So ...this contract finally started?
Quote from: pochimax on 11/16/2021 09:26 amSo ...this contract finally started? I don't think there's any sign that this is started?
Quote from: su27k on 11/17/2021 02:39 amQuote from: pochimax on 11/16/2021 09:26 amSo ...this contract finally started? I don't think there's any sign that this is started?If I'm understanding the information on the usaspending page right, it seems that there was a payout of $5.5M to SpaceX in May, and another $1.7M in July, plus a few hundred thousand dollars total in other months. (See the "Outlayed Amount" column in the table under Award History, in the "Federal Account Funding" tab.) So there's been a little bit of activity, but it's not much.
According to project officials, NASA did not provide SpaceX with authority to proceed in October 2020, as originally planned, due to funding constraints from operating under a continuing resolution and NASA having other funding priorities. As a result, there is a risk that the logistics mission may not be capable of supporting the Artemis III mission at the end of 2024.<snip>To try to mitigate this schedule risk, the project is also working with the Gateway program and the Advanced Exploration Systems division to obtain funding and with SpaceX on four special studies to prepare for the authority to proceed. For example, project officials said one study tasked SpaceX to develop an updated schedule to inform the launch readiness date for the initial mission. The project is also assessing whether it could tailor the current schedule and performance requirements if the authority to proceed continues to be delayed.
Quote from: tbellman on 11/17/2021 09:14 amQuote from: su27k on 11/17/2021 02:39 amQuote from: pochimax on 11/16/2021 09:26 amSo ...this contract finally started? I don't think there's any sign that this is started?If I'm understanding the information on the usaspending page right, it seems that there was a payout of $5.5M to SpaceX in May, and another $1.7M in July, plus a few hundred thousand dollars total in other months. (See the "Outlayed Amount" column in the table under Award History, in the "Federal Account Funding" tab.) So there's been a little bit of activity, but it's not much.This was discussed before, NASA is just giving them some study money without giving them authority to proceed, confirmed by GAO report:Quote from: GAO-21-306According to project officials, NASA did not provide SpaceX with authority to proceed in October 2020, as originally planned, due to funding constraints from operating under a continuing resolution and NASA having other funding priorities. As a result, there is a risk that the logistics mission may not be capable of supporting the Artemis III mission at the end of 2024.<snip>To try to mitigate this schedule risk, the project is also working with the Gateway program and the Advanced Exploration Systems division to obtain funding and with SpaceX on four special studies to prepare for the authority to proceed. For example, project officials said one study tasked SpaceX to develop an updated schedule to inform the launch readiness date for the initial mission. The project is also assessing whether it could tailor the current schedule and performance requirements if the authority to proceed continues to be delayed.
Don't know if this is the right place to ask this question, so please redirect if needed.I assume its feasible to send a Crew Dragon to the Gateway. Would it have to be with a FH or F9?
Understood. I came upon the idea while thinking of Orion. NASA likes to have a backup plan, they already had to send a few Astronauts that would have gone with Starliner on Crew Dragon.Neither Crew Rated Starship or Crewed Orion have flown to orbit as of yet. We just likes to keep something in our back pocket . . .I'm pretty sure CSS and Orion will fly successfully before 2024/5.
<snip>The requirement that SX now provide motel accommodations on DXL seems odd. It makes sense as a tug, but will they fill up the crew area with cargo when it is sent out to the Gateway? Or will they change the requirement down the line to make it a transit crew carrier as well? Just in case Orion is not ready?
Quote from: seb21051 on 11/28/2021 09:27 pmDon't know if this is the right place to ask this question, so please redirect if needed.I assume its feasible to send a Crew Dragon to the Gateway. Would it have to be with a FH or F9?<snip> I suspect you also need a new heat shield. At this point you have just re-invented Orion. Why bother? just send a crewed Starship.</snip>
Quote from: DanClemmensen on 11/29/2021 12:53 amQuote from: seb21051 on 11/28/2021 09:27 pmDon't know if this is the right place to ask this question, so please redirect if needed.I assume its feasible to send a Crew Dragon to the Gateway. Would it have to be with a FH or F9?<snip> I suspect you also need a new heat shield. At this point you have just re-invented Orion. Why bother? just send a crewed Starship.</snip>Dragon does not need a new heatshield. The current heatshield is already rated for lunar and Mars reentry into Earth's atmosphere.According to SpaceX; PICA-X, which is SpaceX's proprietary derivative of the PICA (Phenolic Impregnated Carbon Ablator) heatshield designed by NASA, can withstand reentries from "Lunar and Martian Velocities". Martian velocities being even higher, of course. PICA itself was used on the Stardust spacecraft which reentered at a speed of 46,500km/h. Apollo craft generally reentered at a speed of ~40,000km/h. An Earth reentry from Mars would, depending on how much energy you choose to expend, be between 49,000km/h-77,000km/h. Wired article.Another source is testimony that Garret Reisman himself offered, on page 4, where he says: Designed in partnership with NASA and fabricated by SpaceX, Crew Dragon’s heat shield is made of PICA-X, a high-performance improvement on NASA’s original phenolic impregnated carbon ablator (PICA). PICA-X is designed to withstand heat rates from a lunar return mission, which far exceed the requirements for a low Earth orbit mission.
