from Blue.  What I think we are all worried about is that they had to make a design change that sent all of the extra hardware to the scrap bin.  (i.e. maybe switching from hydrostatic bearings to more conventional ball and roller bearings like the ssme turbomachinery uses.)

    Like has been stated before, only time will tell.

    C
    There is no need to be worried as BO have more than enough money to afford a redesign of the BE-4 and they are not in any particular rush to do anything. Hopefully we will get something new on BE-4 during IAC2017.

    But its a problem for ULA, which needs to downselect engine for Vulcan ASAP.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: ChaoticFlounder on 09/24/2017 08:32 PM
    But its a problem for ULA, which needs to downselect engine for Vulcan ASAP.

    You are right, it's times like these that big boy decisions get made and we get to see what Tory Bruno is made of  :).

    P.S. - I don't doubt his ability one bit, I'm watching and hope I can learn something about leadership from this...
    Title: Re: Blue Origin's BE-4 Engine
    Post by: ChaoticFlounder on 09/25/2017 03:22 AM
    But its a problem for ULA, which needs to downselect engine for Vulcan ASAP.

    You are right, it's times like these that big boy decisions get made and we get to see what Tory Bruno is made of  :).

    P.S. - I don't doubt his ability one bit, I'm watching and hope I can learn something about leadership from this...

    Don't put too much stock on that. He's just as human, and the ULA "parents" are about as coldly pathological as any. He cares about the survival of ULA long term, which was why attempting BE-4 was an extremely good idea, but there's only so long that he can wait before "falling back" to AR-1 becomes necessary.

    The "parents" believe they can twist AJR's arm enough, for a marginally successful ULA. Perhaps they will learn to become immune to "iocane poison"?

    I agree with you 100% Mr. Ghost.  Everybody's human, I'm just interested to see how he balances all the possible problems you mentioned and comes out in the end.  I think we all can agree Mr. Bruno has some swift and turbulent waters to navigate.  It's stuff like this that really separates good leaders from meh ones.

    C
    Title: Re: Blue Origin's BE-4 Engine
    Post by: FutureSpaceTourist on 09/26/2017 07:41 AM
    Not the most effusive statement:

    Quote
    Meyerson: we have made “measurable progress” on BE-4 engine this year, with more engines in the pipeline. #IAC2017

    https://twitter.com/jeff_foust/status/912479192444420096 (https://twitter.com/jeff_foust/status/912479192444420096)

    In a follow-up tweet Jeff clarified it’s more BE-4 engines.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 09/27/2017 04:28 AM
    Not the most effusive statement:

    Quote
    Meyerson: we have made “measurable progress” on BE-4 engine this year, with more engines in the pipeline. #IAC2017

    https://twitter.com/jeff_foust/status/912479192444420096 (https://twitter.com/jeff_foust/status/912479192444420096)

    In a follow-up tweet Jeff clarified it’s more BE-4 engines.
    It's like getting a "C+" on an elementary student's report card.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: sanman on 09/28/2017 10:44 PM
    Hasn't Blue been working on BE-4 longer than SpaceX has been working on Raptor?

    Who is closer to a finished engine right now?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: yokem55 on 09/28/2017 10:57 PM
    Hasn't Blue been working on BE-4 longer than SpaceX has been working on Raptor?

    Who is closer to a finished engine right now?
    At what size? SpaceX is already in all up testing for a 1MN engine but is likely a  couple years at least from the 3MN version. But Blue has a pretty good chance to be in all up testing at 2.4MN in the next year or so.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: russianhalo117 on 09/29/2017 02:08 AM
    Hasn't Blue been working on BE-4 longer than SpaceX has been working on Raptor?

    Who is closer to a finished engine right now?
    Raptor had been in testing at Stennis way before BE-4 and it wasn't even called Raptor when it started initial testing.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: jongoff on 09/29/2017 03:27 AM
    Hasn't Blue been working on BE-4 longer than SpaceX has been working on Raptor?

    Who is closer to a finished engine right now?

    They were pretty far along with BE-4 when ULA had them totally change the engine size (by almost 50%) to be compatible with what they needed for Vulcan. While they were able to leverage a lot of the earlier design work, it did force some redesigns and delays.

    ~Jon
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Nomic on 09/29/2017 08:55 AM
    As JoGoff points out BE-4 is a big engine, with Raptor seemingly down sized, BE-4 is the largest thrust chamber on a stage combustion engine since the ill fated RD-270. Apart from the size BE-4 is about as conservative as possible for an ORSC engine, low chamber pressure, when they where still doing update looked like its coxial swirl injector elements at least on the preburner. From SG1962 excellent commentary above it looks like they thought cfd modelling and component test they could avoid combustion instability and nasty transients, but they are finding the modelling doesn't correlate with reality at full scale.

    The whole decision to go with ORSC leaves me puzzled, obviously it leaves a lot of room for iterative improvements, but ULAs big customer is national security payloads, who normally aren't to keen on that kind of thing, but suppose they might have more oversight in this case.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: ChaoticFlounder on 09/30/2017 01:17 AM
    has anyone seen anymore details on the BE-4 engine following the IAC conference, the information faucet seems to be just barely dripping right now...  :'(
    Title: Re: Blue Origin's BE-4 Engine
    Post by: StvB on 10/05/2017 01:59 AM
    Have we seen this picture yet? Looks like an engine without a powerpack

    (https://g.foolcdn.com/editorial/images/458165/3-be-4-engines-is-blue-origin_large.jpg)

    edit: came from an article on this website: https://www.fool.com/investing/2017/10/04/jeff-bezos-has-3-customers-at-blue-origin-now-he-j.aspx (https://www.fool.com/investing/2017/10/04/jeff-bezos-has-3-customers-at-blue-origin-now-he-j.aspx)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: catdlr on 10/05/2017 02:42 AM
    Have we seen this picture yet? Looks like an engine without a powerpack

    (https://g.foolcdn.com/editorial/images/458165/3-be-4-engines-is-blue-origin_large.jpg)

    edit: came from an article on this website: https://www.fool.com/investing/2017/10/04/jeff-bezos-has-3-customers-at-blue-origin-now-he-j.aspx (https://www.fool.com/investing/2017/10/04/jeff-bezos-has-3-customers-at-blue-origin-now-he-j.aspx)

    Original source BY ALAN BOYLE on June 26, 2017: Geekwire.com:  https://www.geekwire.com/2017/jeff-bezos-blue-origin-picks-huntsville-alabama-rocket-city-4-engine/
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Kabloona on 10/06/2017 02:57 AM
    has anyone seen anymore details on the BE-4 engine following the IAC conference, the information faucet seems to be just barely dripping right now...  :'(

    This hardly qualifies as "details," but here it is anyway, a tweet from Jeff Foust quoting Bob Smith of Blue Origin at the National Space Council:

    Quote
    Jeff Foust‏
    @jeff_foust
    Smith: “soon” begin testing of BE-4 engine [after testing mishap earlier this year]

    https://twitter.com/jeff_foust/status/915959558203478016
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 10/06/2017 03:10 AM
    Better late than never.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Rik ISS-fan on 10/17/2017 07:21 AM
    The test stand on the image is for the BE-3 engines.
    The BE-4 test stand is located here (https://www.google.nl/maps/@31.43,-104.72,500m/data=!3m1!1e3) 31.43 ; -104.72
    Title: Re: Blue Origin's BE-4 Engine
    Post by: pstephens on 10/19/2017 07:30 PM
    Quote
    First hotfire of our BE-4 engine is a success #GradatimFerociter

    https://twitter.com/blueorigin/status/921095318669873154 (https://twitter.com/blueorigin/status/921095318669873154)

    Edit: Added screen grab
    Title: Re: Blue Origin's BE-4 Engine
    Post by: tvg98 on 10/19/2017 07:35 PM
    According to Eric Berger, it was fired at 50% thrust for about three seconds.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: envy887 on 10/19/2017 07:36 PM
    Quote
    First hotfire of our BE-4 engine is a success #GradatimFerociter

    https://twitter.com/blueorigin/status/921095318669873154 (https://twitter.com/blueorigin/status/921095318669873154)

    Excellent news :)

    I think that is the nail in the already mostly-closed coffin for AR-1.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: FutureSpaceTourist on 10/19/2017 07:55 PM
    Here’s the video
    Title: Re: Blue Origin's BE-4 Engine
    Post by: FutureSpaceTourist on 10/19/2017 08:03 PM
    Eric Berger’s write-up:

    https://arstechnica.com/science/2017/10/blue-origin-has-successfully-tested-its-powerful-be-4-rocket-engine/ (https://arstechnica.com/science/2017/10/blue-origin-has-successfully-tested-its-powerful-be-4-rocket-engine/)

    Quote
    Blue Origin just sent a jolt through the aerospace industry
    "As Joe Biden would say, this is a BFD for the space industry."

    by Eric Berger - Oct 19, 2017 8:31pm BS

    Edit to add:

    Quote
    The significance of Blue Origin's successful engine test is pretty simple. The company basically built a huge new engine with private money.
    https://twitter.com/sciguyspace/status/921098453698121732

    Quote
    The main line of attack from its legacy competitor was that this new company didn't have the experience to build such a large engine.
    https://twitter.com/sciguyspace/status/921098607436226560

    Quote
    Well, they just took a huge step toward putting the lie to that. Seven years of hard work, and now they're on fire. Like, literally.
    https://twitter.com/sciguyspace/status/921098909090430976
    Title: Blue Origin's BE-4 Engine
    Post by: Star One on 10/19/2017 09:04 PM
    Quote
    Tory Bruno
    @torybruno
    Congratulations

    https://mobile.twitter.com/torybruno/status/921116281641885696 (https://mobile.twitter.com/torybruno/status/921116281641885696)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: abaddon on 10/19/2017 09:06 PM
    Congratulations to Blue Origin, this is a huge step forward for the BE-4 program!
    Title: Re: Blue Origin's BE-4 Engine
    Post by: wannamoonbase on 10/19/2017 10:38 PM
    Congratulations Blue.

    Now lets see how it goes and how long it takes. 

    Long way to go, but this is a huge step for the American space industry.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: mnelson on 10/19/2017 10:41 PM
    Eric Berger’s write-up:

    https://arstechnica.com/science/2017/10/blue-origin-has-successfully-tested-its-powerful-be-4-rocket-engine/ (https://arstechnica.com/science/2017/10/blue-origin-has-successfully-tested-its-powerful-be-4-rocket-engine/)

    I sure love the fact that you can't write an article about the BE-4 without mentioning the Raptor nor about the Raptor and not mention the BE-4. A little friendly competition is a beautiful thing. It helps prevent lethargy.

    Of course, I don't think there is any real competition here. They are different engines being built for different uses. But still, most people run faster if there is someone running beside them. I know I do.  :)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: sanman on 10/19/2017 10:58 PM
    How long before it's tested at full thrust?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: TrevorMonty on 10/19/2017 11:01 PM
    Congratulations.Excellent start, a first firing that doesn't involve RUD.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 10/20/2017 12:27 AM
    Looks like a good, stable burn. Few artifacts, and more than enough to begin a considerable test program. Impressive even at 50% power. It wouldn't surprise if this engine surpasses RD-191 before the end of this year, and reaches 3MN before the next year is out.

    Congratulations to the Blue engine team! You look like you are on the way to orbit with a fine engine that can get you there.

    Tory Bruno, your hunch and going out on a limb looks like it will pay off after all. Now you have to work with Blue to get to a proven engine for Vulcan. Perhaps a nice Christmas gift is in the offing?

     
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Rik ISS-fan on 10/20/2017 11:22 AM
    Congratz Blue Origin and ULA, keep the good work going.
    Very good base for both expendable and reusable launchers.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: LouScheffer on 10/20/2017 12:39 PM
    This is a very good sign overall.  Although Russia for years has treated OSRC as a technology, elsewhere it's been regarded as a black art that requires some special secret sauce.  Now two additional independent groups are taking it seriously and bring it to production.   So soon there will be designers who understand the cycle, materials that are up to the job, and in general an ecosystem of all that is needed to make such a cycle work.   That's good for others who might want to improve their rockets as well (ESA?  Japan?  India?).   I'm sure ITAR will slow this down, but the more people who know how it's done, the faster the knowledge will spread, and everyone's rockets will get better.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: AncientU on 10/20/2017 12:44 PM
    Congrats Blue Team!

    Competition is a wonderful thing.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: abaddon on 10/20/2017 02:25 PM
    A good reminder that this is only the beginning.  AR-1 will only hang around as long as the US Air Force wants it to hang around, but it seems to me a good idea to wait to shelve it until BE-4 has not only hit that full thrust mark, but racked up some serious firing time.  RS-68A demonstrated 4,800 cumulative seconds on one test engine, for example.  Its predecessor RS-68 took three years from first hot fire to flight certification.

     - Ed Kyle
    That's all true; however, ULA has indicated it intends to down-select by the end of the year, and it seems a foregone conclusion that they will select the BE-4 at this point.  Once that happens they will move forward with vehicle design decisions that would not suit a rocket designed around the AR-1.  So the cost (and delay) to switch to an AR-1 will go up progressively from then.  This makes the benefit of keeping the development of AR-1 going much further seem to be rather low, barring some unanticipated new rocket that chooses to use the engine.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: PahTo on 10/20/2017 02:52 PM

    Fantastic!  I was at the Kent facility the day after the first fully integrated BE-4 shipped, and the excitement was (still) palpable.  Congrats to the teams--keep up the good work!
    Title: Re: Blue Origin's BE-4 Engine
    Post by: FutureSpaceTourist on 10/20/2017 02:55 PM
    Tweeted yesterday, I think stills from the video:

    Quote
    Blue Origin just shared some photos of the BE-4 hot fire test. 🔥 🔥

    https://twitter.com/SciGuySpace/status/921136925024583680 (https://twitter.com/SciGuySpace/status/921136925024583680)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: wolfpack on 10/20/2017 03:16 PM
    Nice to see BE-4 sing after that little hiccup back in May!

    I'm beginning to think the first real "victim" of New Space is likely to be Aerojet.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: ZachF on 10/20/2017 04:23 PM
    Congrats to the Blue Origin team!
    Title: Re: Blue Origin's BE-4 Engine
    Post by: gongora on 10/20/2017 05:21 PM
    This is a Blue Origin thread, please stay on topic.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: envy887 on 10/20/2017 06:05 PM
    Looks like a good, stable burn. Few artifacts, and more than enough to begin a considerable test program. Impressive even at 50% power. It wouldn't surprise if this engine surpasses RD-191 before the end of this year, and reaches 3MN before the next year is out.

    Congratulations to the Blue engine team! You look like you are on the way to orbit with a fine engine that can get you there.

    Tory Bruno, your hunch and going out on a limb looks like it will pay off after all. Now you have to work with Blue to get to a proven engine for Vulcan. Perhaps a nice Christmas gift is in the offing?

    I though they were targeting 2.45 MN as operational thrust. Is 122% a standard margin? Will they try to take it higher?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: RDMM2081 on 10/20/2017 07:23 PM
    Very exciting to see and hear about the first test of this engine!  I have a second repository of excitement waiting to hear more about the success of this test (which is not immediately apparent to me from 3 seconds of video) or in place of that another longer test get soon!
    Title: Re: Blue Origin's BE-4 Engine
    Post by: sanman on 10/20/2017 11:13 PM
    Just embedding the video here for easier viewing:

    https://www.youtube.com/watch?v=AhiI08HzIM0
    Title: Re: Blue Origin's BE-4 Engine
    Post by: LouScheffer on 10/20/2017 11:53 PM
    [...]  it seems to me a good idea to wait to shelve it  [the AR-1] until BE-4 has not only hit that full thrust mark, but racked up some serious firing time.
    I'm not a rocket designer, but if I was ULA I'd find 10 seconds at full thrust pretty convincing, much more so than full duration at any lesser power setting.   Of course you need both, but at these power levels the engine should reach equilibrium pretty quickly.   Running at less than full power is no guarantee the engine will survive higher, more stressful, settings.   But if it runs for 10 seconds at full power, it should be more or less straightforward to make it run for 10 minutes.

    So if I was ULA, I'd ask BO to step power first, to find any design weaknesses, so I could make a quick decision.  Then they can optimize for duration.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Patchouli on 10/21/2017 01:57 AM

    I wonder how close this is to a flight engine?
    Is it still using a heat sink nozzle or is it something close to the flight engine?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: SmallKing on 10/21/2017 06:05 AM

    I wonder how close this is to a flight engine?
    Is it still using a heat sink nozzle or is it something close to the flight engine?
    It can be a flight engine if they want it
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Step55 on 10/21/2017 07:22 AM

    I wonder how close this is to a flight engine?
    Is it still using a heat sink nozzle or is it something close to the flight engine?

