The telling time will come, unless I missed it, of ATK being told to start making the 1sts set of SRBs after the current casings are exhausted. Another indicator is the number of SSMEs they have available. Will they last longer than he casings?
Note that the new RS-25Es aren't expected to be built until 2027. 4 flights in 9 years, assuming no delays in production restart.
Quote from: brickmack on 12/16/2016 12:24 amNote that the new RS-25Es aren't expected to be built until 2027. 4 flights in 9 years, assuming no delays in production restart.I don't believe that this still holds true. The most recent EM mission schedule has at least 8 missions by 2029, which would necessitate an earlier production start to RS-25E.
Quote from: Khadgars on 12/16/2016 03:25 pmQuote from: brickmack on 12/16/2016 12:24 amNote that the new RS-25Es aren't expected to be built until 2027. 4 flights in 9 years, assuming no delays in production restart.I don't believe that this still holds true. The most recent EM mission schedule has at least 8 missions by 2029, which would necessitate an earlier production start to RS-25E.Realistically, the 4th would be 2025 at earliest and 2027 would be the fifth, which would necessitate RS25 production. But of course you'd need to start production several years earlier.
"After its maiden flight with a pilot in tow, NASA hopes to begin annual flights to the lunar orbit starting in 2023. All but one of the eight planned missions in NASA's latest flight manifest will be dedicated to the assembly of the mini-International Space Station in lunar orbit. Various pieces of the future habitat will be hitchhiking on each Orion flight."
I said realistically. I'd bet hard cash EM2 isn't launching until 2023 at earliest, then launches every two years after that is most realistic. Which means you can push off RS25 production for several more years.NASA "looking at" something and NASA realistically doing something are two different things.
The one capability that impacts on flight path design of EM-2 is mission duration for the Orion. The flight path needs to be able to be shortened if problems with the mission duration capabilities are found.
how to arrange to approach the moon on both passes
Quote from: Khadgars on 12/16/2016 03:25 pmQuote from: brickmack on 12/16/2016 12:24 amNote that the new RS-25Es aren't expected to be built until 2027. 4 flights in 9 years, assuming no delays in production restart.I don't believe that this still holds true. The most recent EM mission schedule has at least 8 missions by 2029, which would necessitate an earlier production start to RS-25E.This information comes from NASAs defense for sole-sourcing RS-25 from Aerojet. That was less than a year ago, and stated that not only would the 5th flight be in 2027, but that they didn't think Aerojet or any other company could deliver the engines faster because restarting the production line will take so long
"“In order to meet SLS Program flight manifest requirements, production of RS-25 flight engines will be concurrent with the engine recertification effort. The number of new flight engine: to be included as part of this action is six (6)"