Quote from: seb21051 on 11/28/2021 09:27 pmDon't know if this is the right place to ask this question, so please redirect if needed.I assume its feasible to send a Crew Dragon to the Gateway. Would it have to be with a FH or F9?I can think of four issues, but I don't have answers.* Delta V to get Crew Dragon to NRHO in the first place. FH can probably do this.* Crew Dragon Service module Delta V to rendezvous and dock with Gateway. Dragon XL will do this but probably expends most of it propellant, so a crew version of Dragon XL is not as simple as a the Dragon 2 twins.* Crew Dragon Service module Delta V to send Crew Dragon back to re-entry.* Crew Dragon heat shield for this high-velocity re-entry.I'm guessing at a minimum you need a new service module. I suspect you also need a new heat shield. At this point you have just re-invented Orion. Why bother? just send a crewed Starship.
Quote from: clongton on 11/29/2021 06:58 pmQuote from: DanClemmensen on 11/29/2021 12:53 amQuote from: seb21051 on 11/28/2021 09:27 pmDon't know if this is the right place to ask this question, so please redirect if needed.I assume its feasible to send a Crew Dragon to the Gateway. Would it have to be with a FH or F9?<snip> I suspect you also need a new heat shield. At this point you have just re-invented Orion. Why bother? just send a crewed Starship.</snip>Dragon does not need a new heatshield. The current heatshield is already rated for lunar and Mars reentry into Earth's atmosphere.According to SpaceX; PICA-X, which is SpaceX's proprietary derivative of the PICA (Phenolic Impregnated Carbon Ablator) heatshield designed by NASA, can withstand reentries from "Lunar and Martian Velocities". Martian velocities being even higher, of course. PICA itself was used on the Stardust spacecraft which reentered at a speed of 46,500km/h. Apollo craft generally reentered at a speed of ~40,000km/h. An Earth reentry from Mars would, depending on how much energy you choose to expend, be between 49,000km/h-77,000km/h. Wired article.Another source is testimony that Garret Reisman himself offered, on page 4, where he says: Designed in partnership with NASA and fabricated by SpaceX, Crew Dragon’s heat shield is made of PICA-X, a high-performance improvement on NASA’s original phenolic impregnated carbon ablator (PICA). PICA-X is designed to withstand heat rates from a lunar return mission, which far exceed the requirements for a low Earth orbit mission.Sorry, I'm just a casual observer, not a capsule designer. However, the fact that PICA-X material can be used to fabricate a heat shield for a Mars return does not by itself mean that the Crew Dragon heat shield has this capability. Why would SpaceX use a heavier shield than needed for re-entry from LEO on a craft that was designed specifically for an LEO mission?This is unreasonable unless SpaceX was already contemplating Lunar or Martian missions for Crew Dragon. Possibly they were: dearMoon was originally going to be a Crew Dragon launched by FH into a lunar free return trajectory, but I thought this had been abandoned early enough to allow the heat shield to be mass-reduced.
The one area of concern I see would be having sufficient life-support consumables for transit from LEO to NRHO and back. The longest free-flight for Dragon2 so far is the Inspiration4 mission at approximately 4-5 days.
Quote from: Cherokee43v6 on 11/29/2021 07:24 pmThe one area of concern I see would be having sufficient life-support consumables for transit from LEO to NRHO and back. The longest free-flight for Dragon2 so far is the Inspiration4 mission at approximately 4-5 days.Potentially, since the actual Inspiration4 mission duration was one hour short of three days.
ECLSS consumables ... last for 20 person-days