    Is a heat-sink nozzle and a regenerative cooled nozzle not the same think?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: sanman on 10/21/2017 09:48 AM
    Is a heat-sink nozzle and a regenerative cooled nozzle not the same think?

    I thought the regeneratively cooled nozzle specifically has the fine channels to route the liquid propellant through, to cool the nozzle. Meanwhile the heat sink nozzle would simply have heat sink drawing off the heat, without particularly involving the propellant.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Patchouli on 10/21/2017 04:47 PM
    Is a heat-sink nozzle and a regenerative cooled nozzle not the same think?

    I thought the regeneratively cooled nozzle specifically has the fine channels to route the liquid propellant through, to cool the nozzle. Meanwhile the heat sink nozzle would simply have heat sink drawing off the heat, without particularly involving the propellant.
    Yes that's pretty much it.
    Sometimes test engines may use a heat sink nozzle when they're not being fired for very long.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 10/21/2017 05:39 PM
    Looks like a good, stable burn. Few artifacts, and more than enough to begin a considerable test program. Impressive even at 50% power. It wouldn't surprise if this engine surpasses RD-191 before the end of this year, and reaches 3MN before the next year is out.

    I though they were targeting 2.45 MN as operational thrust. Is 122% a standard margin? Will they try to take it higher?

    Yes - ULA needed considerably more thrust (and margin) than Blue was originally after, thus a larger engine and fewer for NG as a result. Would also expect that they are expecting to gradually increase chamber pressure beyond afterward.

    (The engine seems "over scaled" for  what they want/claim for it.)

    [...]  it seems to me a good idea to wait to shelve it  [the AR-1] until BE-4 has not only hit that full thrust mark, but racked up some serious firing time.
    I'm not a rocket designer, but if I was ULA I'd find 10 seconds at full thrust pretty convincing, much more so than full duration at any lesser power setting.   Of course you need both, but at these power levels the engine should reach equilibrium pretty quickly.   Running at less than full power is no guarantee the engine will survive higher, more stressful, settings.   But if it runs for 10 seconds at full power, it should be more or less straightforward to make it run for 10 minutes.

    So if I was ULA, I'd ask BO to step power first, to find any design weaknesses, so I could make a quick decision.  Then they can optimize for duration.

    Note we're not seeing start-up/shutdown, just the in between. Likely that's the big concern at the moment (also the big success!).

    So as they sequence/prove and increase stable mass flows/combustion with appropriate shutdown/tale off, then they'll look at wear patterns (OR), make changes, then go for more.

    A big concern is that an engine of this size have model-able operations, where the combustion is uniform and not chaotic. Less of a concern is the experience of the team, more of the concern is the nature of these propellants stable combustion during sequencing/cycle.

    You can meet your thrust/duration targets and still have an unacceptable operation of an engine. So it has to work fully, for the right reasons, repeatably ... for signoff.

    There were some good reasons for why it took so long with RS-68, but none of those are likely here. The two aren't comparable.

    From the artifacts present, suggest chamber pressure is the limiting factor in some form at the moment.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: zhangmdev on 10/21/2017 06:24 PM
    Does the portion of fuel passes through the regen-cooled nozzle also pass through the pre-burner?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Patchouli on 10/21/2017 07:12 PM


    Yes - ULA needed considerably more thrust (and margin) than Blue was originally after, thus a larger engine and fewer for NG as a result. Would also expect that they are expecting to gradually increase chamber pressure beyond afterward.

    (The engine seems "over scaled" for  what they want/claim for it.)


    I suspect they probably were originally aiming for 2X Merlin 1D thrust levels.


    Title: Re: Blue Origin's BE-4 Engine
    Post by: mnelson on 10/21/2017 11:20 PM


    Yes - ULA needed considerably more thrust (and margin) than Blue was originally after, thus a larger engine and fewer for NG as a result. Would also expect that they are expecting to gradually increase chamber pressure beyond afterward.

    (The engine seems "over scaled" for  what they want/claim for it.)


    I suspect they probably were originally aiming for 2X Merlin 1D thrust levels.

    Why would Merlin thrust levels be relevant when setting BE-4 goals?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Patchouli on 10/22/2017 12:23 AM


    Yes - ULA needed considerably more thrust (and margin) than Blue was originally after, thus a larger engine and fewer for NG as a result. Would also expect that they are expecting to gradually increase chamber pressure beyond afterward.

    (The engine seems "over scaled" for  what they want/claim for it.)


    I suspect they probably were originally aiming for 2X Merlin 1D thrust levels.

    Why would Merlin thrust levels be relevant when setting BE-4 goals?

    I mostly used it for comparison  but I suspect their original goal was 1,500 kN  to 2,000 kN.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: ChaoticFlounder on 10/22/2017 09:31 PM
    does anyone know if they've released more information on it?

    Do we know what they changed to make this engine go boom how it's supposed to?

    C
    Title: Re: Blue Origin's BE-4 Engine
    Post by: envy887 on 10/23/2017 06:49 PM
    Looks like a good, stable burn. Few artifacts, and more than enough to begin a considerable test program. Impressive even at 50% power. It wouldn't surprise if this engine surpasses RD-191 before the end of this year, and reaches 3MN before the next year is out.

    I though they were targeting 2.45 MN as operational thrust. Is 122% a standard margin? Will they try to take it higher?

    Yes - ULA needed considerably more thrust (and margin) than Blue was originally after, thus a larger engine and fewer for NG as a result. Would also expect that they are expecting to gradually increase chamber pressure beyond afterward.

    (The engine seems "over scaled" for  what they want/claim for it.)

    Blue was originally targeting 400 klbf (1800 kN). They upped it to 550 klbf (2450 kN) to sell it to ULA. Why would they need to fire it at 675 klbf (3000 kN)?

    Agree that it does seem oversized for 2450 kN and Blue is probably reserving performance.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Katana on 10/25/2017 01:46 PM
    Does the portion of fuel passes through the regen-cooled nozzle also pass through the pre-burner?
    Usually yes.
    Preburner have a separated small kick pump for higher pressure beyond main fuel flow.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: ZachF on 10/25/2017 04:24 PM
    Looks like a good, stable burn. Few artifacts, and more than enough to begin a considerable test program. Impressive even at 50% power. It wouldn't surprise if this engine surpasses RD-191 before the end of this year, and reaches 3MN before the next year is out.

    I though they were targeting 2.45 MN as operational thrust. Is 122% a standard margin? Will they try to take it higher?

    Yes - ULA needed considerably more thrust (and margin) than Blue was originally after, thus a larger engine and fewer for NG as a result. Would also expect that they are expecting to gradually increase chamber pressure beyond afterward.

    (The engine seems "over scaled" for  what they want/claim for it.)

    Blue was originally targeting 400 klbf (1800 kN). They upped it to 550 klbf (2450 kN) to sell it to ULA. Why would they need to fire it at 675 klbf (3000 kN)?

    Agree that it does seem oversized for 2450 kN and Blue is probably reserving performance.

    This engine does seem to have lots of upgrade potential just like the old Merlin.

    Upgrading to ~200bar in a future model would have thrust in the 3.7MN range...  :o
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 10/25/2017 06:09 PM
    Looks like a good, stable burn. Few artifacts, and more than enough to begin a considerable test program. Impressive even at 50% power. It wouldn't surprise if this engine surpasses RD-191 before the end of this year, and reaches 3MN before the next year is out.

    I though they were targeting 2.45 MN as operational thrust. Is 122% a standard margin? Will they try to take it higher?

    Yes - ULA needed considerably more thrust (and margin) than Blue was originally after, thus a larger engine and fewer for NG as a result. Would also expect that they are expecting to gradually increase chamber pressure beyond afterward.

    (The engine seems "over scaled" for  what they want/claim for it.)

    Blue was originally targeting 400 klbf (1800 kN). They upped it to 550 klbf (2450 kN) to sell it to ULA. Why would they need to fire it at 675 klbf (3000 kN)?

    Agree that it does seem oversized for 2450 kN and Blue is probably reserving performance.

    This engine does seem to have lots of upgrade potential just like the old Merlin.

    Upgrading to ~200bar in a future model would have thrust in the 3.7MN range...  :o
    Keep in mind that comparing a gas generator to ORSC, especially at this scale, isn't wise ...

    History of Russian kerolox ORSC shows that raising chamber pressure isn't at all that rapid as Merlin 1's progression, by a 5-6x factor. Also, likelihood for "big booms" (perhaps like what delayed first firing) is extremely high.

    There are a lot of reasons for this.

    That said, suggest that the overwhelming direction for this engine team is "operational", not pushing to extremes (suggest Raptor is attempting exactly *this*). In fact they went out of their way in design to downplay chamber pressure to expedite this engine. So expect no more than 3MN peak for quite a while.

    What instead -  large number of runs, considerable duration, multiple hardware sets under test concurrently, varying conditions of test runs. They want a six sigma matchup to prove no surprises and all conditions covered with significant operating data. And that's a ton of work in a short amount of time, all of it dangerous.

    Doing anything more would be sub-optimal.
    Title: Blue Origin's BE-4 Engine
    Post by: Star One on 10/25/2017 07:59 PM
    Quote
    Jeff Foust
    @jeff_foust
    Gunderson: the first BE-4 test lasted as long as planned (although he didn’t say how long); team very excited. #vonbraun
    8:34 pm · 25 Oct 2017

    https://mobile.twitter.com/jeff_foust/status/923271615307309056
    Title: Re: Blue Origin's BE-4 Engine
    Post by: ChaoticFlounder on 10/26/2017 01:39 AM
    [...]  it seems to me a good idea to wait to shelve it  [the AR-1] until BE-4 has not only hit that full thrust mark, but racked up some serious firing time.
    I'm not a rocket designer, but if I was ULA I'd find 10 seconds at full thrust pretty convincing, much more so than full duration at any lesser power setting.   Of course you need both, but at these power levels the engine should reach equilibrium pretty quickly.   Running at less than full power is no guarantee the engine will survive higher, more stressful, settings.   But if it runs for 10 seconds at full power, it should be more or less straightforward to make it run for 10 minutes.

    So if I was ULA, I'd ask BO to step power first, to find any design weaknesses, so I could make a quick decision.  Then they can optimize for duration.

    The largest concern for them is combustion instability which I don't believe we have been able to completely model yet.  As an outsider looking in the stresses are fairly well understood and predictable, it's the fluid flow and combustion that poses the real challenge.

    Reference NASA SP-194 to get a better understanding of the scale of what I'm talking about.

    As always, ask if you have questions or need a better explanation.

    C
    Title: Re: Blue Origin's BE-4 Engine
    Post by: sanman on 10/27/2017 11:50 PM
    Quote
    Jeff Foust
    @jeff_foust
    Gunderson: the first BE-4 test lasted as long as planned (although he didn’t say how long); team very excited. #vonbraun
    8:34 pm · 25 Oct 2017

    https://mobile.twitter.com/jeff_foust/status/923271615307309056

    What's the reference to #VonBraun - is this part of the nomenclature like Shepard, Glenn, Armstrong?
    What's it specifically referring to?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Zardar on 10/28/2017 12:04 AM
    Quote
    Jeff Foust
    @jeff_foust
    Gunderson: the first BE-4 test lasted as long as planned (although he didn’t say how long); team very excited. #vonbraun
    8:34 pm · 25 Oct 2017

    https://mobile.twitter.com/jeff_foust/status/923271615307309056

    What's the reference to #VonBraun - is this part of the nomenclature like Shepard, Glenn, Armstrong?
    What's it specifically referring to?

    "The Wernher von Braun Memorial Symposium is an annual event that features panel discussions and guest speakers reflecting government, industry, academia, business and international perspectives on space exploration."

    http://astronautical.org/events/vonbraun/ (http://astronautical.org/events/vonbraun/)
    https://www.facebook.com/AmericanAstronauticalSociety/ (https://www.facebook.com/AmericanAstronauticalSociety/)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Steven Pietrobon on 10/31/2017 02:12 AM
    Aviation Week article on the recent test.

    http://aviationweek.com/space/blue-origin-fires-be-4-methane-fuel-rocket-engine

    Not much new information. They did say they found the problem with the power pack failure and that it has been fixed. No information on what the failure is though.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: john smith 19 on 11/03/2017 03:24 PM
    There were some good reasons for why it took so long with RS-68, but none of those are likely here. The two aren't comparable.

    From the artifacts present, suggest chamber pressure is the limiting factor in some form at the moment.
    Wasn't RS68 the ablative cooled GG cycle LH2/LO2 for the Delta IV?

    I'd guess ablative reuse would have been an issue.

    Do you mean RS25, the SSME. There were 13 RUDs (of various levels of seriousness) getting it to flight. AFAIK It's still the only cryogenic SC (of any variant) to be developed in the US (before Blue and SX).
    Title: Re: Blue Origin's BE-4 Engine
    Post by: russianhalo117 on 11/03/2017 03:46 PM
    There were some good reasons for why it took so long with RS-68, but none of those are likely here. The two aren't comparable.

    From the artifacts present, suggest chamber pressure is the limiting factor in some form at the moment.
    Wasn't RS68 the ablative cooled GG cycle LH2/LO2 for the Delta IV?

    I'd guess ablative reuse would have been an issue.

    Do you mean RS25, the SSME. There were 13 RUDs (of various levels of seriousness) getting it to flight. AFAIK It's still the only cryogenic SC (of any variant) to be developed in the US (before Blue and SX).
    RS-68B LRE Upgrade with regenerative cooling was shelved after i believe the Critical Design Review because Constellation program was terminated and there wasn't another rocket that needed it because it was easier to take certain components of RS-68 to make an RS-25E. This has been discussed many times and doesn't need to be repeated again.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: john smith 19 on 11/03/2017 09:24 PM
    There were some good reasons for why it took so long with RS-68, but none of those are likely here. The two aren't comparable.

    From the artifacts present, suggest chamber pressure is the limiting factor in some form at the moment.
    Wasn't RS68 the ablative cooled GG cycle LH2/LO2 for the Delta IV?

    I'd guess ablative reuse would have been an issue.

    Do you mean RS25, the SSME. There were 13 RUDs (of various levels of seriousness) getting it to flight. AFAIK It's still the only cryogenic SC (of any variant) to be developed in the US (before Blue and SX).
    RS-68B LRE Upgrade with regenerative cooling was shelved after i believe the Critical Design Review because Constellation program was terminated and there wasn't another rocket that needed it because it was easier to take certain components of RS-68 to make an RS-25E. This has been discussed many times and doesn't need to be repeated again.
    Whenever I think of human rated engines canabalized from non human rated engines I think of the J-2X, with most parts from the RS68 or the RL10.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Robotbeat on 11/05/2017 12:29 AM
    Define "human rated" in a way that isn't 1) talking about an entire system (i.e. launch vehicle) or 2) cargo cult nonsense.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Raptor 42 on 11/13/2017 12:22 PM
    On the Blue Origin website it says that "allows for the removal of a solid rocket motor at more than $10 million per flight for comparable missions."
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Nilof on 11/20/2017 12:17 AM
    Define "human rated" in a way that isn't 1) talking about an entire system (i.e. launch vehicle) or 2) cargo cult nonsense.

    "Does not undergo RUD's on a significant fraction of engine tests" sounds like a good start.

    Above that, it depends on the exact level of safety you want, and on reusable engines there's also an element of how practical achieving that safety is. The RS-25 is a great example of an engine that was human rated and never had a failure on manned flight, but only with very expensive maintenance between flights.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: FutureSpaceTourist on 11/21/2017 01:39 PM
    Some good news for BE-4 funding in the recent NDAA:

    Good article by Eric Berger on the NDAA funding language and thus the flexibility it does, and does not, give the USAF:

    https://arstechnica.com/science/2017/11/a-new-law-gives-air-force-some-wiggle-room-in-picking-its-new-rockets/ (https://arstechnica.com/science/2017/11/a-new-law-gives-air-force-some-wiggle-room-in-picking-its-new-rockets/)

    Two crucial quotes:

    Quote
    Further, the bill defines “rocket propulsion system” as a main booster, first-stage rocket engine, or motor. The term does not include a launch vehicle, an upper stage, a strap-on motor, or related infrastructure.

    Quote
    Another provision in the bill relates to the engines under development for Vulcan. This language states that the Air Force may terminate funding for other rocket propulsion systems when “the Secretary of the Air Force certifies to the congressional defense committees that a successful full-scale test of a domestic rocket engine has occurred.”

    So first stage funding is fine, but not second or other stages, and AR-1 funding can be dropped once BE-4 achieves a 'full-scale test'.

