Author Topic: DARPA Experimental Spaceplane 1 (XS-1) Program  (Read 278477 times)

Offline envy887

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Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #760 on: 11/01/2017 12:56 PM »
Speculative. This isnít the most complex of programs and is entirely doable within the timeframe given by a company like Boeing and their experience in these areas.
Sure they do, so had Lockheed with the X33 and then we had Constellation and all the other "wonderful" projects of the past 30 years. All had cost and time overruns.
The problem is that the timeframe falls right into the ballpark time where a new administration would cancel it. Has happened before.
Personally, I am also underwhelmed by the concept, considering what SpaceX and Blue are doing right now. If this was an SSTO, it would be interesting but as it is, I am not at all excited.

One of the drawbacks of the SpaceX and Blue concepts is the low staging velocity dictating a large and expensive upper stage. I like the idea of faster staging and glideback allowing a smaller upper stage, although I think Boeing's implementation has about 0% chance of hitting the $5M cost and 1 day turnaround targets. LH2 and SSME were both terrible choices, IMO.

I would like to see what a similar all-methalox vehicle would look like, e.g. a single BE-4 booster and single Broadsword upper stage.

Online whitelancer64

Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #761 on: 11/01/2017 01:02 PM »
I think Darpa wants to use mach10 capability for highspeed testing of other vehicles eg scamjet missiles.

Sent from my SM-T810 using Tapatalk

Keep in mind that Mach 10 is peak velocity at MECO, not speed in level flight.
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Online Elmar Moelzer

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Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #762 on: 11/01/2017 02:55 PM »
One of the drawbacks of the SpaceX and Blue concepts is the low staging velocity dictating a large and expensive upper stage.
If the system was optimized for such a small payload, I am pretty sure the staging velocity could be higher (and the upper stage smaller). IIRC, a F9 first stage by itself is almost SSTO capable. So they should be able to do a Mach 10 MECO quite easily with such a small load on top and still have enough fuel for RTLS. I would assume that they could even remove a few Merlins from the first stage, but I may be wrong with that.

Offline john smith 19

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Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #763 on: 11/02/2017 10:01 AM »
If the system was optimized for such a small payload, I am pretty sure the staging velocity could be higher (and the upper stage smaller). IIRC, a F9 first stage by itself is almost SSTO capable. So they should be able to do a Mach 10 MECO quite easily with such a small load on top and still have enough fuel for RTLS. I would assume that they could even remove a few Merlins from the first stage, but I may be wrong with that.
Quite possibly.

The problem is not the going up. It's the coming down, as SX realized some years ago.
You're looking at something like 10x the KE and PE per Kg of mass from LEO that you are from their staging velocities and altitudes.

That's what's killed talk of a reusable F9 US. 
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Online Elmar Moelzer

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Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #764 on: 11/02/2017 05:39 PM »
If the system was optimized for such a small payload, I am pretty sure the staging velocity could be higher (and the upper stage smaller). IIRC, a F9 first stage by itself is almost SSTO capable. So they should be able to do a Mach 10 MECO quite easily with such a small load on top and still have enough fuel for RTLS. I would assume that they could even remove a few Merlins from the first stage, but I may be wrong with that.
Quite possibly.

The problem is not the going up. It's the coming down, as SX realized some years ago.
You're looking at something like 10x the KE and PE per Kg of mass from LEO that you are from their staging velocities and altitudes.

That's what's killed talk of a reusable F9 US.
Was not saying that they should/ could do SSTO with the first stage, but they could certainly do Mach 10 for staging maybe still do an RTLS with such a small payload and second stage on top of it.

Offline envy887

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Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #765 on: 11/02/2017 06:50 PM »
If the system was optimized for such a small payload, I am pretty sure the staging velocity could be higher (and the upper stage smaller). IIRC, a F9 first stage by itself is almost SSTO capable. So they should be able to do a Mach 10 MECO quite easily with such a small load on top and still have enough fuel for RTLS. I would assume that they could even remove a few Merlins from the first stage, but I may be wrong with that.
Quite possibly.

