The problem is they are only major airframe mfgs left in the US. Douglas, Grumman, GD, Convair (IIRC all capable of M2 airplane design and mfg) are all merged into either them or Northrup Grumman. If you want something winged and fast from a company with history of building one it's not much of a "competition" is it?
DARPA's pretty clearly not fixated on a winged design, so having "only" three competitors able to handle that design isn't a problem if a VTVL approach can also solve the problem--which it seems like it can. There's certainly enough options for one of them to bear the standard of VTHL or HTHL for this competition.
Moreover, as far as them being the only option, I think SNC, XCOR, or Virgin might have something to say about the ability of others outside of the Boeing/LockMart/N-G triumvirate to develop winged platforms. It's clearly not impossible to learn, nor is it the only option DARPA's interested in for this competition.
SpaceNews blurb on XS-1 program. States that DARPA "will consider 'manned, optionally manned, or unmanned concepts' for the plane" and that 100 reps attended industry day:DARPA’s XS-1 Experimental Spaceplane Call for Proposals Eyes a 2018 Liftoffhttp://www.spacenews.com/article/military-space/38138darpa%E2%80%99s-xs-1-experimental-spaceplane-call-for-proposals-eyes-a-2018
3. Question: In regard to critical technology risk reduction awards. Are you open tofunding upper stage propulsion, or are you only looking to fund spaceplane propulsionas part of Phase I?Answer: We are willing to transition relatively mature propulsion systems to supportPhase II/III. This can be with the spaceplane vehicle or with the upper stage.4. Question: Jess suggested that all subsystem technologies would be Governmentintellectual property (IP). If we propose a concept that employs subsystem technologiesdeveloped at private expense that we retain IP rights to, does that disadvantage ourproposal?Answer: The extent to which IP rights will potentially impact the Government’s abilityto transition technology will be evaluated. However, the inclusion of certain subsystemtechnologies developed at private expense does not necessarily mean that transitionwill be impeded. In general, if the Government pays for the development of a concept,the Government obtains Unlimited Rights. If you pay for its development theGovernment receives Limited/Restricted Rights. For concepts developed with mixedGovernment/private funding the Government receives Government Purpose Rights.See Defense Federal Acquisition Regulation Supplement (DFARS) Part 227 for moreinformation....10. Question: There are reusable ground launch booster systems in development that willlower the cost of space launch. What is the need for a Mach 10 spaceplane v.s a lowcost ground launched booster concept with a recoverable first stage?Answer: The XS-1 will be a low-cost recoverable booster concept. The rationale for theMach 10 requirement was provided in the presentations, including the potential todramatically lower launch costs. Winners of the Phase I contract will be eligible torecommend adjustments to the stated requirements....15. Question: How much of the system must be reflown? For example, is it acceptable ifthe proposed approach swaps out engine parts (pumps, bells), TPS, whole engines(solids), tanks, etc. within the time and cost constraints?Answer: XS-1 is a reusable vehicle. The removal and replacement of parts is acceptableas long as it meets the cost and time constraints for the program, and is fully justified inthe proposal.
My instinct is it will be VTVL and I have wondered how well this will accommodate the testing of hypersonic aircraft ideas, however I think that's a secondary issue.
Evaluation CriteriaIn Descending Order of Importance:• Overall Scientific and Technical Merit• Potential Contribution and Relevance to the DARPA Mission, includingPlans to Accomplish Technology Transition• Proposer’s Capabilities and/or Related Expertise• Cost Realism• Schedule Realism
They're going to give out four Phase 1s so long as they get enough good proposals. I'm almost positive you're going to get at least one VTVL, one VTHL, and possibly one either HTHL or AirLaunched/HL.
For all of them, he specifically mentioned the hypersonic testing could be done via a separate, deployable free-flyer. Basically you use this vehicle as a cheap booster to get you up to Mach 10, and then your actual test vehicle separates and does the hypersonic cruise flight demo, while your XS-1 booster slows down (either retrobraking or quick decelleration via TPS).
From the overview slides there's a graph of various launcher price per pound vs launcher mass to orbit. Falcon 9 is substantially below the trendline and does not appear to be involved in the calculation of the trendline. I estimate the trendline given in that chart to be roughly y = (x/1749)^-0.4476 where x is the mass to orbit in klb and y is the cost in k$ per lb. Note that the -0.4476 is a unitless constant. The significant of the number 1749 is that's the estimated mass to orbit (in klb) where the trendline reaches a thousand $ per lb. The metric equivalent works out to 4629 tonnes to orbit (~40 times SLS or Saturn V) having an estimated cost of 1 k$ / kg.Plugging in x=3000 klb we get y= 17 k$/lb, or a total launch cost of $52 million. I suspect they got the $5 million per flight goal by dividing this trendline value by 10 (an order of magnitude) and then rounding.-----In the contracting slides:QuoteEvaluation CriteriaIn Descending Order of Importance:• Overall Scientific and Technical Merit• Potential Contribution and Relevance to the DARPA Mission, includingPlans to Accomplish Technology Transition• Proposer’s Capabilities and/or Related Expertise• Cost Realism• Schedule RealismI'm surprised cost realism is a low priority.----------The trendline cost formula discussed above gives a cost of $156 million for 10 tonnes to orbit. I wonder if DARPA would be interested in funding Falcon 9R if it's a 10x improvement on trend (i.e. < $15M per 10 tonne launch) but doesn't meet the stated $5M goal. IMHO DARPA should have made the max cost a function of amount to LEO so that contractors have more flexibility as to sizing.
I might be wrong, but think for DARPA this program is more about developing the technology than about operational services.
However I'd suggest you re-check your "equivalent" in metric units. I make 1749 klb give a metric result that's 5.8x bigger. That's a large factor.
I can sort of see air launch but I'd say HTHL is the real long shot. I'd like to see Scaled and Xcorp have a go.
John, sorry for the pedantic nit, but it's XCOR (all caps, no "p"), not Xcor or Xcorp. They're picky about that. :-)
So much about there being no market for small payload RLVs...
Quote from: Elmar Moelzer on 11/25/2013 07:03 pmSo much about there being no market for small payload RLVs...Umm...that's still an open question isn't it? This is more a way of providing supply of small payload RLVs, doesn't prove there's actually demand for them (though that's obviously the hope!)~Jon
Quote from: jongoff on 11/25/2013 08:18 pmQuote from: Elmar Moelzer on 11/25/2013 07:03 pmSo much about there being no market for small payload RLVs...Umm...that's still an open question isn't it? This is more a way of providing supply of small payload RLVs, doesn't prove there's actually demand for them (though that's obviously the hope!)~JonWell DARPA seems to think so...