    Best follow-up in the original (space policy) thread.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: FutureSpaceTourist on 01/08/2018 01:04 PM
    Quote
    Latest BE-4 engine test footage where we exceeded our Isp targets. We continue to exercise the deep throttling of our full scale 550,000 lbf BE-4, the reusability of our hydrostatic pump bearings and our stable start/stop cycles. More to follow from ongoing tests. #BE4 #NewGlenn

    https://twitter.com/blueorigin/status/950365085091811330 (https://twitter.com/blueorigin/status/950365085091811330)

    Vid to follow

    Edit: video now attached
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Davidthefat on 01/08/2018 02:16 PM
    Did a thermocouple or something get blasted off during shutdown? (Black wire looking thing flying around in the bell)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 01/08/2018 03:21 PM
    Nice progress to see Blue!

    You can see clear improvements across all aspects of engine operation visible.

    (One of the later things to see with such an engine will be be long duration tests, don't expect them soon.)

    As to ULA, I'd think that combustion stability with many repeatable runs with varying conditions is helpful to the decision to down select on engines. From what's shown, looks likely we'll hear an announcement in 1-2 months to go ahead with BE-4 on Vulcan.

    (Also, suspect that relentless pursuit of reliability and performance of this in successive video's we'll eventually see will become a hallmark of this engine. And while Vulcan will get the economical, performant engine it needs, it won't stop there - they'll give the Energomash designs a run for the money and then some.)

    Nice news.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: TrevorMonty on 01/08/2018 03:56 PM
    Have they done full power test yet? Even for few seconds.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 01/08/2018 04:08 PM
    Have they done full power test yet? Even for few seconds.
    Probably not.

    That wouldn't be a priority right now, and likely not useful. From the data accumulated, likely they can tell the bounds of engine performance they can reach.

    Most important is that they determine that the engine operates like expected/model, through various conditions. Plenty to do for that.

    There's many concurrent issues before you treat a propulsion system like it might be used on a LV. For you want it to work for the right reasons, not just any reason, for it to be a reliable/proven system that you need.

    This is the right amount of progress, in the right way.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: AncientU on 01/08/2018 04:24 PM
    Nice progress to see Blue!

    You can see clear improvements across all aspects of engine operation visible.

    ...

    Can you describe the 'improvements' that you see?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Davidthefat on 01/08/2018 04:39 PM
    Nice progress to see Blue!

    You can see clear improvements across all aspects of engine operation visible.

    ...

    Can you describe the 'improvements' that you see?

    Not blowing up? Wasn't there a breach in the power pack in the previously released information on testing?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: PahTo on 01/08/2018 04:54 PM
    Have they done full power test yet? Even for few seconds.
    Probably not.

    That wouldn't be a priority right now, and likely not useful. From the data accumulated, likely they can tell the bounds of engine performance they can reach.

    Most important is that they determine that the engine operates like expected/model, through various conditions. Plenty to do for that.

    There's many concurrent issues before you treat a propulsion system like it might be used on a LV. For you want it to work for the right reasons, not just any reason, for it to be a reliable/proven system that you need.

    This is the right amount of progress, in the right way.

    Thanks SG1962.  I asked the below in a Vulcan thread some time ago, and you've essentially answered here...

    "Also, what is the expected frequency of tests for the BE-4?  Given the "recent" 50% test, should we expect a "long duration"at 50%?  Short run at 100%?"
    Title: Re: Blue Origin's BE-4 Engine
    Post by: meberbs on 01/08/2018 05:07 PM
    Nice progress to see Blue!

    You can see clear improvements across all aspects of engine operation visible.

    ...

    Can you describe the 'improvements' that you see?

    Not blowing up? Wasn't there a breach in the power pack in the previously released information on testing?
    No, that was last spring and before they put a full scale engine on a stand.

    They released a previous video of a firing back in October, and they have been continuing to do tests since then. This is the second public video of a test of the full engine.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Chris Bergin on 01/08/2018 07:49 PM
    Short article to mark these tests:
    https://www.nasaspaceflight.com/2018/01/blue-origin-be-4-engine-testing/
    Title: Re: Blue Origin's BE-4 Engine
    Post by: jpo234 on 01/08/2018 08:28 PM
    Short article to mark these tests:
    https://www.nasaspaceflight.com/2018/01/blue-origin-be-4-engine-testing/

    Quote
    a gigantic production facility nearly competition on Merritt Island.

    ...a gigantic production facility nearing completion on Merritt Island.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: theinternetftw on 01/08/2018 08:33 PM
    Short article to mark these tests:
    https://www.nasaspaceflight.com/2018/01/blue-origin-be-4-engine-testing/

    Quote from: Chris Bergin in said short article

    Interestingly, L2 information notes Blue Origin’s BE-3E engine is making progress in a trade study being conducted at NASA’s Marshall Space Flight Center (MSFC) for use on the Space Launch System’s Exploration Upper Stage (EUS).

    This option is competing against the current baseline of the RL-10 and an alternative MB-60 LOX-LH2 engine from Japan.

    Marking the tests, and throwing in just the slightest bit of eyebrow-raising and tree-shaking I see ;)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 01/08/2018 10:35 PM
    Nice progress to see Blue!

    You can see clear improvements across all aspects of engine operation visible.

    ...

    Can you describe the 'improvements' that you see?
    Compare the video's side by side.

    First is "trimmed" so you don't see start-up/shutdown. Second you do. Perhaps because both did not appear ideal?

    Second showed nothing but an appropriate start-up/shutdown for those absences.

    First has artifacts visible that show unreacted in flow (saps iSP) and irregular, lower thrust. Not visible in second.

    Second has some throttling and mach diamonds appearing well defined as changing. First was less defined and at a constant thrust level. Changing thrust on a LRE risks combustion instability. (Many LRE didn't have much/any throttle capability.)

    In short, the second appropriately characterizes what the BE-4 has been represented to be - a throttleable, restartable ORSC engine. Unlike the prior, which just showed it to be a LRE that can function as one.

    And, like with what the first showed of operation, all elements of the second including operation, show across the board effective improvement from the first.

    So what's missing? Duration, thrust levels, operating/starting/shutdown conditions, wear assessment, ... these come eventually.

    What they are telling us in this video is that they made the engine they told us they would and it works as designed.

    What they can't yet tell us is when it becomes a viable propulsion system for use by a LV.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: daveklingler on 01/09/2018 01:43 AM
    AFAIK It's still the only cryogenic SC (of any variant) to be developed in the US (before Blue and SX).

    No.  Pratt & Whitney developed a series of hydrolox high-pressure staged-combustion engines to airline engine reusability standards during the 1960's.

    According to the book, "Advanced Engine Development at Pratt and Whitney", credit for original invention of the staged combustion engine goes to John Chamberlain at P&W.  While studying ways to increase combustion chamber pressure on the RL-10, Chamberlain thought of burning a little oxygen in the hydrogen working fluid before the turbine. They began testing the concept successfully in 1960.

    P&W went on to develop a series of hydrolox staged combustion engines for, or so they thought, the coming wave of NASA's reusable rockets.  Beginning in the late 1950's, P&W developed the 10K, 50K, RL20 (225Klbs thrust), 250K and 350K engines to airline-standards of reusability. Along the way, Chamberlain also invented transpiration cooling for rocket engines, and by mid-1963, the 10K chamber was up to 3300 PSI.  The 5600 psi turbopumps for the 350K engine were complete by mid-1967, and they reached 6700 PSI for the 250K engine's turbopump.

    All of these engines were developed for essentially unlimited reusability in reusable space transports over a little over a decade with a view toward the SSME. Despite the fact that they had never done any work in high-pressure reusable staged-combustion engines, Rocketdyne was given the contract for the SSME anyway and P&W was forced to send Rocketdyne their development notes.  P&W was later asked by NASA to return and make the SSME work and ended up working on it quietly through the end of the Shuttle program.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Chasm on 01/09/2018 03:45 AM

    Quote from: Chris Bergin in said short article

    Interestingly, L2 information notes Blue Origin’s BE-3E engine is making progress in a trade study being conducted at NASA’s Marshall Space Flight Center (MSFC) for use on the Space Launch System’s Exploration Upper Stage (EUS).

    Marking the tests, and throwing in just the slightest bit of eyebrow-raising and tree-shaking I see ;)

    Yes, what is the BE-3E. Previously we only heard about the BE-3U being worked on.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Lars-J on 01/09/2018 03:51 AM

    Quote from: Chris Bergin in said short article

    Interestingly, L2 information notes Blue Origin’s BE-3E engine is making progress in a trade study being conducted at NASA’s Marshall Space Flight Center (MSFC) for use on the Space Launch System’s Exploration Upper Stage (EUS).

    Marking the tests, and throwing in just the slightest bit of eyebrow-raising and tree-shaking I see ;)

    Yes, what is the BE-3E. Previously we only heard about the BE-3U being worked on.

    They are the same engine. (or it is a very close cousin, like the RL-10 variants)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: J-V on 01/09/2018 06:11 AM
    Can anyone estimate from the mach diamonds in the new video what is the throttle range used in the test? I mean we don't know if the maximum used is 100% (probably not), but is the highest thrust e.g. 2x the minimum thrust used during the test?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Boost on 01/09/2018 11:09 PM
    All real booster engines are overexpanded at sea level, many have the exit pressure at about 0.6 atm. This improves overall performance during flight.
    Was it even the case for the Shuttle SRB ? They seem slightly underexpanded since liftoff.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Chasm on 01/10/2018 05:03 AM
    YT version of the BE-4 test video

    https://www.youtube.com/watch?v=ksGnkKeGy4I
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Chasm on 01/10/2018 05:09 AM
    Yes, what is the BE-3E. Previously we only heard about the BE-3U being worked on.

    They are the same engine. (or it is a very close cousin, like the RL-10 variants)

    Perhaps fixed vs extensible nozzle.
    Looking at the Orbital ATK articles again the contract was "for development of [...], and an extendable nozzle for Blue Origin's BE-3U/EN upper stage engine."
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Nilof on 01/10/2018 11:59 PM
    Maybe E for expendable, just like the upper stage it will be used on? Which would imply that Blue would be considering reuse for their own upper stage.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: silverthorne on 01/22/2018 04:46 PM
    Sorry if I missed this in the discussion earlier...

    Anyone know what the BE-4 nominal mixture ratio s supposed to be, compared to the Aerojet AR-1 (2.2?)?

    Wouldn't that have a definite impact on tank sizing?  If so, how can ULA be designing it's Vulcan booster stage, tanks and all, if it hasn't committed 100% to one engine?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: woods170 on 01/22/2018 04:50 PM
    Sorry if I missed this in the discussion earlier...

    Anyone know what the BE-4 nominal mixture ratio s supposed to be, compared to the Aerojet AR-1 (2.2?)?

    Wouldn't that have a definite impact on tank sizing?  If so, how can ULA be designing it's Vulcan booster stage, tanks and all, if it hasn't committed 100% to one engine?

    Easy. Double design, double CDR.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: silverthorne on 01/22/2018 04:55 PM
    From what I understand from friends I have at ULA, they are working towards a single CDR.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Ictogan on 01/22/2018 04:58 PM
    Sorry if I missed this in the discussion earlier...

    Anyone know what the BE-4 nominal mixture ratio s supposed to be, compared to the Aerojet AR-1 (2.2?)?

    Wouldn't that have a definite impact on tank sizing?  If so, how can ULA be designing it's Vulcan booster stage, tanks and all, if it hasn't committed 100% to one engine?
    Comparing mixture ratio is not really useful as they are using entirely different fuels, but that is already making designing Vulcan to be able to accept both engines impossible. Note that the diameter of Vulcan will also be different depending on which engine it ends up with(source (https://spaceflightnow.com/2017/04/18/ula-chief-says-blue-origin-in-drivers-seat-for-vulcan-engine-deal/)).

    My guess is that they have already decided on BE-4 internally, but want to keep the possibility of switching to the AR-1 just in case testing the engine to flight performance doesn't work out.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: mme on 01/22/2018 05:15 PM
    ...
    Wouldn't that have a definite impact on tank sizing?  If so, how can ULA be designing it's Vulcan booster stage, tanks and all, if it hasn't committed 100% to one engine?

    Easy. Double design, double CDR.
    Which is why I'm confused that ULA doesn't seem to be in a rush to down select.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: envy887 on 01/22/2018 05:24 PM
    ...
    Wouldn't that have a definite impact on tank sizing?  If so, how can ULA be designing it's Vulcan booster stage, tanks and all, if it hasn't committed 100% to one engine?

    Easy. Double design, double CDR.
    Which is why I'm confused that ULA doesn't seem to be in a rush to down select.

    Who says they haven't downselected? They don't have to announce it right away.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: mme on 01/22/2018 05:42 PM
    ...
    Which is why I'm confused that ULA doesn't seem to be in a rush to down select.

    Who says they haven't downselected? They don't have to announce it right away.
    True, I'm basing it on a recent tweet by Jeff Foust and an article from November.

    https://twitter.com/jeff_foust/status/954065403449364486 (https://twitter.com/jeff_foust/status/954065403449364486)
    Quote
    Jeff Foust‏
    @jeff_foust

    Tshudy: no downselect yet on Vulcan engine, but anticipate it “this year.”

    10:58 AM - 18 Jan 2018

    ULA feels no schedule pressure to select Vulcan engine[/ula] (http://spacenews.com/ula-feels-no-schedule-pressure-to-select-vulcan-engine/)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Electric Paint on 01/22/2018 07:39 PM
    Maybe E for expendable, just like the upper stage it will be used on? Which would imply that Blue would be considering reuse for their own upper stage.
    Or it may stand for "Exploration" as it is being considered for the Exploration Upper Stage. That may involve design specifications to accommodate longer loiter times than the BE-3U is designed for. I have seen recent images released by Bigelow on Instagram that suggest that they are considering the EUS as a propulsion block for their modular spacecraft designs.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: russianhalo117 on 01/22/2018 07:58 PM
    Maybe E for expendable, just like the upper stage it will be used on? Which would imply that Blue would be considering reuse for their own upper stage.
    Or it may stand for "Exploration" as it is being considered for the Exploration Upper Stage. That may involve design specifications to accommodate longer loiter times than the BE-3U is designed for. I have seen recent images released by Bigelow on Instagram that suggest that they are considering the EUS as a propulsion block for their modular spacecraft designs.
    BE-3E was originally known as BE-3U-EN (BE-3 Upper Stage - Extensible Nozzle)  BE-3E is similar to the deployable nozzle on an RL-10B-2 and RL-10C-2/C-3 but with greater thrust and throttle range unless AR CECE technology is rolled into an operational RL-10 or RL-60 engine class series.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Steven Pietrobon on 01/23/2018 04:20 AM
    Anyone know what the BE-4 nominal mixture ratio s supposed to be, compared to the Aerojet AR-1 (2.2?)?

    Blue has given very little technical information. The only thing we know is the thrust at 2447 kN (550 klbf). My expectation would be around 3.5:1 for a staged combustion methalox engine. The AR-1 is probably around 2.6:1 for a kerolox engine (RD-180 is 2.72:1).
    Title: Re: Blue Origin's BE-4 Engine
    Post by: woods170 on 01/23/2018 06:51 AM
    From what I understand from friends I have at ULA, they are working towards a single CDR.

    No, that is wrong. Tony Bruno reported via Twitter that CDR had begun. (https://twitter.com/torybruno/status/938594215235280896) That was well over a month ago.

    They haven't formally chosen an engine yet. And with it comes the choice of fuel. For BE-4 that is LNG and for AR-1 it is RP-1.

    The result is two different sets of requirements for mixture ratio, tankage volume, vehicle plumbing, GSE set-up, etc. etc. etc.

    What I suspect is that ULA has been designing the vehicle as "generic" as possible to make CDR, with specific components having been designed twice (for AR-1 vs BE-4).

    But once the engine choice has been made it is a safe bet that a series of delta-CDR's is coming to accommodate the design-changes, and final designs, resulting from the final engine-choice.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: brickmack on 01/23/2018 01:47 PM
    Or it may stand for "Exploration" as it is being considered for the Exploration Upper Stage. That may involve design specifications to accommodate longer loiter times than the BE-3U is designed for. I have seen recent images released by Bigelow on Instagram that suggest that they are considering the EUS as a propulsion block for their modular spacecraft designs.

    Thats an ACES, not EUS. If you missed the news, http://www.ulalaunch.com/bigelow-aerospace-and-ula-lunar-depot.aspx
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Sknowball on 01/23/2018 02:54 PM
    From what I understand from friends I have at ULA, they are working towards a single CDR.

    No, that is wrong. Tony Bruno reported via Twitter that CDR had begun. (https://twitter.com/torybruno/status/938594215235280896) That was well over a month ago.

    The latest information that has been provided is that their CDR is composed of two parts and that the first part was completed (https://twitter.com/torybruno/status/951271568218320896) last month.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Chasm on 01/23/2018 02:58 PM
    As far as I can tell ULA did only one PDR, and that was not for the AR-1 engine.
    Explicitly for the BE4, in the Vulcan (Common) Centaur configuration at the time.