The problem is not the going up. It's the coming down, as SX realized some years ago.
You're looking at something like 10x the KE and PE per Kg of mass from LEO that you are from their staging velocities and altitudes.

That's what's killed talk of a reusable F9 US.
Was not saying that they should/ could do SSTO with the first stage, but they could certainly do Mach 10 for staging maybe still do an RTLS with such a small payload and second stage on top of it.

I don't think it could. If you stage at 3,000 m/s, you need over 3,000 m/s just to null downrange velocity of the booster (while carrying entry and landing fuel). I get the F9 booster as having 3,300 m/s available at that point, which is not enough considering entry and landing need over 1,000 m/s. It's almost easier to just send the booster on into orbit than to RTLS from Mach 10.

XS-1 gets around this by using the atmosphere to slow down, turn around, and glide back empty. This should work if it flies a depressed trajectory, just exiting the atmosphere long enough for the upper stage to get to orbit. With a fairly thrusty upper stage (e.g. 35 klbf Broadsword), this takes ~130 seconds, during which time the booster will coast ~390 km downrange. This can be less if the upper stage eats some of the gravity losses.

Offline john smith 19

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Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #766 on: 11/02/2017 07:33 PM »

I don't think it could. If you stage at 3,000 m/s, you need over 3,000 m/s just to null downrange velocity of the booster (while carrying entry and landing fuel). I get the F9 booster as having 3,300 m/s available at that point, which is not enough considering entry and landing need over 1,000 m/s. It's almost easier to just send the booster on into orbit than to RTLS from Mach 10.

XS-1 gets around this by using the atmosphere to slow down, turn around, and glide back empty. This should work if it flies a depressed trajectory, just exiting the atmosphere long enough for the upper stage to get to orbit. With a fairly thrusty upper stage (e.g. 35 klbf Broadsword), this takes ~130 seconds, during which time the booster will coast ~390 km downrange. This can be less if the upper stage eats some of the gravity losses.
How tough this problem is depends on how long the design stays at M10 and at what altitude. It's a VTO so presumably it will be at less tahn 1/2 SL pressure by the time it breaks M1 and starts to go horizontal (or strictly speaking into a non-vertical climb).

With a fast enough climb and acceleration they could go with an ablative TPS and have minimal burn off.

Interesting small detail about the Ames TPS PICA and SIRCA. SIRCA can be mfg not only as rigid sections but also a stiff "spongy" like layer. This proved exceptionally handy for the back shell of the Curiosity rover aeroshell. This had lots of "closeouts" IE doors, panels, holes for cables. With rigid TPS you can put a panel on the door, but what about the area around it? The hinges? The frame?
Being flexible meant you could lay a layer over the door and then cut the outline of the door into it. Simple, fast and effective.

Control surfaces would probably be difficult but a sort of "glove" should work there.
« Last Edit: 11/02/2017 10:14 PM by john smith 19 »
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Offline TrevorMonty

Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #767 on: 11/02/2017 10:05 PM »
I don't think M10 requirement was for normal orbital launches more for possible testing. Operational separation velocity is more likely to be in M5-10 region.


Online Elmar Moelzer

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Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #768 on: 11/03/2017 02:36 AM »
Was not saying that they should/ could do SSTO with the first stage, but they could certainly do Mach 10 for staging maybe still do an RTLS with such a small payload and second stage on top of it.

I don't think it could. If you stage at 3,000 m/s, you need over 3,000 m/s just to null downrange velocity of the booster (while carrying entry and landing fuel). I get the F9 booster as having 3,300 m/s available at that point, which is not enough considering entry and landing need over 1,000 m/s. It's almost easier to just send the booster on into orbit than to RTLS from Mach 10.
The Falcon 9 1.1 first stage by itself has a DeltaV of at least 8300 m/s according to my calculations.
Of course, then you need to add the weight of an upper stage plus its fuel. Let's assume some 20 tons of mass for that (dry weight of a conservative 3,000 kg plus the payload of 1,000 kg and the rest is fuel).
With that I still get a Delta V of at least 7500 m/s and that is assuming it carries the fueled second stage all the way back too. So it would still have 1500 m/s for the rest.
Things may be looking even better with the latest versions of Falcon 9 and even more with block 5.
I might be wrong somewhere, but from this back of the envelope calculation, it still sounds plausible to me.

