Author Topic: ULA SPACE 2015 Papers: Distributed Launch, ACES, "SMART" reuse, etc  (Read 31003 times)

Offline jongoff

  • Recovering Rocket Plumber/Space Entrepreneur
  • Senior Member
  • *****
  • Posts: 6807
  • Lafayette/Broomfield, CO
  • Liked: 3987
  • Likes Given: 1681
FYI, ULA had a few interesting papers they presented at the AIAA SPACE conference in Pasadena last week. I did a writeup on my blog of three of the more interesting ones, discussing their plans for their ACES stage, more details on how they'd do distributed launch, and on their SMART reuse concept.

Not too many surprises for those following them closely over the year, but the fact that they're now getting money to move many of these things forward is good.

http://selenianboondocks.com/2015/09/summary-of-some-ula-papers-from-aiaa-space-2015/

and here are links to all of the papers they presented at the conference:

http://www.ulalaunch.com/uploads/docs/Published_Papers/Commercial_Space/Business_Case_ForSpace_AIAASpace_2015.pdf -- George Sowers presentation on how ACES/Distributed Launch could enable things like space solar power (I'm politely skeptical on that particular application, but it provides useful details for other applications)

http://www.ulalaunch.com/uploads/docs/Published_Papers/Extended_Duration/Distributed-Launch-2015.pdf -- Great paper introducing distributed launch. For long-term ULA depot fans, there's a bit of review, but also some fresh new ideas. Will be cool to see how the ideas progresses going forward.

http://www.ulalaunch.com/uploads/docs/Published_Papers/Human_Rating/Commercial_Crew_Abort_System_AIAASpace_2015.pdf -- I didn't read this one in detail, but it's good to see that in the end all the BS spread about Atlas V's safety for crew launch back in the ESAS days has gone the way of the dinosaurs.

http://www.ulalaunch.com/uploads/docs/Published_Papers/Supporting_Technologies/LV_Recovery_and_Reuse_AIAASpace_2015.pdf -- A paper on SMART reuse. I think the approach will work, and am glad to see people trying different avenues. Just not sold on it being better than what SpaceX is doing with F9R first stage reuse. It'll be interesting to see where this goes.

http://www.ulalaunch.com/uploads/docs/Published_Papers/Upper_Stages/ACES-Stage_Concept-AIAASpace_2015.pdf -- Updates on their plans for the ACES stage.

Thoughts?

~Jon

Offline TrevorMonty

Thanks Jon for the links.

In regards to reuse on one AAIA videos they briefly showed a slide which had "autonomous engine recovery" on it. This was in 2025-35 time frame. I think it could be something like what Airbus are planning with Ariane 6.





Offline TrevorMonty

Just read reuse paper.
Their autonomous engine return system uses a couple of engine pods attached to a fuel tank/stage. I'm guessing the engine pods detach and fly back using a prop or jet engine. In theory this system should be scalable, add extra pods for heavier payloads. They a not quite as simple as bolt on SRBs but should be easier to attach/intergrate than SMART and Ariane 6 systems.

ULA are partnering with NASA on SMART system, this is win win for both companies.

The paper on distributed launch system (in orbit refuelling), described two versions, a Centuar and ACES version. If ULA can prove this system on the IVF Centuar first then there maybe a case for retiring D4H, before ACES is ready.



Offline jongoff

  • Recovering Rocket Plumber/Space Entrepreneur
  • Senior Member
  • *****
  • Posts: 6807
  • Lafayette/Broomfield, CO
  • Liked: 3987
  • Likes Given: 1681
Trever
Just read reuse paper.
Their autonomous engine return system uses a couple of engine pods attached to a fuel tank/stage. I'm guessing the engine pods detach and fly back using a prop or jet engine. In theory this system should be scalable, add extra pods for heavier payloads. They a not quite as simple as bolt on SRBs but should be easier to attach/intergrate than SMART and Ariane 6 systems.

ULA are partnering with NASA on SMART system, this is win win for both companies.

The paper on distributed launch system (in orbit refuelling), described two versions, a Centuar and ACES version. If ULA can prove this system on the IVF Centuar first then there maybe a case for retiring D4H, before ACES is ready.

That's not what I got from the paper--IIRC the SMART reuse is a single engine pod that uses a HIAD and mid air recovery. The ones they showed with the fly back boosters looks like an earlier idea that was eventually rejected.

Interesting point on using Centaur + Direct Launch possibly letting them retire Delta-IV early. Unfortunately, I'm not sure if this is the case because some of D4's payloads are large LEO satellites. But it's still an interesting idea.

~Jon

Offline TrevorMonty

Jon
You misunderstood my post.They are still doing SMART system with parachute and mid air recovery.

Autonomous Engine Recovery is their long term plan. Look at ULA technology timeline slide on the Business of Space video, 36min mark.