    [ULA press release, March 2016 (http://www.ulalaunch.com/ula-completes-Vulcan-Centaur-PDR.aspx)]

    The introduction of Centaur V makes tracking the CDR(s) a bit more complex to track
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Navier–Stokes on 02/28/2018 09:34 PM
    Quote from: https://twitter.com/jeff_foust/status/968970651355709440
    Jeff Foust‏ @jeff_foust

    Jim Centore, Blue Origin: making good progress on BE-4 engine testing. Getting to longer duration [but unspecified] burn times, and multiple runs on the same engine. Continuing testing for the next several months.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 02/28/2018 09:46 PM
    Significance of multiple runs on same engine is that they have a) many units under test (reproducability) and b) some idea of wear on engine - critical for an ORSC that is vulnerable to significant erosion down stream of the preburner.

    They are about where the earlier schedules would have put them in the September/October time frame. Good progress.

    add:
    It is unlikely you'd attempt a high thrust test burn, before you have long duration burns.

    Long duration burns allow you to gain insight on combustion stability and thermal dissipation, in addition to obviously greater engine wear it must endure to get the duration. You determine margins and can tell thermal runaway that might happen at high thrust levels, as well as determining the chamber pressures that the engine will be operating at to obtain them.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: TrevorMonty on 03/01/2018 12:01 AM
    The question is have they done full thrust burn, even its for few seconds.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: AncientU on 03/01/2018 04:32 PM
    Quote from: https://twitter.com/jeff_foust/status/968970651355709440
    Jeff Foust‏ @jeff_foust

    Jim Centore, Blue Origin: making good progress on BE-4 engine testing. Getting to longer duration [but unspecified] burn times, and multiple runs on the same engine. Continuing testing for the next several months.

    Significance of multiple runs on same engine is that they have a) many units under test (reproducability) and b) some idea of wear on engine - critical for an ORSC that is vulnerable to significant erosion down stream of the preburner.

    They are about where the earlier schedules would have put them in the September/October time frame. Good progress.

    add:
    It is unlikely you'd attempt a high thrust test burn, before you have long duration burns.

    Long duration burns allow you to gain insight on combustion stability and thermal dissipation, in addition to obviously greater engine wear it must endure to get the duration. You determine margins and can tell thermal runaway that might happen at high thrust levels, as well as determining the chamber pressures that the engine will be operating at to obtain them.

    Not sure where the 'good progress' comes from other than the original quote.

    Parsing Jim Centore's statement:
    1. "Getting to longer duration..." is a double qualifier, "getting to" is current or near future status, while "longer duration" could mean three seconds to five, or ten, or even four.
    2. "Multiple runs on same engine" could mean two or three, hopefully five or ten...
    (one or more engines could only have one -- why?)
    3. "Continuing testing for next several months"... certainly.  There is a tonne of testing and flight qualification ahead, maybe a year or two, but why mention several months?  Does something special happen in several months?  ...new prototype engine(s)? ...full power/duration/other tests? ...down select by ULA?

    Remember that these engines are designed to be flown repeatedly on a reusable rocket, not just one and done on Vulcan.  They better not show any erosion or engine wear after a few short-duration, low power test runs.

    Jim Centore might have been spreading a success story and "good progress", but his language is so guarded as to be questionable about how good is "good" progress.  Maybe also the guarded company culture at Blue...

    Add:
    They are at the one year mark from roll-out of full scale engine.

    Ninja'd in updates thread:

    @JeffBezos  15m15 minutes ago

     1st BE-4 engine fully assembled. 2nd and 3rd following close behind. #GradatimFerociter

    @JeffBezos  11m11 minutes ago

     Here’s one more shot of BE-4 in its transport cradle.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Jim on 03/01/2018 05:33 PM
    How about applying the same critical eye to SpaceX and not just anything not SpaceX
    Title: Re: Blue Origin's BE-4 Engine
    Post by: TrevorMonty on 03/01/2018 05:43 PM
    How about applying the same critical eye to SpaceX and not just anything not SpaceX
    You are wasting you time Jim, SpaceX fans are one eyed.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Chris Bergin on 03/01/2018 05:49 PM
    (http://i0.kym-cdn.com/photos/images/original/000/353/279/e31.jpg)

    Everyone calm down and be civil. Thread title. Discuss topic. Carry on.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: envy887 on 03/01/2018 05:54 PM
    Foust is paraphrasing Centore, not quoting him, so a word by word analysis could be quite misleading.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 03/01/2018 06:04 PM
    How about applying the same critical eye to SpaceX and not just anything not SpaceX
    Absolutely. AncientU's post isn't fair, or based of understanding, or inquiring why.

    (Note - my post above was meant to synopsize success. Meant to "buffer" ignorant criticism with some insight, in an area one cannot "teach" in posts. Perhaps I shouldn't, if it's going to be used as a means to attack by rhetorically picking from it to concoct a negative.)

    SX took an expedient route (gas generator, combined ELV/RLV) with higher losses. BO takes a longer route (ORSC, RLV) attempting zero losses (two to date, high reuse on NS that SX hasn't ever had).

    You may disagree with choices but they are reasonable, respectable ones.

    Again, they have made good progress with BE-4, and I wish them well in hoping to hear more success in testing.

    add:
    It occurs to me that many here don't know why America avoided ORSC til now. The development rate is mostly dominated by "boom" and test stand rebuild. It is "good progress" when you don't get "boom" and "rebuild". This stuff is very hard, sometimes too hard.

    The Russians did a lot of "boom" "rebuild", and many thought that was a bad idea. But it got a fantastic engine in RD-180. If you are going to attempt to outdo them, and you avoid "boom" and "rebuild" ... that's world class.

    I have in the past chided them competitively given Raptor's FFSC success, but only because both teams (like all competitive teams) have an eye on the other - because competition is great for aerospace, not to run either down. And they can take it.

    add:

    And to put the shoe on the other foot, we've heard twice now on BE-4 testing, but nothing more on Raptor. Aren't we overdue on a SX report on how Raptor is doing? Unless it's sliding into "Musk time dilation"? By now they should have finished 1/3 scale Raptor tests, and be fabricating a full scale along with an test stand that can handle such. Hello? Where is it?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: PahTo on 03/01/2018 06:20 PM

    (Note - my post above was meant to synopsize success. Meant to "buffer" ignorant criticism with some insight, in an area one cannot "teach" in posts. Perhaps I shouldn't, if it's going to be used as a means to attack by rhetorically picking from it to concoct a negative.)

    Again, they have made good progress with BE-4, and I wish them well in hoping to hear more success in testing.


    No, you should (please) continue to provide insight--posts like yours are exactly what and why many of us have been (wow, in my case for more than a decade) and continue to be on NSF.

    Concur on the success-wishes, as testing leads to flight-ready production hardware.  Bring it on!
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Darkseraph on 03/01/2018 06:25 PM
    Quote
    More than six years into development
    BE-4 is already more than six years into development, fully funded, and will be flight qualified in 2018 – at least two years ahead of the alternative engine option. BE-4 component testing has already been underway for more than four years and full engine testing will begin soon.

    Ready in 2019
    BE-4 is the only engine that can fly by 2019, meeting the congressionally mandated deadline to eliminate dependence on Russian-built engines. The alternative engine option is multiple years behind and could not be integrated into a launch vehicle until at least 2021, extending our dependence on Russian engines well beyond 2019.
    from the horse's mouth (https://www.blueorigin.com/BE4)

    I presume "in the next couple of months" refers to the expectation it will be flight qualified by the end of 2018. Which seems credible given the full scale version has already hot fired multiple times and the engines has been in development for over six years. There will be delays just like everything else, but probably on the order of months, not years.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: AncientU on 03/01/2018 08:42 PM
    How about applying the same critical eye to SpaceX and not just anything not SpaceX
    Absolutely. AncientU's post isn't fair, or based of understanding, or inquiring why.

    (Note - my post above was meant to synopsize success. Meant to "buffer" ignorant criticism with some insight, in an area one cannot "teach" in posts. Perhaps I shouldn't, if it's going to be used as a means to attack by rhetorically picking from it to concoct a negative.)
    ...

    I, for one, appreciate Space Ghost's posts and detailed analyses across all topics.  Your insight plus generous contribution of time to explain context is a huge asset of NSF.

    On this particular topic and update from Jim Centore*, I was not hearing as positive a progress report on BE-4 as I was hoping for...  and searching for the downside of what was said.  Space Ghost took the quotes and stretched them on the upside, in my opinion, and I was probing the other possibility.  Critical eye?  Yes.  Bad-mouthing or slamming Blue -- 'a means to attack by rhetorically picking from it to concoct a negative' -- absolutely not my intention. 

    For the record, I'm fully supportive of Blue Origin as a valuable contributor to competition in the reusable rocket development effort, BE-4 as a critical part of that, and for New Glenn and its success.  Full disclosure: I care much less about whether Vulcan gets an engine in a timely manner, but do think the BE-4 is the only viable path to ending RD-180 purchases from Russia anywhere near 2022.

    For an American company to be making the ORSC engine that some claim impossible (textbooks, for instance) on their own dime is to be lauded.  For them to already have seven commercial orders for NG is fantastic.  None of this takes away from SpaceX -- it in fact helps to solidify the 'fantasy' that reusable rockets are the future.


    * By the way, Jeff Foust is usually bang-on when he 'paraphrases' -- more like direct quotes than most in the media.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: AncientU on 03/01/2018 09:39 PM
    Quote
    More than six years into development
    BE-4 is already more than six years into development, fully funded, and will be flight qualified in 2018 – at least two years ahead of the alternative engine option. BE-4 component testing has already been underway for more than four years and full engine testing will begin soon.

    Ready in 2019
    BE-4 is the only engine that can fly by 2019, meeting the congressionally mandated deadline to eliminate dependence on Russian-built engines. The alternative engine option is multiple years behind and could not be integrated into a launch vehicle until at least 2021, extending our dependence on Russian engines well beyond 2019.
    from the horse's mouth (https://www.blueorigin.com/BE4)

    I presume "in the next couple of months" refers to the expectation it will be flight qualified by the end of 2018. Which seems credible given the full scale version has already hot fired multiple times and the engines has been in development for over six years. There will be delays just like everything else, but probably on the order of months, not years.

    This Blue Origin web page information appears over a year old; Jim Centore's comments were today's status.

    The real question is when can this engine be flight qualified?  2018 was estimate as of over a year ago... is it still a viable target date?  We certainly did not get that confirmation from Mr. Centore's statement unless your interpretation of 'several months' is correct.  If he had news that they were a few months from a flight qualified engine, he'd have made a more substantial and positive statement.  As stated, it's more like they are still carefully searching the parameter space with their testing.

    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 03/01/2018 10:03 PM
    The real question is when can this engine be flight qualified?  2018 was estimate as of over a year ago... is it still a viable target date?
    Yes they can. It will be late. IMHO doubt 2020. Others will be late too, as before. So what.

    It's not a "design flaw" issue here. It's a gradual proving by "mm, degrees, milliseconds, ..." issue. Then some refinements.

    Wash. Rinse. Repeat. Just no "booms". Same is true for Raptor.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: AncientU on 03/01/2018 10:27 PM
    The real question is when can this engine be flight qualified?  2018 was estimate as of over a year ago... is it still a viable target date?
    Yes they can. It will be late. IMHO doubt 2020. Others will be late too, as before. So what.

    It's not a "design flaw" issue here. It's a gradual proving by "mm, degrees, milliseconds, ..." issue. Then some refinements.

    Wash. Rinse. Repeat. Just no "booms". Same is true for Raptor.

    I do think the engine will be flight qualified, as will the eventual full scale Raptor, booms or no.  Don't think having a failure, or a few failures, on the test stand is something negative, other than the delay involved.  Having zero would be nice, but not necessary.  Just need to press on...
    Title: Re: Blue Origin's BE-4 Engine
    Post by: rpapo on 03/01/2018 11:30 PM
    The only useless boom is the one you don't learn from.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 03/01/2018 11:38 PM
    The only useless boom is the one you don't learn from.
    Booms can destroy that which you need to learn from. Indiscriminate. Too easily.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: AncientU on 03/01/2018 11:39 PM
    ...

    add:

    And to put the shoe on the other foot, we've heard twice now on BE-4 testing, but nothing more on Raptor. Aren't we overdue on a SX report on how Raptor is doing? Unless it's sliding into "Musk time dilation"? By now they should have finished 1/3 scale Raptor tests, and be fabricating a full scale along with an test stand that can handle such. Hello? Where is it?

    Not like you to low value post...

    But, since you asked, I was wondering the same.

    We saw first raptor burn at IAC2016.
    Next we heard was at IAC 2017... 42 tests, 1,200s cumulative over the first year of testing.
    We've also heard testing continues this year.

    We may have to wait until IAC 2018 to get next quantitative status.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 03/01/2018 11:52 PM
    Been told to post less frequent/depth, be more crisp and balanced with inconsistent rivals, limiting details. Hard.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: woods170 on 03/02/2018 08:08 AM
    ...

    add:

    And to put the shoe on the other foot, we've heard twice now on BE-4 testing, but nothing more on Raptor. Aren't we overdue on a SX report on how Raptor is doing? Unless it's sliding into "Musk time dilation"? By now they should have finished 1/3 scale Raptor tests, and be fabricating a full scale along with an test stand that can handle such. Hello? Where is it?

    Not like you to low value post...

    But, since you asked, I was wondering the same.

    We saw first raptor burn at IAC2016.
    Next we heard was at IAC 2017... 42 tests, 1,200s cumulative over the first year of testing.
    We've also heard testing continues this year.

    We may have to wait until IAC 2018 to get next quantitative status.

    That would be correct. Both Raptor and BE-4 are new developments in the history of US-developed rocket engines. Informing their competitors, by issuing regular updates on testing, is the one thing SpaceX and Blue are not going to do.
    However, the fact that SpaceX and Blue remain silent on their progress does not mean that there is no progress.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: SDSmith on 03/02/2018 09:39 AM
    Been told to post less frequent/depth, be more crisp and balanced with inconsistent rivals, limiting details. Hard.
    When I see a large post from Space Ghost I look forward to reading it. It forces me to slow down and digest what is written. Sometimes the longer post is easier to write than a short concise message.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: RotoSequence on 03/02/2018 09:43 AM
    Been told to post less frequent/depth, be more crisp and balanced with inconsistent rivals, limiting details. Hard.

    I like a good long-form post better.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: AncientU on 03/02/2018 10:19 AM
    Been told to post less frequent/depth, be more crisp and balanced with inconsistent rivals, limiting details. Hard.

    Your analysis is a healthy feature of NSF.  It should not be curtailed, IMO, if you can afford the time to flesh out your ideas and provide insight to those of us who are interested observers without first-hand access.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: FinalFrontier on 03/02/2018 10:26 AM
    Been told to post less frequent/depth, be more crisp and balanced with inconsistent rivals, limiting details. Hard.
    We would prefer you post just as much as before please ignore whoever said that. 
    Title: Re: Blue Origin's BE-4 Engine
    Post by: FinalFrontier on 03/02/2018 10:29 AM
    Back on topic what I am interested in here. Have there been anymore failures of test engines or critical components on the test stand in individual tests?
    Do we have anymore idea what caused the failures we heard about in the past 18 months and if they designed it out?
    If they have had multiple successful firings on the same development engine now it probably means they solved it but if they aren't at full thrust it may be best not jinx it.

    Very curious to know what went wrong in the earlier tests.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Star One on 03/02/2018 10:37 AM
    ...

    add:

    And to put the shoe on the other foot, we've heard twice now on BE-4 testing, but nothing more on Raptor. Aren't we overdue on a SX report on how Raptor is doing? Unless it's sliding into "Musk time dilation"? By now they should have finished 1/3 scale Raptor tests, and be fabricating a full scale along with an test stand that can handle such. Hello? Where is it?

    Not like you to low value post...

    But, since you asked, I was wondering the same.

    We saw first raptor burn at IAC2016.
    Next we heard was at IAC 2017... 42 tests, 1,200s cumulative over the first year of testing.
    We've also heard testing continues this year.

    We may have to wait until IAC 2018 to get next quantitative status.

    Can I ask you a very simple question why do you think you’re entitled to know anything at this stage in the development of the BE-4?

    In my opinion Blue Origin don’t owe anyone outside of themselves, their relevant commercial partners and the USAF in the case of Vulcan anything information wise on the progression of the BE-4.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: AncientU on 03/02/2018 12:22 PM
    ...

    add:

    And to put the shoe on the other foot, we've heard twice now on BE-4 testing, but nothing more on Raptor. Aren't we overdue on a SX report on how Raptor is doing? Unless it's sliding into "Musk time dilation"? By now they should have finished 1/3 scale Raptor tests, and be fabricating a full scale along with an test stand that can handle such. Hello? Where is it?

    Not like you to low value post...

    But, since you asked, I was wondering the same.