Offline su27k

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Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #769 on: 11/03/2017 03:03 AM »
I don't think it could. If you stage at 3,000 m/s, you need over 3,000 m/s just to null downrange velocity of the booster (while carrying entry and landing fuel). I get the F9 booster as having 3,300 m/s available at that point, which is not enough considering entry and landing need over 1,000 m/s. It's almost easier to just send the booster on into orbit than to RTLS from Mach 10.

XS-1 gets around this by using the atmosphere to slow down, turn around, and glide back empty. This should work if it flies a depressed trajectory, just exiting the atmosphere long enough for the upper stage to get to orbit. With a fairly thrusty upper stage (e.g. 35 klbf Broadsword), this takes ~130 seconds, during which time the booster will coast ~390 km downrange. This can be less if the upper stage eats some of the gravity losses.

We'll see if glideback can really do this, there're papers comparing glideback with boostback and flyback, pretty much every time the glideback staging speed is the lowest among the 3.

Offline envy887

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Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #770 on: 11/04/2017 01:44 AM »
Was not saying that they should/ could do SSTO with the first stage, but they could certainly do Mach 10 for staging maybe still do an RTLS with such a small payload and second stage on top of it.

I don't think it could. If you stage at 3,000 m/s, you need over 3,000 m/s just to null downrange velocity of the booster (while carrying entry and landing fuel). I get the F9 booster as having 3,300 m/s available at that point, which is not enough considering entry and landing need over 1,000 m/s. It's almost easier to just send the booster on into orbit than to RTLS from Mach 10.
The Falcon 9 1.1 first stage by itself has a DeltaV of at least 8300 m/s according to my calculations.
Of course, then you need to add the weight of an upper stage plus its fuel. Let's assume some 20 tons of mass for that (dry weight of a conservative 3,000 kg plus the payload of 1,000 kg and the rest is fuel).
With that I still get a Delta V of at least 7500 m/s and that is assuming it carries the fueled second stage all the way back too. So it would still have 1500 m/s for the rest.
Things may be looking even better with the latest versions of Falcon 9 and even more with block 5.
I might be wrong somewhere, but from this back of the envelope calculation, it still sounds plausible to me.

You appear to be missing gravity and drag losses on the first stage, which take all of that 1500 m/s and maybe a little more.

XS-1 is supposed to put 1,300 kg to SSO, so lets try to match that with F9 staging at 3,000 m/s. Orbital velocity is about 7750 m/s, and it gains nothing from rotation of the Earth, so the upper stage needs 4750 m/s. With a dry stage mass fraction of 10%, the upper stage, payload, and propellant are about 9 tonnes (varies slightly depending on the fuel choice, but not enough to matter here).

The F9 v1.2 booster is 27 tonnes dry and holds 436 tonnes of kerolox, and with the 9 t upper stage total GLOM is 471 tonnes and mass at MECO (~4600 m/s with drag and grav losses) is 101 tonnes. Mass after separation is 92 tonnes, and after boostback (3350 m/s) is 34 tonnes. The 7 tonnes of remaining fuel are enough for about 1/2 of the entry burn, so this won't work, although we're pretty close.

Online Elmar Moelzer

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Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #771 on: 11/05/2017 08:05 AM »
Was not saying that they should/ could do SSTO with the first stage, but they could certainly do Mach 10 for staging maybe still do an RTLS with such a small payload and second stage on top of it.

I don't think it could. If you stage at 3,000 m/s, you need over 3,000 m/s just to null downrange velocity of the booster (while carrying entry and landing fuel). I get the F9 booster as having 3,300 m/s available at that point, which is not enough considering entry and landing need over 1,000 m/s. It's almost easier to just send the booster on into orbit than to RTLS from Mach 10.
The Falcon 9 1.1 first stage by itself has a DeltaV of at least 8300 m/s according to my calculations.
Of course, then you need to add the weight of an upper stage plus its fuel. Let's assume some 20 tons of mass for that (dry weight of a conservative 3,000 kg plus the payload of 1,000 kg and the rest is fuel).
With that I still get a Delta V of at least 7500 m/s and that is assuming it carries the fueled second stage all the way back too. So it would still have 1500 m/s for the rest.
Things may be looking even better with the latest versions of Falcon 9 and even more with block 5.
I might be wrong somewhere, but from this back of the envelope calculation, it still sounds plausible to me.