Offline jongoff

  • Recovering Rocket Plumber/Space Entrepreneur
  • Senior Member
  • *****
  • Posts: 6807
  • Lafayette/Broomfield, CO
  • Liked: 3987
  • Likes Given: 1681
Jon
You misunderstood my post.They are still doing SMART system with parachute and mid air recovery.

Autonomous Engine Recovery is their long term plan. Look at ULA technology timeline slide on the Business of Space video, 36min mark.

Huh. I'll have to ask them for clarification.

~Jon

Offline woods170

  • IRAS fan
  • Senior Member
  • *****
  • Posts: 12095
  • IRAS fan
  • The Netherlands
  • Liked: 18198
  • Likes Given: 12158
http://www.ulalaunch.com/uploads/docs/Published_Papers/Human_Rating/Commercial_Crew_Abort_System_AIAASpace_2015.pdf -- I didn't read this one in detail, but it's good to see that in the end all the BS spread about Atlas V's safety for crew launch back in the ESAS days has gone the way of the dinosaurs.

Perhaps good to remember that the mentioned BS was spread by the then NASA administrator: Mike Griffin.

Offline TrevorMonty

Jon
You misunderstood my post.They are still doing SMART system with parachute and mid air recovery.

Autonomous Engine Recovery is their long term plan. Look at ULA technology timeline slide on the Business of Space video, 36min mark.

Huh. I'll have to ask them for clarification.

~Jon
To make it more interesting the drawing in reuse paper fig 6, shows 2 engines per engine pod, ie 4xBE4. Should be capable of approx 35t to LEO, based on a 10-15% payload penalty which is what Airbus gave for their engine pod concept.

The engine pod idea is not totally new. Atlas 2 use to ditch 2 of its 3 engines 2 minutes in flight.

http://fas.org/spp/military/program/launch/atlas.htm
« Last Edit: 09/07/2015 07:49 am by TrevorMonty »

Offline Jim

  • Night Gator
  • Senior Member
  • *****
  • Posts: 37440
  • Cape Canaveral Spaceport
  • Liked: 21450
  • Likes Given: 428

ULA are partnering with NASA on SMART system, this is win win for both companies.


a.  NASA is not a company, it is a govt agency

b. NASA is not "partnering", it is just providing some support.
« Last Edit: 09/07/2015 12:23 pm by Jim »

Online sdsds

  • Senior Member
  • *****
  • Posts: 7201
  • “With peace and hope for all mankind.”
  • Seattle
  • Liked: 2050
  • Likes Given: 1962
I'm having trouble understanding Table 1 in the "Distributed Launch - Enabling Beyond LEO Missions" paper. It shows performance of various vehicles to various trajectories. One of the trajectories is shown as "20 km^2/sec^2" (note that's positive not negative 20) and is parenthetically labeled as "GSO". What is the meaning of this please?
« Last Edit: 09/08/2015 02:33 am by sdsds »
— 𝐬𝐝𝐒𝐝𝐬 —

Offline jongoff

  • Recovering Rocket Plumber/Space Entrepreneur
  • Senior Member
  • *****
  • Posts: 6807
  • Lafayette/Broomfield, CO
  • Liked: 3987
  • Likes Given: 1681
I'm having trouble understanding Table 1 in the "Distributed Launch - Enabling Beyond LEO Missions" paper. It shows performance of various vehicles to various trajectories. One of the trajectories is shown as "20 km^2/sec^2" (note that's positive not negative 20) and is parenthetically labeled as "GSO". What is the meaning of this please?

km^2/s^2 is the units for C3 energy. Where C3=0 is escape velocity. To back out the LEO velocity associated with a C3, you use the equation V_LEO = sqrt (V_escape^2 + C3). So with V_escape from LEO being ~11km/s, the V_LEO for a 20km^2/s^2 C3 is ~11.8km/s, which if you subtract off orbital velocity of ~7.8km/s gives you a delta-V for the maneuver of ~4.1km/s.

Basically they're saying that doing a direct insertion into GSO (ie your rocket does the GTO burn and then at apogee does the GSO circularization burn, plus any plane changes), it's the equivalent delta-V wise to doing a deep-space injection burn with a C3 of 20km^2/s^2 beyond escape velocity.

That make any sense? And anyone with stronger orbital dynamics fu, was my explanation right?  ;D

~Jon
« Last Edit: 09/08/2015 04:21 am by jongoff »

Offline TrevorMonty

My approach was to Google it. C3=0 earth escape 3.2km/s. C3=20 GSO 4.1km/s,
CS=80 Jupiter. 6.3km/s

Online sdsds

  • Senior Member
  • *****
  • Posts: 7201
  • “With peace and hope for all mankind.”
  • Seattle
  • Liked: 2050
  • Likes Given: 1962
That make any sense?