    We saw first raptor burn at IAC2016.
    Next we heard was at IAC 2017... 42 tests, 1,200s cumulative over the first year of testing.
    We've also heard testing continues this year.

    We may have to wait until IAC 2018 to get next quantitative status.

    Can I ask you a very simple question why do you think you’re entitled to know anything at this stage in the development of the BE-4?

    In my opinion Blue Origin don’t owe anyone outside of themselves, their relevant commercial partners and the USAF in the case of Vulcan anything information wise on the progression of the BE-4.

    I've never said or implied that I or anyone else is entitled* to this information. 
    What's your source of this snark?

    * Doesn't mean we aren't interested and ready to grab any bits that fall to the floor.
    Title: Blue Origin's BE-4 Engine
    Post by: Star One on 03/02/2018 01:09 PM
    ...

    add:

    And to put the shoe on the other foot, we've heard twice now on BE-4 testing, but nothing more on Raptor. Aren't we overdue on a SX report on how Raptor is doing? Unless it's sliding into "Musk time dilation"? By now they should have finished 1/3 scale Raptor tests, and be fabricating a full scale along with an test stand that can handle such. Hello? Where is it?

    Not like you to low value post...

    But, since you asked, I was wondering the same.

    We saw first raptor burn at IAC2016.
    Next we heard was at IAC 2017... 42 tests, 1,200s cumulative over the first year of testing.
    We've also heard testing continues this year.

    We may have to wait until IAC 2018 to get next quantitative status.

    Can I ask you a very simple question why do you think you’re entitled to know anything at this stage in the development of the BE-4?

    In my opinion Blue Origin don’t owe anyone outside of themselves, their relevant commercial partners and the USAF in the case of Vulcan anything information wise on the progression of the BE-4.

    I've never said or implied that I or anyone else is entitled* to this information. 
    What's your source of this snark?

    * Doesn't mean we aren't interested and ready to grab any bits that fall to the floor.

    The source of my so called snark is the seeming expectation for all commercial companies in this sector to act in the same PR led way that Space X does. Leading by PR often leads to things like hyperbole and unrealistic delivery dates for products. Maybe in this case less is more?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Davidthefat on 03/02/2018 01:43 PM
    ...

    add:

    And to put the shoe on the other foot, we've heard twice now on BE-4 testing, but nothing more on Raptor. Aren't we overdue on a SX report on how Raptor is doing? Unless it's sliding into "Musk time dilation"? By now they should have finished 1/3 scale Raptor tests, and be fabricating a full scale along with an test stand that can handle such. Hello? Where is it?

    Not like you to low value post...

    But, since you asked, I was wondering the same.

    We saw first raptor burn at IAC2016.
    Next we heard was at IAC 2017... 42 tests, 1,200s cumulative over the first year of testing.
    We've also heard testing continues this year.

    We may have to wait until IAC 2018 to get next quantitative status.

    Can I ask you a very simple question why do you think you’re entitled to know anything at this stage in the development of the BE-4?

    In my opinion Blue Origin don’t owe anyone outside of themselves, their relevant commercial partners and the USAF in the case of Vulcan anything information wise on the progression of the BE-4.

    I've never said or implied that I or anyone else is entitled* to this information. 
    What's your source of this snark?

    * Doesn't mean we aren't interested and ready to grab any bits that fall to the floor.

    The source of my so called snark is the seeming expectation for all commercial companies in this sector to act in the same PR led way that Space X does. Leading by PR often leads to things like hyperbole and unrealistic delivery dates for products. Maybe in this case less is more?

    However it's old school government contractors that say next to nothing about their developments (I'm thinking AJRD). Even though they are a publically traded company, and their shares are highly driven by public opinion, they don't seem to do much PR compared to SpaceX, BO, or RL. Or at least effective PR. Press release here and there about hot fires of RS-25, and may be one tiny snippet about AR-1 every year or so.

    You can't find any information online on some of their defunct programs from the past.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Star One on 03/02/2018 03:04 PM
    ...

    add:

    And to put the shoe on the other foot, we've heard twice now on BE-4 testing, but nothing more on Raptor. Aren't we overdue on a SX report on how Raptor is doing? Unless it's sliding into "Musk time dilation"? By now they should have finished 1/3 scale Raptor tests, and be fabricating a full scale along with an test stand that can handle such. Hello? Where is it?

    Not like you to low value post...

    But, since you asked, I was wondering the same.

    We saw first raptor burn at IAC2016.
    Next we heard was at IAC 2017... 42 tests, 1,200s cumulative over the first year of testing.
    We've also heard testing continues this year.

    We may have to wait until IAC 2018 to get next quantitative status.

    Can I ask you a very simple question why do you think you’re entitled to know anything at this stage in the development of the BE-4?

    In my opinion Blue Origin don’t owe anyone outside of themselves, their relevant commercial partners and the USAF in the case of Vulcan anything information wise on the progression of the BE-4.

    I've never said or implied that I or anyone else is entitled* to this information. 
    What's your source of this snark?

    * Doesn't mean we aren't interested and ready to grab any bits that fall to the floor.

    The source of my so called snark is the seeming expectation for all commercial companies in this sector to act in the same PR led way that Space X does. Leading by PR often leads to things like hyperbole and unrealistic delivery dates for products. Maybe in this case less is more?

    However it's old school government contractors that say next to nothing about their developments (I'm thinking AJRD). Even though they are a publically traded company, and their shares are highly driven by public opinion, they don't seem to do much PR compared to SpaceX, BO, or RL. Or at least effective PR. Press release here and there about hot fires of RS-25, and may be one tiny snippet about AR-1 every year or so.

    You can't find any information online on some of their defunct programs from the past.

    Wouldn’t that be more down to the federal government though considering how many of their products appear to be at the instigation of government customers?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: LouScheffer on 03/02/2018 03:12 PM

    We saw first raptor burn at IAC2016.
    Next we heard was at IAC 2017... 42 tests, 1,200s cumulative over the first year of testing.
    At least the SpaceX minimal update was more informative.

    42 tests (and assuming at most 4 test engines) implies at least one engine ran 10 times.

    1200 seconds total (and 42 tests) implies that at least one engine ran for at least 29 seconds.  That's enough time to reach steady state operation and thermal equilibrium for most components.

    The BE-4 update does not support even these minimal milestones of progress.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: gongora on 03/02/2018 03:59 PM

    We saw first raptor burn at IAC2016.
    Next we heard was at IAC 2017... 42 tests, 1,200s cumulative over the first year of testing.
    At least the SpaceX minimal update was more informative.

    42 tests (and assuming at most 4 test engines) implies at least one engine ran 10 times.

    1200 seconds total (and 42 tests) implies that at least one engine ran for at least 29 seconds.  That's enough time to reach steady state operation and thermal equilibrium for most components.

    The BE-4 update does not support even these minimal milestones of progress.

    Raptor's first firing was a year earlier than BE-4.  It's no surprise they're farther along in the testing.  Let's see where Blue is after a year of firing their engine.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: AncientU on 03/02/2018 05:56 PM
    Blue has had a full scale engine for a year (announced with pictures 3/6/17).  March 2107 announcements were that hot fire was imminent.
    Quote
    Here’s why the imminent test of Jeff Bezos’ BE-4 rocket engine is a huge deal
    https://arstechnica.com/science/2017/03/heres-why-the-imminent-test-of-jeff-bezos-be-4-rocket-engine-is-a-huge-deal/

    This is comparable to the first year of Raptor's existence (shown at IAC 2016 -- fired days before).
    So, even though Raptor testing began 6-7 months before BE-4, the comparison of year one for each engine is valid*.

    * I didn't bring the subject up, but was responding to someone who called out a comparison.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: gongora on 03/02/2018 06:04 PM
    Blue has had a full scale engine for a year (announced with pictures 3/6/17).  March 2107 announcements were that hot fire was imminent.
    Quote
    Here’s why the imminent test of Jeff Bezos’ BE-4 rocket engine is a huge deal
    https://arstechnica.com/science/2017/03/heres-why-the-imminent-test-of-jeff-bezos-be-4-rocket-engine-is-a-huge-deal/

    This is comparable to the first year of Raptor's existence (shown at IAC 2016 -- fired days before).
    So, even though Raptor testing began 6-7 months before BE-4, the comparison of year one for each engine is valid*.


    That is nonsense.  Raptor began test fires of a full engine an entire year before BE-4.

    Title: Re: Blue Origin's BE-4 Engine
    Post by: envy887 on 03/02/2018 06:18 PM
    Blue has had a full scale engine for a year (announced with pictures 3/6/17).  March 2107 announcements were that hot fire was imminent.
    Quote
    Here’s why the imminent test of Jeff Bezos’ BE-4 rocket engine is a huge deal
    https://arstechnica.com/science/2017/03/heres-why-the-imminent-test-of-jeff-bezos-be-4-rocket-engine-is-a-huge-deal/

    This is comparable to the first year of Raptor's existence (shown at IAC 2016 -- fired days before).
    So, even though Raptor testing began 6-7 months before BE-4, the comparison of year one for each engine is valid*.


    That is nonsense.  Raptor began test fires of a full engine an entire year before BE-4.

    Because it spent a lot more time between shipping out of the factory and first fire for some reason.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Rabidpanda on 03/02/2018 09:20 PM
    Blue has had a full scale engine for a year (announced with pictures 3/6/17).  March 2107 announcements were that hot fire was imminent.
    Quote
    Here’s why the imminent test of Jeff Bezos’ BE-4 rocket engine is a huge deal
    https://arstechnica.com/science/2017/03/heres-why-the-imminent-test-of-jeff-bezos-be-4-rocket-engine-is-a-huge-deal/

    This is comparable to the first year of Raptor's existence (shown at IAC 2016 -- fired days before).
    So, even though Raptor testing began 6-7 months before BE-4, the comparison of year one for each engine is valid*.


    That is nonsense.  Raptor began test fires of a full engine an entire year before BE-4.

    Because it spent a lot more time between shipping out of the factory and first fire for some reason.

    We don't know how long Raptor sat on the test stand before it was fired for the first time.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Zucal on 03/02/2018 10:51 PM
    We don't know how long Raptor sat on the test stand before it was fired for the first time.

    The first Raptor (subscale development engine) shipped to McGregor the night of August 08, 2016. It was first test fired on the night of September 25, 2016.

    48 days / 1 month & 17 days
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Nomadd on 03/03/2018 07:34 AM
      March 2107 announcements were that hot fire was imminent.

    I know they're slow, but not that slow.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Darkseraph on 03/03/2018 01:40 PM
    That would be the "Gradatim". The Ferociter is the enginenot being a subscale demonstrator, the hardware on the test stand is representative of the final product and multiple engines are in the pipeline. Also, BE-4 is significantly larger than Raptor in both size and thrust. Although one or more of these engines could blow up on the stand, Blue operates hardware rich and could be back testing again in months. I'd be honestly surprised if BE-4 is not qualified by 2019 Q2.

    Raptor is a far cooler name than BE-4 though!
    Title: Re: Blue Origin's BE-4 Engine
    Post by: AncientU on 03/03/2018 03:41 PM
    Raptor began test fires of a full engine an entire year before BE-4.
    I think that SpaceX has been test firing a sub-scale Raptor, probably not a flight-type engine, and we haven't seen that engine in months.

    BE-4 is undergoing full-scale testing of nearly-flight-type hardware, as I understand things.

     - Ed Kyle

    EM has specifically stated that this engine was not a flight engine -- that this is the FFSC test version and the flight engine would be 'light and tight.'  JB is maybe taking a different route in making their first orbital engine nearly-flight-type, but I think it's possible that this engine is also a full scale test engine to demonstrate control of the ORSC cycle -- the first in US history.  A flight engine on first iteration would show comparable 'ferociter' as flying to orbit a full scale New Glenn on first NG flight... and trying to land it on their ship.  Many here believe that this is the intent. (i don't)  All are incredibly bold actions, and justify going 'graditum' on their test steps leading up to launch.

    Anyone have a quote from Blue that this is a flight engine?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: TrevorMonty on 03/03/2018 05:27 PM
    Raptor and BE4 engines are not competiting against each other. The LVs that use them might compete for payloads.

    BE4 vs AR1 now that is a race for Vulcan.  Although BE4 can't really loss as will fly in NG regardless of outcome.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: AncientU on 03/03/2018 05:46 PM
    Raptor and BE4 engines are not competiting against each other. The LVs that use them might compete for payloads.

    BE4 vs AR1 now that is a race for Vulcan.  Although BE4 can't really loss as will fly in NG regardless of outcome.

    Correct.

    Both are attempts to power next generation rockets.  BE-4 will double down on reusable rockets as the future, and Raptor will power the world's first affordable, reusable exploration-class vehicle.

    As such, these development programs are each a huge contribution to the USA's future in spaceflight.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Navier–Stokes on 03/03/2018 07:00 PM
    Anyone have a quote from Blue that this is a flight engine?
    Brett Alexander (Director of Business Development and Strategy for Blue Origin) stated that the engine being tested is flight weight (see https://www.youtube.com/watch?v=lftY2-NKX0E?t=5h32m33s).
    Title: Re: Blue Origin's BE-4 Engine
    Post by: symbios on 03/12/2018 08:42 PM
    I think this should be in here to:
    Great news:
    Quote
    Bob Smith, Blue Origin: making good progress on BE-4 engine. Recently had 114-second firing at 65% power. #SatShow
    https://twitter.com/jeff_foust/status/973297209860153349
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 03/12/2018 08:59 PM
    We're now crossing into the territory of "usable for orbital launcher" performance (not close to "desirable for launcher" yet). Good.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: WindnWar on 03/12/2018 09:05 PM
    This seems like it has taken them a considerable amount of time to get to that point. Has there been any tests at full power yet?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: mme on 03/12/2018 10:43 PM
    This seems like it has taken them a considerable amount of time to get to that point. Has there been any tests at full power yet?
    I think as spectators we're just impatient. They are light years ahead of the competition and Blue is super serious about the Gradatim in "Gradatim Ferociter."
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Robotbeat on 03/13/2018 12:33 AM
    This seems like it has taken them a considerable amount of time to get to that point. Has there been any tests at full power yet?
    I think as spectators we're just impatient. They are light years ahead of the competition and Blue is super serious about the Gradatim in "Gradatim Ferociter."
    Really? They look to be a good 6 months behind Raptor. Did you mean AR-1? If so, I agree.

    (Not that I'm worried about Blue. As you say, Blue will take their time. But they're taking a very good technical approach and they have a VERY large and infinitely patient funding source.)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: mme on 03/13/2018 02:12 AM
    This seems like it has taken them a considerable amount of time to get to that point. Has there been any tests at full power yet?
    I think as spectators we're just impatient. They are light years ahead of the competition and Blue is super serious about the Gradatim in "Gradatim Ferociter."
    Really? They look to be a good 6 months behind Raptor. Did you mean AR-1? If so, I agree.

    (Not that I'm worried about Blue. As you say, Blue will take their time. But they're taking a very good technical approach and they have a VERY large and infinitely patient funding source.)
    Yeah, I meant AR1 which is supposedly in an actual competition with BE-4 and yet AFAICT they are still testing engine components. I wasn't being snarky when I said they take the Gradatim seriously. I just meant that they will won't rush or take any shortcuts to hurry.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Robotbeat on 03/13/2018 02:16 AM
    Yeah, they do seem committed to that. Part of me agrees with QuantumG, though, that this has a huge opportunity cost (i.e. it's incredibly wasteful). But hey, at least it's going in the right direction! And I suppose it's good that, if you have two, well-funded, cutting edge space companies heading in the right direction, that one of them plays it safe in case the one that's ahead runs into problems.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Darkseraph on 03/13/2018 09:02 AM
    BE-4 appears to be making steady progress since its first firing and well on the way to a full power/ full duration test. Expecting this engine to be qualified easily by the end of the year, hiccups included. The future looks dim for AR-1 unless it can be pitched to NASA for SLS Block 2 or Congress keeps it alive to completion anyway like J2X, arguing it's necessary for dubious national security reasons. 


    Cannot wait to see 7 of these fire at once in 2021. :)   
    Title: Re: Blue Origin's BE-4 Engine
    Post by: LouScheffer on 03/13/2018 11:36 AM
    I think this should be in here to:
    Great news:
    Quote
    Bob Smith, Blue Origin: making good progress on BE-4 engine. Recently had 114-second firing at 65% power. #SatShow
    https://twitter.com/jeff_foust/status/973297209860153349
    114 seconds is an interesting number.   It's much longer than it takes to get to steady state flows and operation, but less than a full duration firing.  I can't see any reason to plan a test of this length.  So it seems likely this was intended to be full duration,  but they ran into a red-line somewhere and the test was cut off.