You appear to be missing gravity and drag losses on the first stage, which take all of that 1500 m/s and maybe a little more.

XS-1 is supposed to put 1,300 kg to SSO, so lets try to match that with F9 staging at 3,000 m/s. Orbital velocity is about 7750 m/s, and it gains nothing from rotation of the Earth, so the upper stage needs 4750 m/s. With a dry stage mass fraction of 10%, the upper stage, payload, and propellant are about 9 tonnes (varies slightly depending on the fuel choice, but not enough to matter here).

The F9 v1.2 booster is 27 tonnes dry and holds 436 tonnes of kerolox, and with the 9 t upper stage total GLOM is 471 tonnes and mass at MECO (~4600 m/s with drag and grav losses) is 101 tonnes. Mass after separation is 92 tonnes, and after boostback (3350 m/s) is 34 tonnes. The 7 tonnes of remaining fuel are enough for about 1/2 of the entry burn, so this won't work, although we're pretty close.
I think that you are overemphasizing the effect of drag and gravity losses, as we are not going all the way to orbit (though from what I understand, the booster gets to handle most of that).
Koreasat was roughly Mach 8 at stage separation. Granted that landed downrange on an ASDS. But then this was carrying a much heavier (8 times as heavy according to your numbers) upper stage and payload than it would have to for XS1.
Also, lets not forget that these values are for 1.2 and not for Block 5. Also lets not forget that the Mach 10 is not required for routine operation but only has to be demonstrated. So, ever optimistic me, still thinks that it would work, though as you say, it may be cutting it close for Mach 10 separation. Though I am not sure whether the Mach 10 demo allows for downrange landing instead of RTLS. I might have missed it, but is there anything know about the contractual requirements for that?

Online russianhalo117

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Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #772 on: 12/13/2017 04:32 AM »
XS-1 (now renamed XS-P for Experimental Spaceplane Program) program of the Defense Advanced Research Projects Agency (DARPA).
« Last Edit: 12/13/2017 04:33 AM by russianhalo117 »

Offline john smith 19

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Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #773 on: 01/03/2018 08:16 AM »
XS-1 (now renamed XS-P for Experimental Spaceplane Program) program of the Defense Advanced Research Projects Agency (DARPA).
This seems to be the first time it's called XS-P rather than XS-1, which was the formal name of the vehicle that broke the sound barrier.

http://spacenews.com/darpa-aims-to-disrupt-national-security-space-business/

DARPA are saying this really is happening and hardware is going to actually get built. They are also saying if it does Boeing will decide if they want to develop it as a service that they can then sell back to the DoD and (presumably) other customers.

This is very loosely the model of the X33 programme, which ended so badly. Time will tell if any lessons were learned or if (yet again) the USG has been played like "A banjo at an Ozark hoedown." :(
BFS. The worlds first Methane fueled FFORSC engined CFRP structured A380 sized aerospaceplane tail sitter capable of flying in Earth and Mars atmospheres. BFR. The worlds biggest Methane fueled FFORSC engined CFRP structured booster for BFS. First flight to Mars by end of 2022. Forward looking statements. T&C apply. Believe no one. Run your own numbers. So, you are going to Mars to start a better life? Picture it in your mind. Now say what it is out loud.

Offline Star One

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DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #774 on: 01/03/2018 10:21 AM »
XS-1 (now renamed XS-P for Experimental Spaceplane Program) program of the Defense Advanced Research Projects Agency (DARPA).
This seems to be the first time it's called XS-P rather than XS-1, which was the formal name of the vehicle that broke the sound barrier.

http://spacenews.com/darpa-aims-to-disrupt-national-security-space-business/

DARPA are saying this really is happening and hardware is going to actually get built. They are also saying if it does Boeing will decide if they want to develop it as a service that they can then sell back to the DoD and (presumably) other customers.

