Masten Space was working on a LOX/IPA (Isopropyl alcohol) 4000 lbf engine family called Katana. Did they finish? Or just change to other projects?
Quote from: Eric Hedman on 02/18/2018 12:45 amIf a replacement engine goes ahead, who pays for it for each flight, NASA or ESA?The Orion is a NASA program, and ESA is doing work on the Orion to offset their partner contribution for the ISS. So from that standpoint it would be NASA that pays for the new engines.
If a replacement engine goes ahead, who pays for it for each flight, NASA or ESA?
Since the ESM is build by ESA wouldn't it make more sense to let them deal with finding a replacement when the current hardware runs out? And instead of buying a drop-in replacement ESA can decide to do adjust the rest of the module.
Quote from: A_M_Swallow on 02/18/2018 10:03 amMasten Space was working on a LOX/IPA (Isopropyl alcohol) 4000 lbf engine family called Katana. Did they finish? Or just change to other projects?It might be arguable in principle to change to other hypergolic fuels, but changing to cryogenics would require total redesign of everything pretty much.
Quote from: speedevil on 02/18/2018 10:45 amQuote from: A_M_Swallow on 02/18/2018 10:03 amMasten Space was working on a LOX/IPA (Isopropyl alcohol) 4000 lbf engine family called Katana. Did they finish? Or just change to other projects?It might be arguable in principle to change to other hypergolic fuels, but changing to cryogenics would require total redesign of everything pretty much.If you're going to redesign the SM you might as well give Orion the same delta V as Apollo had while you're at it since it's mass is no longer constrained by Ares I.
If you're going to redesign the SM you might as well give Orion the same delta V as Apollo had while you're at it since it's mass is no longer constrained by Ares I.
Quote from: Patchouli on 02/19/2018 05:32 amIf you're going to redesign the SM you might as well give Orion the same delta V as Apollo had while you're at it since it's mass is no longer constrained by Ares I.For what purpose? In Apollo architecture, SM provided ΔV for LOI of full stack CSM/LM, as well as ΔV for TEI of CSM. In CxP architecture, Altair's hydrolox descent engine (would have) provided ΔV for full stack for LOI and SM would provide ΔV only for TEI of CSM. Altair's H2 descent engine (would have) had better ISP than Apollo SM engine, but H2 fuel required high volume due to low density, hence the very large descent stage on the Altair.With no lander design and no defined mission architecture, no one knows what Orion would even be used for. With no defined mission or architecture, it's impossible to define needed ΔV for Orion's SM. Apollo level amount of ΔV assumes Orion SM needs to cover full stack ΔV for LOI and ΔV for TEI of CSM. You need to define the architecture before you assign ΔV capacity of the SM.
Do we actually have a contract for additional ESMs or are they sunsetted after 3 (2 operational & 1 spare)?
ULA and Lockheed both seem very confident that ACES can support minimal boiloff for a few weeks at a time (and LM proposes this for their Mars architecture, though curiously retaining the ESM in-between), which is quite sufficient for Orion's requirements. And the benefit of using ACES specifically is that it would already exist and be almost entirely commercially paid for years before Orion is likely to fly. Sure, there are tons of other ways to build a similarly-performant ESM upgrade/replacement (even with cryogenics and/or refueling), but they will all have to be developed from scratch and will never approach the cost or flight heritage of a system already in commercial use at the time.
The SM was given to ESA because they wanted to stop flying cargo vehicles to the station....
Quote from: ReturnTrajectory on 02/19/2018 01:41 amThe SM was given to ESA because they wanted to stop flying cargo vehicles to the station....Why was ESA in a hurry to stop flying cargo to ISS?I can see why NASA would want ESA out of the cargo business, because that creates more demand for NASA's commercial-cargo program (and also happens to result in some of the ISS budget effectively being siphoned off to Orion/SLS).
AIUI ESA ran out of time. The supply chain for the ATV program was gone with hardware no longer being make or supported. So in order to continued doing ISS logistics meant that ESA have to do a new ATV program with new production lines. ESA did the much cheaper service module for the Orion capsule program instead as barter for ISS access.