    On the good side, there cannot be a lot of duration-limiting problems left, or they could not get to 122 seconds.   So full duration should follow pretty quickly.  Then they will have measured temperatures and stresses for all parts, and can start raising the power.  This should be a more-or-less straightforward extrapolation of previously tried conditions, and has seemed to go fairly smoothly for other engines (almost all of them get uprated at some point in their life, usually without too much drama).

    The main remaining risk (to me, as a naive outsider) would be the behavior of materials under the full flow, full stress, hot oxygen environment.   Since this is such an obvious concern, they have surely planned for this.  But surprises in this area have led to long qualification campaigns for the Soviet ORSC engines.

    Title: Re: Blue Origin's BE-4 Engine
    Post by: gongora on 03/13/2018 12:50 PM
    114 seconds is an interesting number.   It's much longer than it takes to get to steady state flows and operation, but less than a full duration firing.  I can't see any reason to plan a test of this length.  So it seems likely this was intended to be full duration,  but they ran into a red-line somewhere and the test was cut off.

    Raptor tests are limited by the size of the propellant tanks at the test stand.  Do we know how long of a burn the Blue test stand would support?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: woods170 on 03/13/2018 01:05 PM
    114 seconds is an interesting number.   It's much longer than it takes to get to steady state flows and operation, but less than a full duration firing.  I can't see any reason to plan a test of this length.  So it seems likely this was intended to be full duration,  but they ran into a red-line somewhere and the test was cut off.

    Raptor tests are limited by the size of the propellant tanks at the test stand.  Do we know how long of a burn the Blue test stand would support?

    No. There is virtually nothing publically known about Blue's BE-4 test stand.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: LouScheffer on 03/13/2018 01:23 PM
    114 seconds is an interesting number.   It's much longer than it takes to get to steady state flows and operation, but less than a full duration firing.  I can't see any reason to plan a test of this length.  So it seems likely this was intended to be full duration,  but they ran into a red-line somewhere and the test was cut off.
    Raptor tests are limited by the size of the propellant tanks at the test stand.  Do we know how long of a burn the Blue test stand would support?
    No. There is virtually nothing publically known about Blue's BE-4 test stand.
    While nothing is known about the stand, I'd be extremely surprised if ULA (and Blue themselves) dd not demand a series of full power, full duration burns.   So if this stand can't do this, they must be planning another test stand with bigger tanks.  But that seems like un-needed duplication, so I'd be very surprised if tank limits were the cause of the short duration.  Of course it's possible that bigger tanks are on order, or the tanks were not full, etc., but that seems unlikely to me.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: jebbo on 03/13/2018 01:39 PM
    Presumably it is this stand?

    link (https://www.google.co.uk/maps/place/West+Texas+Suborbital+Launch+Site/@31.4296702,-104.7198876,173m/data=!3m1!1e3!4m5!3m4!1s0x86e5cc0b9031e3c7:0xb0d4dcff3a06f329!8m2!3d31.422927!4d-104.757152)

    Though I'm not sure what can be gleaned from that ...
    Title: Re: Blue Origin's BE-4 Engine
    Post by: LouScheffer on 03/13/2018 01:59 PM
    Presumably it is this stand?

    link (https://www.google.co.uk/maps/place/West+Texas+Suborbital+Launch+Site/@31.4296702,-104.7198876,173m/data=!3m1!1e3!4m5!3m4!1s0x86e5cc0b9031e3c7:0xb0d4dcff3a06f329!8m2!3d31.422927!4d-104.757152)

    Though I'm not sure what can be gleaned from that ...

    Vulcan first stage is supposed to be something like 5.4m diameter and 32 meters long.  That's 732 m^3, or about 368 m^3 per engine.

    The test stand has 4 tanks that look like 3.66 m by 20 meters, and one slightly smaller (3.2 by 17m ?).  That's 210 m^3 each for the big tanks.  Even allowing for insulation, etc, it would appear the tanks are big enough to support a full duration burn.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: acsawdey on 03/13/2018 02:17 PM
    Presumably it is this stand?

    link (https://www.google.co.uk/maps/place/West+Texas+Suborbital+Launch+Site/@31.4296702,-104.7198876,173m/data=!3m1!1e3!4m5!3m4!1s0x86e5cc0b9031e3c7:0xb0d4dcff3a06f329!8m2!3d31.422927!4d-104.757152)

    Though I'm not sure what can be gleaned from that ...

    Vulcan first stage is supposed to be something like 5.4m diameter and 32 meters long.  That's 732 m^3, or about 368 m^3 per engine.

    The test stand has 4 tanks that look like 3.66 m by 20 meters, and one slightly smaller (3.2 by 17m ?).  That's 210 m^3 each for the big tanks.  Even allowing for insulation, etc, it would appear the tanks are big enough to support a full duration burn.

    Don't you want to look at just the two vertical tanks on the stand itself? It looks like they are suspended in cages so they can weigh the propellant to measure flow rate. Though perhaps all the tanks could be used if you just wanted to get max duration.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 03/13/2018 05:32 PM
    Suggest duration is set by potential ORSC wear/erosion/thermal stress of certain engine components.

    You'd prove a burn to a certain point, then afterward check those components to see that it remained to within tolerances.

    There's a lot of work that goes on between burns, in some cases days to weeks.

    Remember, the point isn't just to operate the engine, but to understand/prove its operation meets its design expectation/requirements/margin by working the way its supposed to. Once that happens, you can proceed further.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: FutureSpaceTourist on 03/13/2018 10:12 PM
    Quote
    New test video of Blue’s 550K lbf thrust, ox-rich staged combustion, LNG-fueled BE-4 engine. The test is a mixture ratio sweep at 65% power level and 114 seconds in duration. Methane (or LNG) has proved to be an outstanding fuel choice. @BlueOrigin #GradatimFerociter

    https://twitter.com/jeffbezos/status/973696994332983299

    Edit: video added
    Title: Re: Blue Origin's BE-4 Engine
    Post by: acsawdey on 03/13/2018 10:38 PM
    So if we have 65% of 2400 kN thrust and 311 Isp then we can calculate:

    Ve = 311*9.8 = 3048 m/s

    F = 0.65*2400 = 1560 kN

    F = mdot * Ve --> mdot = 1560000/3048 = 511.8 kg/s

    A 114 second firing should then use 58346 kg of propellants .. which is probably off because they were doing a mixture sweep.

    Anybody want to make a stab at how this relates to the size of the tanks seen in the google sat image posted a bit earlier?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: LastStarFighter on 03/13/2018 10:49 PM
    Presumably it is this stand?

    link (https://www.google.co.uk/maps/place/West+Texas+Suborbital+Launch+Site/@31.4296702,-104.7198876,173m/data=!3m1!1e3!4m5!3m4!1s0x86e5cc0b9031e3c7:0xb0d4dcff3a06f329!8m2!3d31.422927!4d-104.757152)

    Though I'm not sure what can be gleaned from that ...

    That is the New Shepard launch site. The BE-4 test stand is 3-4km ENE of that launch pad I believe.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: cletus on 03/14/2018 03:56 AM
    Quote
    New test video of Blue’s 550K lbf thrust, ox-rich staged combustion, LNG-fueled BE-4 engine. The test is a mixture ratio sweep at 65% power level and 114 seconds in duration. Methane (or LNG) has proved to be an outstanding fuel choice. @BlueOrigin #GradatimFerociter

    https://twitter.com/jeffbezos/status/973696994332983299

    Edit: video added

    Awesome!!

    Also, I understood most of that, but what does "mixture ratio sweep" mean?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Steven Pietrobon on 03/14/2018 04:14 AM
    Also, I understood most of that, but what does "mixture ratio sweep" mean?

    The mixture ratio is referring the oxidiser mass rate to fuel mass rate ratio. With methalox that varies from about 3.5 to 3.8. Some rocket engines have the ability to vary the mixture ratio. The sweep will vary the mixture ratio from the minimum value (most fuel rich) to the maximum value (most oxidiser rich) during the rocket burn.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: hkultala on 03/14/2018 04:25 AM
    Also, I understood most of that, but what does "mixture ratio sweep" mean?

    The mixture ratio is referring the oxidiser mass rate to fuel mass rate ratio. With methalox that varies from about 3.5 to 3.8. Some rocket engines have the ability to vary the mixture ratio. The sweep will vary the mixture ratio from the minimum value (most fuel rich) to the maximum value (most oxidiser rich) during the rocket burn.

    So, 3.5 for maximum isp and 3.8 for maximum impulse density and thrust?

    What is the reason the maximum is about 3.8, not 4 to get all the methane burned? Would be too corrosive for the chamber and nozzle, or something else?



    Title: Re: Blue Origin's BE-4 Engine
    Post by: Steven Pietrobon on 03/14/2018 04:59 AM
    So, 3.5 for maximum isp and 3.8 for maximum impulse density and thrust?

    Yes, that's one purpose. The other is getting both tanks to empty at the same time, due to small variations in the flow rates during the main burn and the initial masses of the propellants.

    Quote
    What is the reason the maximum is about 3.8, not 4 to get all the methane burned? Would be too corrosive for the chamber and nozzle, or something else?

    You want the ratio to be always fuel rich, otherwise your hot oxidiser rich gases in the combustion chamber will want to burn with the metals in the chamber. In the parlance of rocket scientists, you want avoid an "engine rich" situation! :-) A value of 4 is too close to (and greater than) the stoichiometric ratio of 3.9891.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: jebbo on 03/14/2018 06:19 AM
    That is the New Shepard launch site. The BE-4 test stand is 3-4km ENE of that launch pad I believe.

    I don't think it is: a) this is the bigger of the two stands and b) there is nothing ENE of this, but there is a smaller test stand ~SW of this ... smaller stand is near the bottom left and larger stand near the top right of this
    link (https://www.google.co.uk/maps/place/West+Texas+Suborbital+Launch+Site/@31.4123963,-104.7369039,5290m/data=!3m1!1e3!4m5!3m4!1s0x86e5cc0b9031e3c7:0xb0d4dcff3a06f329!8m2!3d31.422927!4d-104.757152).

    Edit: the other test stand is here (https://www.google.co.uk/maps/place/West+Texas+Suborbital+Launch+Site/@31.3945959,-104.7558538,120m/data=!3m1!1e3!4m5!3m4!1s0x86e5cc0b9031e3c7:0xb0d4dcff3a06f329!8m2!3d31.422927!4d-104.757152).

    --- Tony
    Title: Re: Blue Origin's BE-4 Engine
    Post by: woods170 on 03/14/2018 08:54 AM
    Presumably it is this stand?

    link (https://www.google.co.uk/maps/place/West+Texas+Suborbital+Launch+Site/@31.4296702,-104.7198876,173m/data=!3m1!1e3!4m5!3m4!1s0x86e5cc0b9031e3c7:0xb0d4dcff3a06f329!8m2!3d31.422927!4d-104.757152)

    Though I'm not sure what can be gleaned from that ...

    Vulcan first stage is supposed to be something like 5.4m diameter and 32 meters long.  That's 732 m^3, or about 368 m^3 per engine.

    The test stand has 4 tanks that look like 3.66 m by 20 meters, and one slightly smaller (3.2 by 17m ?).  That's 210 m^3 each for the big tanks.  Even allowing for insulation, etc, it would appear the tanks are big enough to support a full duration burn.

    Don't you want to look at just the two vertical tanks on the stand itself? It looks like they are suspended in cages so they can weigh the propellant to measure flow rate. Though perhaps all the tanks could be used if you just wanted to get max duration.

    The conversation above is exactly why I mentioned that there is virtually nothing known about Blue's BE-4 test stand.
    There is only so much one can infer from a low-res Google maps image.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Navier–Stokes on 03/14/2018 03:08 PM
    Quote
    New test video of Blue’s 550K lbf thrust, ox-rich staged combustion, LNG-fueled BE-4 engine. The test is a mixture ratio sweep at 65% power level and 114 seconds in duration. Methane (or LNG) has proved to be an outstanding fuel choice. @BlueOrigin #GradatimFerociter

    https://twitter.com/jeffbezos/status/973696994332983299

    Edit: video added

    YouTube mirror:
    https://www.youtube.com/watch?v=Fp0WgodhR7s
    Title: Re: Blue Origin's BE-4 Engine
    Post by: acsawdey on 03/14/2018 03:33 PM
    So if we have 65% of 2400 kN thrust and 311 Isp then we can calculate:

    Ve = 311*9.8 = 3048 m/s

    F = 0.65*2400 = 1560 kN

    F = mdot * Ve --> mdot = 1560000/3048 = 511.8 kg/s

    A 114 second firing should then use 58346 kg of propellants .. which is probably off because they were doing a mixture sweep.

    Anybody want to make a stab at how this relates to the size of the tanks seen in the google sat image posted a bit earlier?

    Ok, assuming a 3.8:1 OF ratio we get 12155 kg of LNG and 46189 kg of lox.
    Using 1141 kg/m3 for lox and 450 kg/m3 for LNG, the propellant volumes are 40.5 m3 of lox and 27 m3 of LNG.

    Vulcan first stage is supposed to be something like 5.4m diameter and 32 meters long.  That's 732 m^3, or about 368 m^3 per engine.

    The test stand has 4 tanks that look like 3.66 m by 20 meters, and one slightly smaller (3.2 by 17m ?).  That's 210 m^3 each for the big tanks.  Even allowing for insulation, etc, it would appear the tanks are big enough to support a full duration burn.

    Scaling up from 65% to 100% and increasing from 114 seconds to 240 seconds they still only need 131 m3 of lox and 87 of LNG.

    I'm not sure about that 368 m^3 tank volume per engine. I think the densities get us something like 1.5:1 OF by volume which means 368 m^3 of propellant would weigh 318000 kg and a 2400kN engine can't lift it off the pad.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Darkseraph on 03/14/2018 03:44 PM
    Awesome video. The BE4 exhaust appears very different to the Raptor exhaust! At 65%, BE-4 is very close to Raptor at full power!

    (https://cdn.geekwire.com/wp-content/uploads/2018/03/180313-blueorigin-630x354.jpg) 
    (http://cdn.geekwire.com/wp-content/uploads/2016/09/160926-spacex-raptor.jpg)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Davidthefat on 03/14/2018 05:14 PM
    Keep in mind the substantially different chamber pressures, and the fact that one does not have a seal.

    I'm 100% sure Raptor has seals. May not be hot gas purge seals, but still seals nonetheless.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Chasm on 03/15/2018 05:27 PM
    Presumably it is this stand?

    link (https://www.google.co.uk/maps/place/West+Texas+Suborbital+Launch+Site/@31.4296702,-104.7198876,173m/data=!3m1!1e3!4m5!3m4!1s0x86e5cc0b9031e3c7:0xb0d4dcff3a06f329!8m2!3d31.422927!4d-104.757152)

    Though I'm not sure what can be gleaned from that ...

    That is their new big stand, the old small one to the southwest of it close to the road.

    Launch site is to the west of the big stand.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: FutureSpaceTourist on 04/16/2018 03:46 PM
    Quote
    Replying to @timmermansr @SierraNevCorp @blueorigin

    Although in lesser scale than in 2017, @blueorigin is also visibly present this year

    https://twitter.com/Tschnn/status/985666496650100736
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 04/16/2018 10:48 PM
    SNC and Jeff Bezos’ Blue Origin show off hardware at Colorado’s Space Symposium (https://www.geekwire.com/2018/snc-jeff-bezos-blue-origin-show-off-hardware-colorados-space-symposium/)

    (https://cdn.geekwire.com/wp-content/uploads/2018/04/180416-blue2-630x840.jpg)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: HMXHMX on 04/17/2018 03:53 AM
    A few more high resolution photos.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: woods170 on 04/17/2018 07:08 AM
    Me love rocket engine hardware.

    Now, Aerojet, show us yours.  ;)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Semmel on 04/17/2018 08:59 AM
    What beautiful images, thank you very much!

    add: Nice to see how the LNG splits after its pump and partly goes into the Nozzle for regenerative cooling. Also the LOX after its pump loops around and goes into the pre-burner. I cant seem to find the pipe that the LNG takes to the pre-burner, but maybe its hidden in all the spaghetti. Nice to see how the pre-burner directly connects to the turbine and is connected to the combustion chamber. On the other side of the turbine are first the LOX pump and then the LNG pump. But I dont see any gearbox between the LOX pump and the LNG pump. I thought there should be one but maybe they are running with the same RPM and mixture ratio is controlled by the inlet valves?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Nomic on 04/17/2018 10:35 AM
    Great photos. I'd guess the LNG line to the preburner is the one below. Also note the LOX low pressure pump, Blue newsletter last year talked about it being 3D printed in aluminium.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Semmel on 04/17/2018 12:35 PM
    Ohh right, I totally didnt look for it there as I expected it to come after the heat exchange with the engine. But makes sense that this is the LNG fuel line.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: FutureSpaceTourist on 04/17/2018 01:41 PM
    Jeff Foust has posted some too, including this display info which is interesting

    https://twitter.com/jeff_foust/status/986236025688264704
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 04/17/2018 03:52 PM
    Didn't they have one that blew up before that in summer? Lost 3 months repairing the test stand?