This is very loosely the model of the X33 programme, which ended so badly. Time will tell if any lessons were learned or if (yet again) the USG has been played like "A banjo at an Ozark hoedown."

Is there any reason you are making this comparison at this early stage? It makes it look like you have a desire to put a negative spin on things. You yourself admit that the similarities are weak at best.
« Last Edit: 01/03/2018 10:24 AM by Star One »

Offline john smith 19

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Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #775 on: 01/03/2018 04:40 PM »

Is there any reason you are making this comparison at this early stage? It makes it look like you have a desire to put a negative spin on things. You yourself admit that the similarities are weak at best.
Firstly it's not early, it's the 3rd phase of the programme, which is further than most DARPA efforts have got in this area.

Secondly Boeing ditched Masten as an engine supplier. They've gone from a smallish agile mfg with a reputation for getting things done for a ponderous conglomerate most of whose business is in solids who are going to cobble together a couple of more-or-less SSME's from spare parts that are 40+ years old.
That sounds an awful lot like a Government contractor playing "government contractor" games, using "bid candy" to win the contract. That alone would set my alarm bells ringing.

Thirdly both Boeing and LM are deeply  invested in BAU through ULA and the EELV programme. LM's defense of their EELV business made them perfectly happy to make completely unjustified commitments on pricing for the follow on Venture Star vehicle. They knew they would never have to honor them as X33 would never fly, and it didn't.  The other competitors were more conservative, suggesting they actually wanted to fly something.

Fourthly this vehicle looks like it was designed to maximum performance rather than minimum cost and/or minimum turnaround time criteria. It looks like Boeing designed it to try to go SSTO but it's simply not going to do that and it simply does not need that performance. Shuttle had complex wings because if its stupid "orbit the planet and land at the same launch site" requirement. IOW a 2000mile+ cross range. VTOHL design have to be strong like a rocket (top to bottom) and strong like an airplane (landing gear to top of tail) unlike any "single mode" vehicle IE VTOL or HTOL

Fifthly if SpaceX has taught any lessons it's that a)Scaling up is fairly cheap with the right design and b)Propellant is very cheap. c)For a reusable stage designed for enough reuses the re-use mission cost drops to the refurb cost + propellant+upper stage cost.
So spending too much to reduce booster vehicle size when you can just add propellant is pointless. Maximum energy propellant is probably unnecessary and you should do everything possible to simplify the US by making the altitude/attitude/speed "box" the US is released from as tight as possible. There has been no word on what the US will be. 

Time will tell if I'm being a pessimist or of this is just another (of many) "funds transfer" programmes to hand a bag of taxpayers cash to a US corporation, give some of its more junior staff some real life design experience and declare "Sorry, it just can't be done."  :(

BTW I've met Jess Sponable and I liked him a lot. I really want him, DARPA and Boeing to succeed in this. However "Want to succeed" does not man "Turn off critical thinking faculties,"  and that engine change of Boeing's looks a lot like a "Bait and switch" move.  It does not inspire trust.
« Last Edit: 01/03/2018 04:49 PM by john smith 19 »
BFS. The worlds first Methane fueled FFORSC engined CFRP structured A380 sized aerospaceplane tail sitter capable of flying in Earth and Mars atmospheres. BFR. The worlds biggest Methane fueled FFORSC engined CFRP structured booster for BFS. First flight to Mars by end of 2022. Forward looking statements. T&C apply. Believe no one. Run your own numbers. So, you are going to Mars to start a better life? Picture it in your mind. Now say what it is out loud.

Offline Space Ghost 1962

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Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #776 on: 01/03/2018 05:04 PM »
My read is that the program is being redirected unsubtlely. It provides a means for a response to certain threats, at a different scale than intended, and compromises on the economics of operation to get there.

You might be able to apply Shuttle related content to do this. But all the baggage comes along as well. Unlike Masten's approach, which I much preferred/recommended.

Boeing has immense reputation/skills/capability. The trouble they face is in choosing "what not to do", and "why not to do it".

