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The SSME as the engine for the Air Force RFP ?(LH2/O2 variant)

June 6, 2015

The SSME as the engine for the Air Force RFP ?

(A)(1) Cons; would be more expensive than The Delta-!V by far! unless….

(B)(1)This engine exists now and using an extent engine saves the Air force the 7 years and most of the $ 1 billion cost.(B)(2) SSME costs $70 Million each so 14 could be bought for $1 Billion however a block buy should be able to bring this price down(B)(3)An EELV with 2 SSME’s could possibly serve as a SLS CBC since 4 SSME’s are equivalent in thrust to one SRB however this means you would need 4 CBC’s!(B)(4) In the alternative you could have a SSME powered EELV with 4 SSME’s each but this monster would not any sense(B)(5) Three cores strapped to one another.with 6 SSME’s would be more expensive than Delta-IV it could be argued except that the air force along with NASA could do bulk purchases with use on the SLS and SLS CBC and an EELV

(C)(1) For the cost of the proposed Air Force RFP and a bulk buy for what would have been R&D costs you could perhaps purchase 20 engines(C)(2) The Air force RFP requests that the contractor engage in a private public partnership so Aerojet could fund the launch vehicle that would host the engine, this could be in partnership with a third party.(C)(3) If the engines are never used by the Air force they could be sold to NASA for SLS and the private/public partnership recovers its money, this works best if NASA agrees to mix some of these new engines with used engines from the shuttle program on the first three SLS missions.NASA would pay some money up front in order to gain from the block buy.An early NASA purchase would also increase the likely hood of a larger block buy to lower the per unit costs and that would increase the chances that an EELV would beat the Delta-IV in price.

(D)(1) The EELV and the EELV heavy would be human rated!(D)(2) The RS-25 could be incrementally evolvable to our proposed methane gell duel fuel RS-25

Methane SSME study


and the Methane gell Paper

EDIT 15:07 Hours

In the alternative Aerojet could comply with an Air Force RFP request for a private/public partnership by simply manufacturing its own white tail RS-25 to match an Air Force buy, this could be with an NASA agreement to fly them sooner rather than later and a third party partner funds the launch vehicle for the EELV.The existing RS-25/SSME test articles could used for integration studies for a clean sheet launcher and the NASA test stands could study propellent flow characteristics

If the Air Force stays with SpaceX and a future Vulcan vehicles and occasionally flies with the RS-25 vehicle then it would be important to design this EELV  if possible as a SLS CBC. It might be possible to with this industrial policy to make it economical to be flying three engines and three launch vehicles and this leverages the NASA SLS need for a CBC to better inform Air Force purchases decisions.NASA on the other hand by agreeing to fly a mix of old and new engines on the first 3 SLS vehicles enables aerojet and the air force to leverage funds to develop the launch vehicles

 Buying 28 new engines over 4 to 5  years and halving the price would be another method for aerojet to contribute skin in the game with the understanding that RS-25 to RS-25E becomes an incremental effort that NASA planned to fund anyhow.A mass purchase of an incrementally evolved RS-25 to RS-25E could be done with the existing SLS funding and the Air Force benefits to from the lower cost RS-25E. with a production run and the SSME test article engine we could also test fire low levels of methane/LNG gelled in LH2, I believe one  of the test stands has been modified to handle this type of propellent but we would need to add this capability to the SSME test stand.In the end all or most of the air force SSME’s might be sold to NASA but the RS-25E could find its way on a launch vehicle with greater frequency as it comes on line for Air Force use


In regards to a third party launch vehicle intregreter orbital comes to mind!  We do not suggest giving up the new russian engine or Antares but a RS-25 powered vehicle could get commercial cargo (Cygnus) to a Lagrange point space station.orbital and aerojet could sell this as another means to NASA to lower RS-25 unit costs to SLS.I am researching this right now but the SSME’s are very light,The RS-25E will be a bit heavier but this would a great quality to have for engine recovery via helicopter in air retrieval!“>


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