    So isn't this the first successfully hotfired one? Its little details like this that annoy with BO (and Bezos in general). "It never happened ..."

    BTW great pics HMX, couldn't come this year, you know exactly where to frame what we need to see here.

    Looks like some of the preburner assembly and manifold have been redesigned since I last saw the side mounted TP version from the top mount.

    add:
    Perfectly illustrates why I dislike BO's/Bezos communications:

    https://mobile.twitter.com/blueorigin/status/863881495169048576

    They blew up a powerpack, not a full engine.

    They tested the powerpack ahead of engine arrival many times at rated flow. They got the engine on the test stand for first firing. The powerpack failed while bringing up the engine. They blamed the powerpack. The test stand was damaged. If the test stand is damaged, so is the engine.

    Exactly the two-bit shit I despise that this enables. And it's in no way "being excellent to each other" here. And evasion of the truth as far as we can attempt to prove it with the tidbits released, which are sometimes editted/deleted. To make somebody look better than they are. Earns my ire. Not worth a post.

    Its a nice designed engine though.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Rabidpanda on 04/17/2018 04:00 PM
    Didn't they have one that blew up before that in summer? Lost 3 months repairing the test stand?

    So isn't this the first successfully hotfired one? Its little details like this that annoy with BO (and Bezos in general). "It never happened ..."

    BTW great pics HMX, couldn't come this year, you know exactly where to frame what we need to see here.

    Looks like some of the preburner assembly and manifold have been redesigned since I last saw the side mounted TP version from the top mount.

    https://mobile.twitter.com/blueorigin/status/863881495169048576

    They blew up a powerpack, not a full engine.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: woods170 on 04/17/2018 06:05 PM
    Didn't they have one that blew up before that in summer? Lost 3 months repairing the test stand?

    So isn't this the first successfully hotfired one? Its little details like this that annoy with BO (and Bezos in general). "It never happened ..."

    BTW great pics HMX, couldn't come this year, you know exactly where to frame what we need to see here.

    Looks like some of the preburner assembly and manifold have been redesigned since I last saw the side mounted TP version from the top mount.

    add:
    Perfectly illustrates why I dislike BO's/Bezos communications:

    https://mobile.twitter.com/blueorigin/status/863881495169048576

    They blew up a powerpack, not a full engine.

    They tested the powerpack ahead of engine arrival many times at rated flow. They got the engine on the test stand for first firing. The powerpack failed while bringing up the engine. They blamed the powerpack. The test stand was damaged. If the test stand is damaged, so is the engine.

    Exactly the two-bit shit I despise that this enables. And it's in no way "being excellent to each other" here. And evasion of the truth as far as we can attempt to prove it with the tidbits released, which are sometimes editted/deleted. To make somebody look better than they are. Earns my ire. Not worth a post.

    Its a nice designed engine though.

    Dislike all you want.

    Welcome to the real world. Where proprietary rules.

    The truth is only revealed on a "need to know"-only basis.

    And you don't need to know.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Rabidpanda on 04/17/2018 06:30 PM

    They tested the powerpack ahead of engine arrival many times at rated flow. They got the engine on the test stand for first firing. The powerpack failed while bringing up the engine. They blamed the powerpack. The test stand was damaged. If the test stand is damaged, so is the engine.

    Exactly the two-bit shit I despise that this enables. And it's in no way "being excellent to each other" here. And evasion of the truth as far as we can attempt to prove it with the tidbits released, which are sometimes editted/deleted. To make somebody look better than they are. Earns my ire. Not worth a post.

    Its a nice designed engine though.

    You are inferring a lot without any evidence. What makes you think that the powerpack was attached to the engine when it failed? Why would they publicly announce that they had a powerpack failure, but then lie about whether or not the engine was involved?

    Isn't the simpler answer that the powerpack failed during powerpack testing (without the engine), which then delayed the first engine hot fire until October?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 04/17/2018 08:45 PM

    They tested the powerpack ahead of engine arrival many times at rated flow. They got the engine on the test stand for first firing. The powerpack failed while bringing up the engine. They blamed the powerpack. The test stand was damaged. If the test stand is damaged, so is the engine.

    Exactly the two-bit shit I despise that this enables. And it's in no way "being excellent to each other" here. And evasion of the truth as far as we can attempt to prove it with the tidbits released, which are sometimes editted/deleted. To make somebody look better than they are. Earns my ire. Not worth a post.

    Its a nice designed engine though.

    You are inferring a lot without any evidence.
    False.

    They made multiple announcements about the powerpack ahead of arrival of engines on site.

    They indicated that the engine was to be given first hotfire then.

    Quote
    What makes you think that the powerpack was attached to the engine when it failed?

    That they said so prior?

    Quote
    Why would they publicly announce that they had a powerpack failure, but then lie about whether or not the engine was involved?
    Because a powerpack can be a failure of an engine as well as being a seperate test.

    (Can and does occur in flight as well.)

    Quote
    Isn't the simpler answer that the powerpack failed during powerpack testing (without the engine), which then delayed the first engine hot fire until October?
    They chose to omit details, as well as didn't illustrate the extent of a multi month repair.

    And, as we all know, when you test an engine the first time, the difference in powerpack alone against that of injectior/compustion chamber means a pressure buildup, of the kind that can do significant damage when it lets go.

    So all the parts fit together neatly. While they don't the other way round. Duh.

    Its just skillful "disinformation". Because yes you can say that a manifold or the preburner on the powerhead failed, and call it a powerhead failure.

    So they are not credible with a half truth you're defending.

    (And if I was ULA watching half truths, I'd likely wait off a year or two waiting for a real truth to.)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Space Ghost 1962 on 04/17/2018 08:49 PM
    And you don't need to know.

    And they don't need to "look good" either. Another two bit move that makes them look like a "fly by night" group. Hurrah.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Rabidpanda on 04/17/2018 10:26 PM

    You are inferring a lot without any evidence.
    False.

    They made multiple announcements about the powerpack ahead of arrival of engines on site.

    They indicated that the engine was to be given first hotfire then.

    Quote
    What makes you think that the powerpack was attached to the engine when it failed?

    That they said so prior?


    No, they didn't.

    We know the first engine was assembled in March but there is no evidence that an engine hot fire was attempted in May.

    https://twitter.com/blueorigin/status/863881495169048576?s=21

    https://twitter.com/blueorigin/status/863881837000638464?s=21

    And then in October:

    https://twitter.com/blueorigin/status/921095318669873154?s=21

    There are two possible explanations:

    1) The powerpack failure that occurred in early May was not related to a full engine hot fire attempt, but rather was a continuation of powerpack-only testing that they had already been doing. This is consistent with all the public information that Blue has released. Perhaps they were waiting to hot fire the full engine until they had finished this powerpack testing.

    2) Blue origin blew up a full engine in May and is intentionally deceiving everyone by calling the hot fire in October the 'first time', both when it occurred and now at the Space Symposium.

    If they were happy to announce publicly that they had a powerpack failure (they didn't need to) why would they then try to lie about the status of the first full engine hot fire? It doesn't make any sense. There is no incentive for them to lie and no evidence that they are.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: woods170 on 04/18/2018 06:50 AM
    And you don't need to know.

    And they don't need to "look good" either. Another two bit move that makes them look like a "fly by night" group. Hurrah.

    That's what independent money does. No real need to "look good" and no real need to be transparent and open.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Redmat on 04/18/2018 08:33 AM
    Hey !

    Is it possible to calculate New Glenn's delta-v with BE-4 knowledges we acquired ?
    I mean, did we have enought informations (like mass wet/mass dry of each stage, etc...) ?

    Unfortunately, i'm not competent to calculate it. I know the existence of delta-v thanks to kerbal space program game (and mechjeb addons).

    But i would like to compare it with others results (like those i've in KSP ) ;D
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Nomic on 04/18/2018 11:06 AM
    Stage combustion engines are so integrated don't quite understand how testing the powerpack as a whole on its own (not components) works. Still need something to control the back pressure if its not going through the MCC injector, also without the nozzle less pressure drop on the fuel side. The IPD seemed to include everything down to a short nozzle. So don't really see a huge difference between losing a powerpack and losing an engine.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Aurora on 04/18/2018 05:28 PM
    Blue Origin CEO Bob Smith  BE4 will be able to launch 100 missions


    https://www.cnbc.com/2018/04/18/blue-origin-ceo-bob-smith-be-4-will-be-able-to-launch-100-missions.html

    Title: Re: Blue Origin's BE-4 Engine
    Post by: meberbs on 04/18/2018 09:25 PM
    Stage combustion engines are so integrated don't quite understand how testing the powerpack as a whole on its own (not components) works. Still need something to control the back pressure if its not going through the MCC injector, also without the nozzle less pressure drop on the fuel side. The IPD seemed to include everything down to a short nozzle. So don't really see a huge difference between losing a powerpack and losing an engine.
    Here is a post discussing J2X powerpack testing. A powerpack is not a full engine.

    https://blogs.nasa.gov/J2X/2012/02/21/post_1329851305074/
    Title: Re: Blue Origin's BE-4 Engine
    Post by: HMXHMX on 04/19/2018 03:32 AM
    Stage combustion engines are so integrated don't quite understand how testing the powerpack as a whole on its own (not components) works. Still need something to control the back pressure if its not going through the MCC injector, also without the nozzle less pressure drop on the fuel side. The IPD seemed to include everything down to a short nozzle. So don't really see a huge difference between losing a powerpack and losing an engine.
    Here is a post discussing J2X powerpack testing. A powerpack is not a full engine.

    https://blogs.nasa.gov/J2X/2012/02/21/post_1329851305074/

    In the case of an engine like the BE-4, the "powerpack" really is almost the whole engine, as it includes the preburner, TPA and likely also the main chamber injector (to get the appropriate pressure drop). All of the main chamber m-dot of LOX is flowing through the TPA and the preburner. Generally all that is lacking would be the main chamber and nozzle.  The J-2X is a gas generator cycle which is really not comparable to BE-4 since only about 2% of the overall engine m-dot is being consumed.

    Edit: typo
    Title: Re: Blue Origin's BE-4 Engine
    Post by: AncientU on 04/19/2018 01:50 PM
    Blue Origin CEO Bob Smith  BE4 will be able to launch 100 missions


    https://www.cnbc.com/2018/04/18/blue-origin-ceo-bob-smith-be-4-will-be-able-to-launch-100-missions.html

    Is 100 'full starts' equivalent to 100 missions then?  That would allow no pre-launch testing (stand testing before integration and/or static firing) or restarts during descent, confirming our supposition that the EDL could be totally passive aero-breaking.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: rst on 04/19/2018 02:36 PM
    Is 100 'full starts' equivalent to 100 missions then?  That would allow no pre-launch testing (stand testing before integration and/or static firing) or restarts during descent, confirming our supposition that the EDL could be totally passive aero-breaking.

    Or that they're willing to just accept a shorter life for landing engines. Even on Falcon 9, most of the booster engines start only once per flight (not counting pre-launch tests). And they may well be planning to avoid an entry burn, but skipping the landing burn would be ... ambitious. (Besides, if that's the plan, then what was that patent application for multi-engine coordinated landing burns all about?)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Johnnyhinbos on 04/19/2018 02:40 PM
    Stage combustion engines are so integrated don't quite understand how testing the powerpack as a whole on its own (not components) works. Still need something to control the back pressure if its not going through the MCC injector, also without the nozzle less pressure drop on the fuel side. The IPD seemed to include everything down to a short nozzle. So don't really see a huge difference between losing a powerpack and losing an engine.
    Here is a post discussing J2X powerpack testing. A powerpack is not a full engine.

    https://blogs.nasa.gov/J2X/2012/02/21/post_1329851305074/ (https://blogs.nasa.gov/J2X/2012/02/21/post_1329851305074/)

    In the case of an engine like the BE-4, the "powerpack" really is almost the whole engine, as it includes the preburner, TPA and likely also the main chamber injector (to get the appropriate pressure drop). All of the main chamber m-dot of LOX is flowing through the TPA and the preburner. Generally all that is lacking would be the main chamber and nozzle.  The J-2X is a gas generator cycle which is really not comparable to BE-4 since only about 2% of the overall engine m-dot is being consumed.

    Edit: typo
    Would you be willing to take a few of the great images you posted of the BE-4 and annotate with as much detail as you can? Is someone willing to start an "Anatomy of the BE-4 Engine" thread where such marked up images / diagrams live? Would love to see that, along with equivalent threads for Merlin 1D and Raptor and... So not a discussion thread but rather a visual description thread.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: HMXHMX on 04/19/2018 03:16 PM
    Stage combustion engines are so integrated don't quite understand how testing the powerpack as a whole on its own (not components) works. Still need something to control the back pressure if its not going through the MCC injector, also without the nozzle less pressure drop on the fuel side. The IPD seemed to include everything down to a short nozzle. So don't really see a huge difference between losing a powerpack and losing an engine.
    Here is a post discussing J2X powerpack testing. A powerpack is not a full engine.

    https://blogs.nasa.gov/J2X/2012/02/21/post_1329851305074/ (https://blogs.nasa.gov/J2X/2012/02/21/post_1329851305074/)

    In the case of an engine like the BE-4, the "powerpack" really is almost the whole engine, as it includes the preburner, TPA and likely also the main chamber injector (to get the appropriate pressure drop). All of the main chamber m-dot of LOX is flowing through the TPA and the preburner. Generally all that is lacking would be the main chamber and nozzle.  The J-2X is a gas generator cycle which is really not comparable to BE-4 since only about 2% of the overall engine m-dot is being consumed.

    Edit: typo
    Would you be willing to take a few of the great images you posted of the BE-4 and annotate with as much detail as you can? Is someone willing to start an "Anatomy of the BE-4 Engine" thread where such marked up images / diagrams live? Would love to see that, along with equivalent threads for Merlin 1D and Raptor and... So not a discussion thread but rather a visual description thread.

    It's a question of time.  Crazy busy running two nonprofits, and three companies.

    Hopefully someone else who is knowledgeable (and there are plenty on this forum) can step in and do it.  If nothing shows up by the weekend, I'll revisit.

    (I do believe someone has already done this for Raptor and 1D, by the way...)
    Title: Re: Blue Origin's BE-4 Engine
    Post by: AncientU on 04/20/2018 12:06 AM
    New article:
    Quote
    Blue Origin expects BE-4 qualification tests to be done by year’s end
    Quote
    “We continue to roll through our test program and hope to qualify that engine by the end of the year,” he said. “We’re walking our way through that just to make sure we understand and characterize the engine fully.”
    http://spacenews.com/blue-origin-expects-be-4-qualification-tests-to-be-done-by-years-end/
    Title: Re: Blue Origin's BE-4 Engine
    Post by: HMXHMX on 04/20/2018 04:45 AM
    Stage combustion engines are so integrated don't quite understand how testing the powerpack as a whole on its own (not components) works. Still need something to control the back pressure if its not going through the MCC injector, also without the nozzle less pressure drop on the fuel side. The IPD seemed to include everything down to a short nozzle. So don't really see a huge difference between losing a powerpack and losing an engine.
    Here is a post discussing J2X powerpack testing. A powerpack is not a full engine.

    https://blogs.nasa.gov/J2X/2012/02/21/post_1329851305074/ (https://blogs.nasa.gov/J2X/2012/02/21/post_1329851305074/)

    In the case of an engine like the BE-4, the "powerpack" really is almost the whole engine, as it includes the preburner, TPA and likely also the main chamber injector (to get the appropriate pressure drop). All of the main chamber m-dot of LOX is flowing through the TPA and the preburner. Generally all that is lacking would be the main chamber and nozzle.  The J-2X is a gas generator cycle which is really not comparable to BE-4 since only about 2% of the overall engine m-dot is being consumed.

    Edit: typo
    Would you be willing to take a few of the great images you posted of the BE-4 and annotate with as much detail as you can? Is someone willing to start an "Anatomy of the BE-4 Engine" thread where such marked up images / diagrams live? Would love to see that, along with equivalent threads for Merlin 1D and Raptor and... So not a discussion thread but rather a visual description thread.

    It's a question of time.  Crazy busy running two nonprofits, and three companies.

    Hopefully someone else who is knowledgeable (and there are plenty on this forum) can step in and do it.  If nothing shows up by the weekend, I'll revisit.

    (I do believe someone has already done this for Raptor and 1D, by the way...)

    So I did have a few minutes to cobble together some captions.  In my haste I may have missed or mislabeled something, so corrections welcome.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Steven Pietrobon on 04/20/2018 05:45 AM
    So I did have a few minutes to cobble together some captions.  In my haste I may have missed or mislabeled something, so corrections welcome.