Offline john smith 19

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Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #777 on: 01/03/2018 06:17 PM »
My read is that the program is being redirected unsubtlely. It provides a means for a response to certain threats, at a different scale than intended, and compromises on the economics of operation to get there.
But this was never really designed as an operational vehicle, more a way of learning how to do an operational vehicle, IE an X-Plane, or a template. :(

On the upside that does suggest there is motivation (and presumably funding) to make this happen, which seems to have been lacking in previous efforts.
Quote from: Space Ghost 1962
You might be able to apply Shuttle related content to do this. But all the baggage comes along as well. Unlike Masten's approach, which I much preferred/recommended.
And the Shuttle design has a lot of baggage.
Quote from: Space Ghost 1962
Boeing has immense reputation/skills/capability. The trouble they face is in choosing "what not to do", and "why not to do it".
In "The Mythical Man Month" FE Brookes called it the "Second System Effect." The desire to use all those clever (but not quite clever enough) ideas that didn't make it into the first system a designer builds.

The two things I noticed about the Shuttle were a)Lack of design co-ordination between systems and b)the tendency to design "point" solutions instead of using existing components to design out a  problem.

Classic examples of this were the 5000lb  of LO2/LH2 left in the MPS plumbing that had been hauled up the gravity well was simply dumped (because it seems no one was responsible for it, or finding a use for it), and the Ammonia Boiler system, that only ran for a very short period of the flight and required high purity, completely water free Ammonia to function.
BFS. The worlds first Methane fueled FFORSC engined CFRP structured A380 sized aerospaceplane tail sitter capable of flying in Earth and Mars atmospheres. BFR. The worlds biggest Methane fueled FFORSC engined CFRP structured booster for BFS. First flight to Mars by end of 2022. Forward looking statements. T&C apply. Believe no one. Run your own numbers. So, you are going to Mars to start a better life? Picture it in your mind. Now say what it is out loud.

Offline TrevorMonty

Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #778 on: 01/03/2018 10:59 PM »
Boeing were partnering with Blue NOT Masten who competiting for same contract. With Blue they had option of proven BE3 or maybe BE4. Why they choose RS25 over 5x BE3 we may never know, but RS25 has proved its self as reuseable engine on shuttle.

There is nothing wrong with VTOHL. Its a very low risk approach for Boeing who are experts at HL. May not scale but that doesn't matter for this LV.

Offline john smith 19

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Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #779 on: 01/03/2018 11:42 PM »
Boeing were partnering with Blue NOT Masten who competiting for same contract. With Blue they had option of proven BE3 or maybe BE4. Why they choose RS25 over 5x BE3 we may never know, but RS25 has proved its self as reuseable engine on shuttle.
As Blue proved themselves as bid candy on this contract. In fact given their size relative to the Masten Broadsword it's even more surprising they were dropped. BE-4 is actually in the vacuum thrust range of the SSME.

Didn't recycling the NK33's from Russia teach people that re-building 40+ YO rocket engines (or rather assembling a couple from 40+YO parts) is to put it very mildly, problematical?
Quote from: TrevorMonty
There is nothing wrong with VTOHL. Its a very low risk approach for Boeing who are experts at HL. May not scale but that doesn't matter for this LV.
It always amused me that Shuttle had a stack mass of about 4000 000lbs and a payload (in the bay) of 55 000. IE it had the performance of an SSTO and the mass of a multi stage ELV. IOW the worst of both worlds.  :( It was however the only way to deliver a vehicle on the budget without going Biemese or Triemese.

For a lot of people the lesson to learn was "Don't do it this way, if you can possibly avoid it."
« Last Edit: 01/03/2018 11:55 PM by john smith 19 »
BFS. The worlds first Methane fueled FFORSC engined CFRP structured A380 sized aerospaceplane tail sitter capable of flying in Earth and Mars atmospheres. BFR. The worlds biggest Methane fueled FFORSC engined CFRP structured booster for BFS. First flight to Mars by end of 2022. Forward looking statements. T&C apply. Believe no one. Run your own numbers. So, you are going to Mars to start a better life? Picture it in your mind. Now say what it is out loud.

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