Yes, thanks! From your explanation I see that it takes approximately equivalent amounts of delta-v to reach either C3=20 or GSO. As atonement for being so dense about this I attempted to calculate the Hohmann transfer delta-v requirement. It looks to me like LEO to GSO requires ~3.9 km/s -- close enough anyway.
— 𝐬𝐝𝐒𝐝𝐬 —

Offline MP99



That make any sense?

Yes, thanks! From your explanation I see that it takes approximately equivalent amounts of delta-v to reach either C3=20 or GSO. As atonement for being so dense about this I attempted to calculate the Hohmann transfer delta-v requirement. It looks to me like LEO to GSO requires ~3.9 km/s -- close enough anyway.

GSO is indeed a negative C3.

If you were using a SEP stage to slowly circle out of LEO, the difference in energy would be the energy that the SEP would need to impart. Which is much more than the dV of an impulsive burn.

Impulsive burns at LEO have an Oberth benefit. That's on the GTO leg only, though. Little to none in the circularisation / plane changing near Apogee.

TL;DR we're used to seeing low dV numbers for GTO and similar burns because those are what chemical and short loiter times are ideal for.

Cheers, Martin

Online sdsds

  • Senior Member
  • *****
  • Posts: 7201
  • “With peace and hope for all mankind.”
  • Seattle
  • Liked: 2050
  • Likes Given: 1962
Regarding Table 2 in the same paper, it offers some tantalizing performance hints but omits some configurations. In particular, it does not provide performance for dual-launch Vulcan/Centaur. Reading between the lines, however, it seems clear this would provide better performance to every interesting orbit than DIV-H.

The implication of that is that ACES isn't required to meet any of the EELV requirements. True?
— 𝐬𝐝𝐒𝐝𝐬 —

Offline Space Ghost 1962

  • Senior Member
  • *****
  • Posts: 2780
  • Whatcha gonna do when the Ghost zaps you?
  • Liked: 2925
  • Likes Given: 2247
The implication of that is that ACES isn't required to meet any of the EELV requirements. True?

Yes.

The scope of Vulcan seems to have been set as a single stage development/change out (and surrounding facilities/mfr/CONOPs changes) gets you all of the capabilities of both EELVs. So you get all you currently require from risking just that. Smart.

Offline RocketmanUS

  • Senior Member
  • *****
  • Posts: 2226
  • USA
  • Liked: 71
  • Likes Given: 31
The implication of that is that ACES isn't required to meet any of the EELV requirements. True?

Yes.

The scope of Vulcan seems to have been set as a single stage development/change out (and surrounding facilities/mfr/CONOPs changes) gets you all of the capabilities of both EELVs. So you get all you currently require from risking just that. Smart.
Only if the customer will go for a two launch option. ACES or a wide body Centaur ( multi engine ) is needed to meet or exceed DIVH in a single launch on Vulcan.

Online sdsds

  • Senior Member
  • *****
  • Posts: 7201
  • “With peace and hope for all mankind.”
  • Seattle
  • Liked: 2050
  • Likes Given: 1962
Only if the customer will go for a two launch option.

The customer wants assurance that the payload will reach the intended orbit.

I love DIV-H, and am confident ULA can continue to operate it with 100% mission success. But it requires correct functioning of three booster cores. Distributed launch only requires two cores. Plus, if the first launch fails the customer's payload isn't put at risk.
— 𝐬𝐝𝐒𝐝𝐬 —

Offline jongoff

  • Recovering Rocket Plumber/Space Entrepreneur
  • Senior Member
  • *****
  • Posts: 6807
  • Lafayette/Broomfield, CO
  • Liked: 3987
  • Likes Given: 1681
Sdsds,
Distributed launch doesn't replace Delta-IVH for LEO missions. You'd still need ACES for that.

Jon

Offline Steven Pietrobon

  • Member
  • Senior Member
  • *****
  • Posts: 39215
  • Adelaide, Australia
    • Steven Pietrobon's Space Archive
  • Liked: 32735
  • Likes Given: 8178
Here's the performance chart from the ACES paper where I've annotated the payload masses in tonnes. I used the middle of the thick bars as the performance value. I also had to draw a new origin line for the mass to GTO so as to match up with the other performance lines.

One interesting think we can see is that reusing the first stage engine only reduced payload mass by 200 to 300 kg. Maximum performance is 14.8 t to GTO using the V564A.
Akin's Laws of Spacecraft Design #1:  Engineering is done with numbers.  Analysis without numbers is only an opinion.

Tags:
 

Advertisement NovaTech
Advertisement Northrop Grumman
Advertisement
Advertisement Margaritaville Beach Resort South Padre Island
Advertisement Brady Kenniston
Advertisement NextSpaceflight
Advertisement Nathan Barker Photography
0