    Great job! Minor nit. The arrow for the LOX High Pressure Discharge in Slide 2 is out of place. I've lightened up the image so that you can see the details better.

    So where is the LNG boost pump? Is it not needed?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: FutureSpaceTourist on 04/20/2018 05:47 AM
    Quote
    Blue Origin CEO says next-gen BE-4 rocket engine meets technical requirements

    BY ALAN BOYLE on April 19, 2018 at 3:30 pm

    COLORADO SPRINGS, Colo. — For years, there’s been a big question surrounding the next-generation BE-4 rocket engine that’s being built by Amazon billionaire Jeff Bezos’ Blue Origin space venture: Will it be good enough for United Launch Alliance, a crucial prospective customer?

    Now Blue Origin CEO Bob Smith says the BE-4 has passed all of the technical tests required for ULA to sign onto a production contract.

    https://www.geekwire.com/2018/blue-origin-ceo-says-next-gen-4-rocket-engine-meets-technical-requirements/
    Title: Re: Blue Origin's BE-4 Engine
    Post by: LouScheffer on 04/20/2018 10:13 AM
    A few questions about the engine:

    There seem to be at least 4 different materials, or at least surface finishes - dark grey (lox boost pump), medium grey (fuel valve), light grey (fuel manifold), and shiny.  A special material for the pre-burner, turbine, and pre-burner exhaust makes sense, since these need to resist hot oxygen gas.  Are the others all different materials, or just different finishes?  If different materials, why?

    Nothing in the structure looks flexible.  I'd assume this means some sort of flexible line before the intake ports that we see, and the entire engine moves as a unit when gimballed.  Is this correct?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: woods170 on 04/20/2018 10:51 AM
    A few questions about the engine:

    There seem to be at least 4 different materials, or at least surface finishes - dark grey (lox boost pump), medium grey (fuel valve), light grey (fuel manifold), and shiny.  A special material for the pre-burner, turbine, and pre-burner exhaust makes sense, since these need to resist hot oxygen gas.  Are the others all different materials, or just different finishes?  If different materials, why?

    Nothing in the structure looks flexible.  I'd assume this means some sort of flexible line before the intake ports that we see, and the entire engine moves as a unit when gimballed.  Is this correct?

    Yes. That's how it is mostly done with gimballing rocket engines.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: HMXHMX on 04/20/2018 11:34 AM
    So I did have a few minutes to cobble together some captions.  In my haste I may have missed or mislabeled something, so corrections welcome.

    Great job! Minor nit. The arrow for the LOX High Pressure Discharge in Slide 2 is out of place. I've lightened up the image so that you can see the details better.

    So where is the LNG boost pump? Is it not needed?

    Ah, thanks, fixed.

    As for the LNG boost pump, like you I noted it wasn't there but don't know why.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: LouScheffer on 04/20/2018 01:30 PM
    A few questions about the engine:

    There seem to be at least 4 different materials, or at least surface finishes - dark grey (lox boost pump), medium grey (fuel valve), light grey (fuel manifold), and shiny.  A special material for the pre-burner, turbine, and pre-burner exhaust makes sense, since these need to resist hot oxygen gas.  Are the others all different materials, or just different finishes?  If different materials, why?

    Nothing in the structure looks flexible.  I'd assume this means some sort of flexible line before the intake ports that we see, and the entire engine moves as a unit when gimballed.  Is this correct?

    Yes. That's how it is mostly done with gimballing rocket engines.
    At least some Russian engines work differently, I think.  Since they have one turbopump and several nozzles, and they want the nozzles to gimbal independently (for roll control, for example) the pump are fixed to the frame and the nozzles move.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: envy887 on 04/20/2018 02:48 PM
    Quote
    Blue Origin CEO says next-gen BE-4 rocket engine meets technical requirements

    BY ALAN BOYLE on April 19, 2018 at 3:30 pm

    COLORADO SPRINGS, Colo. — For years, there’s been a big question surrounding the next-generation BE-4 rocket engine that’s being built by Amazon billionaire Jeff Bezos’ Blue Origin space venture: Will it be good enough for United Launch Alliance, a crucial prospective customer?

    Now Blue Origin CEO Bob Smith says the BE-4 has passed all of the technical tests required for ULA to sign onto a production contract.

    https://www.geekwire.com/2018/blue-origin-ceo-says-next-gen-4-rocket-engine-meets-technical-requirements/

    So, they did a full-duration, full-pressure burn and got the required stability, thrust, and I_sp?

    I would think those are the minimum technical requirements.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Davidthefat on 04/20/2018 07:13 PM
    So I did have a few minutes to cobble together some captions.  In my haste I may have missed or mislabeled something, so corrections welcome.

    Great job! Minor nit. The arrow for the LOX High Pressure Discharge in Slide 2 is out of place. I've lightened up the image so that you can see the details better.

    So where is the LNG boost pump? Is it not needed?

    Ah, thanks, fixed.

    As for the LNG boost pump, like you I noted it wasn't there but don't know why.

    What if what you pointed out at the PB injector isn't actually it, but is buried downstream that within the gray cast structure? That preburner is inline with the main TP shaft and the pressures at the main discharge doesn't make sense...

    What if that jacket of cold LOX helps with something...

    Hmm...

    I'm thinking a kick pump is integrated into the inlet to the preburner assembly where you point to as the injector. The bolt patterns seem to indicate that there is a part bolted internally.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: HMXHMX on 04/20/2018 10:10 PM
    So I did have a few minutes to cobble together some captions.  In my haste I may have missed or mislabeled something, so corrections welcome.

    Great job! Minor nit. The arrow for the LOX High Pressure Discharge in Slide 2 is out of place. I've lightened up the image so that you can see the details better.

    So where is the LNG boost pump? Is it not needed?

    Ah, thanks, fixed.

    As for the LNG boost pump, like you I noted it wasn't there but don't know why.

    What if what you pointed out at the PB injector isn't actually it, but is buried downstream that within the gray cast structure? That preburner is inline with the main TP shaft and the pressures at the main discharge doesn't make sense...

    What if that jacket of cold LOX helps with something...

    Hmm...

    I'm thinking a kick pump is integrated into the inlet to the preburner assembly where you point to as the injector. The bolt patterns seem to indicate that there is a part bolted internally.

    There is already a LOX boost pump labeled, so I don't see any need for one at the inlet of the PB.  The PB will have an injector, a short combustion chamber (operating at perhaps 700°F±100) and a turbine to drive the single-shaft main propellant pumps.  The apparent PB length is just sufficient to provide space for those items.  Sometimes this cycle of engine will have a fuel kick pump (as is the case for the NK-33) but I don't see one in the BE-4 layout.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Davidthefat on 04/20/2018 10:48 PM
    So I did have a few minutes to cobble together some captions.  In my haste I may have missed or mislabeled something, so corrections welcome.

    Great job! Minor nit. The arrow for the LOX High Pressure Discharge in Slide 2 is out of place. I've lightened up the image so that you can see the details better.

    So where is the LNG boost pump? Is it not needed?

    Ah, thanks, fixed.

    As for the LNG boost pump, like you I noted it wasn't there but don't know why.

    What if what you pointed out at the PB injector isn't actually it, but is buried downstream that within the gray cast structure? That preburner is inline with the main TP shaft and the pressures at the main discharge doesn't make sense...

    What if that jacket of cold LOX helps with something...

    Hmm...

    I'm thinking a kick pump is integrated into the inlet to the preburner assembly where you point to as the injector. The bolt patterns seem to indicate that there is a part bolted internally.

    There is already a LOX boost pump labeled, so I don't see any need for one at the inlet of the PB.  The PB will have an injector, a short combustion chamber (operating at perhaps 700°F±100) and a turbine to drive the single-shaft main propellant pumps.  The apparent PB length is just sufficient to provide space for those items.  Sometimes this cycle of engine will have a fuel kick pump (as is the case for the NK-33) but I don't see one in the BE-4 layout.

    I was insinuating that the LOX may be used to keep the methane at a lower temp to help prevent cavitation at the kick pump. Might just be a coincidence in packaging I just threw that idea out there, but it will definitely help keep the walls of the combustor side of the preburner cooler.

    You'll need a much higher fuel pressure at the PB than at the main chamber as stuff flows from high to low pressures. You need a good pressure difference between the above the turbine (which is kick pump pressure minus the delta p in the PB injector) to below (which is effectively manifold pressure to the main injector) The kick pump I was referring to being embedded in the PB assembly is the fuel kick pump. The fuel going to the regen chambers is main chamber pressure + main injector delta P + delta P in the cooling channels and pipes.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Kabloona on 04/21/2018 03:26 AM
    Quote
    Blue Origin CEO says next-gen BE-4 rocket engine meets technical requirements

    BY ALAN BOYLE on April 19, 2018 at 3:30 pm

    COLORADO SPRINGS, Colo. — For years, there’s been a big question surrounding the next-generation BE-4 rocket engine that’s being built by Amazon billionaire Jeff Bezos’ Blue Origin space venture: Will it be good enough for United Launch Alliance, a crucial prospective customer?

    Now Blue Origin CEO Bob Smith says the BE-4 has passed all of the technical tests required for ULA to sign onto a production contract.

    https://www.geekwire.com/2018/blue-origin-ceo-says-next-gen-4-rocket-engine-meets-technical-requirements/

    So, they did a full-duration, full-pressure burn and got the required stability, thrust, and I_sp?

    I would think those are the minimum technical requirements.

    And yet, the same article says the engine hasn't been run at full thrust or full mission duration. Go figure.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: HMXHMX on 04/21/2018 04:12 AM
    So I did have a few minutes to cobble together some captions.  In my haste I may have missed or mislabeled something, so corrections welcome.

    Great job! Minor nit. The arrow for the LOX High Pressure Discharge in Slide 2 is out of place. I've lightened up the image so that you can see the details better.

    So where is the LNG boost pump? Is it not needed?

    Ah, thanks, fixed.

    As for the LNG boost pump, like you I noted it wasn't there but don't know why.

    What if what you pointed out at the PB injector isn't actually it, but is buried downstream that within the gray cast structure? That preburner is inline with the main TP shaft and the pressures at the main discharge doesn't make sense...

    What if that jacket of cold LOX helps with something...

    Hmm...

    I'm thinking a kick pump is integrated into the inlet to the preburner assembly where you point to as the injector. The bolt patterns seem to indicate that there is a part bolted internally.

    There is already a LOX boost pump labeled, so I don't see any need for one at the inlet of the PB.  The PB will have an injector, a short combustion chamber (operating at perhaps 700°F±100) and a turbine to drive the single-shaft main propellant pumps.  The apparent PB length is just sufficient to provide space for those items.  Sometimes this cycle of engine will have a fuel kick pump (as is the case for the NK-33) but I don't see one in the BE-4 layout.

    I was insinuating that the LOX may be used to keep the methane at a lower temp to help prevent cavitation at the kick pump. Might just be a coincidence in packaging I just threw that idea out there, but it will definitely help keep the walls of the combustor side of the preburner cooler.

    You'll need a much higher fuel pressure at the PB than at the main chamber as stuff flows from high to low pressures. You need a good pressure difference between the above the turbine (which is kick pump pressure minus the delta p in the PB injector) to below (which is effectively manifold pressure to the main injector) The kick pump I was referring to being embedded in the PB assembly is the fuel kick pump. The fuel going to the regen chambers is main chamber pressure + main injector delta P + delta P in the cooling channels and pipes.

    I guess I'm a bit dubious about the "LOX cools LNG" idea but maybe Blue will "open up" about the design at some point and settle the question.  As for needing a fuel kick pump, that pump may be necessary in a more-or-less conventional injector (such as impinging streams or coaxial post) but if they use a pintle in the preburner – as was proposed for the TR-107 – then the fuel pressure drop is low (half that of the LOX pressure drop, typically).  The penalty for omitting the kick pump is that power to the whole TPA increases by perhaps 10-15%.  In that case, one main set of pumps at perhaps 2.5x discharge delta-p over main chamber Pc should suffice, taking into account turbine losses. The preburner would then operate at about 2x main chamber Pc.

    We lack a lot of necessary information, such as planned depth of throttle, and I'm not sure what the nominal Pc is – anyone know?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Steven Pietrobon on 04/21/2018 06:44 AM
    We lack a lot of necessary information, such as planned depth of throttle, and I'm not sure what the nominal Pc is – anyone know?

    13.4 MPa.

    https://arstechnica.com/science/2016/03/behind-the-curtain-ars-goes-inside-blue-origins-secretive-rocket-factory/
    Title: Re: Blue Origin's BE-4 Engine
    Post by: thammond on 04/25/2018 03:58 PM
    A few questions about the engine:

    There seem to be at least 4 different materials, or at least surface finishes - dark grey (lox boost pump), medium grey (fuel valve), light grey (fuel manifold), and shiny.  A special material for the pre-burner, turbine, and pre-burner exhaust makes sense, since these need to resist hot oxygen gas.  Are the others all different materials, or just different finishes?  If different materials, why?



    You can't infer material type from appearance.  Machining or polishing can cause shiny metal appearance, a sandblasted finish would have the medium to light grey appearance.  The dark grey could be an after heat treated appearance without any further finishing done to it such as sandblasting.

    The appearances of the various components could be due to different part requirements/specifications of individual parts along with different manufactures standard practices for finishing of parts.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: woods170 on 04/26/2018 06:58 AM
    A few questions about the engine:

    There seem to be at least 4 different materials, or at least surface finishes - dark grey (lox boost pump), medium grey (fuel valve), light grey (fuel manifold), and shiny.  A special material for the pre-burner, turbine, and pre-burner exhaust makes sense, since these need to resist hot oxygen gas.  Are the others all different materials, or just different finishes?  If different materials, why?



    You can't infer material type from appearance.  Machining or polishing can cause shiny metal appearance, a sandblasted finish would have the medium to light grey appearance.  The dark grey could be an after heat treated appearance without any further finishing done to it such as sandblasting.

    The appearances of the various components could be due to different part requirements/specifications of individual parts along with different manufactures standard practices for finishing of parts.

    Excellent post. Scale-modelers in particular are very aware of your fine summary.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: AncientU on 05/22/2018 04:21 PM
    Still* at 70%, 114s:
    Quote
    Ariane Cornell, Blue Origin: key for us in the next few months is continued BE-4 engine testing. Up to 70% thrust, 114-sec duration. #SpaceTechExpo
    https://twitter.com/jeff_foust/status/998961252184543233

    * 65%, 114s reported 3/12/18
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Lars-J on 05/22/2018 04:54 PM
    Still* at 70%, 114s:
    Quote
    Ariane Cornell, Blue Origin: key for us in the next few months is continued BE-4 engine testing. Up to 70% thrust, 114-sec duration. #SpaceTechExpo
    https://twitter.com/jeff_foust/status/998961252184543233

    * 65%, 114s reported 3/12/18

    They *still* haven't passed 70% thrust? They might be taking their "slow and steady" approach too far here. Or did the test stand destruction a while back rattle them that deeply?
    Title: Re: Blue Origin's BE-4 Engine
    Post by: AncientU on 05/22/2018 08:10 PM
    Soon.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: johnfwhitesell on 05/23/2018 01:46 PM
    Well this explains the mystery of why there is still no decision on Vulcan.  The competition is a paper engine and the race is still going...
    Title: Re: Blue Origin's BE-4 Engine
    Post by: Davidthefat on 05/23/2018 02:48 PM
    They might be pump head limited right now and have been waiting for a new iteration of the powerpack to be fabricated while still testing with the older revision.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: LouScheffer on 05/25/2018 02:04 PM
    They might be pump head limited right now and have been waiting for a new iteration of the powerpack to be fabricated while still testing with the older revision.
    Or perhaps testing revealed that some part X of the engine did not have the margins they'd like, so they can only test to 70% while they frantically (or graditum-ly) redesign and fabricate a new and better part X.
    Title: Re: Blue Origin's BE-4 Engine
    Post by: TrevorMonty on 05/25/2018 07:43 PM
    They've a lot to learn about this engine, destroying an engine by rushing test program will only slow them down. Slow methodical approach is still quickest way to get there. At some stage they also need to tear an engine apart to look at wear tear on components. Chances are first engine may not be taken to full thrust and duration just because of this.

    Title: Re: Blue Origin's BE-4 Engine
    Post by: Navier–Stokes on 07/11/2018 03:00 PM
    Quote from: https://twitter.com/jeff_foust/status/1017055593528426497
    Matsutomi: doing a lot of testing of the BE-4 engine, capable of going up to 200 seconds at a time. One aspect of the horizontal test stand is that the plume has created a “giant canyon” in front of the stand as plume erodes ground. #AIAAPropEnergy
    Quote from: https://twitter.com/jeff_foust/status/1017056479772278785
    Matsutomi: we’re targeting to complete BE-4 engine testing by the end of this year. #AIAAPropEnergy