Total Members Voted: 173
Voting closed: 06/30/2014 11:30 pm
This includes any crewed test flights to orbit, right?
I thought a man-rated Delta IV was/is out of the question?Both with the current RS-68 and structural margins being below 1.4.
Quote from: AS-503 on 01/07/2014 11:26 pmI thought a man-rated Delta IV was/is out of the question?Both with the current RS-68 and structural margins being below 1.4.Not out of the question. It's good enough for incredibly expensive and incredibly important national security assets (upon which millions of lives depend). We used to launch men on converted ICBMs, remember?
Quote from: Robotbeat on 01/07/2014 11:29 pmQuote from: AS-503 on 01/07/2014 11:26 pmI thought a man-rated Delta IV was/is out of the question?Both with the current RS-68 and structural margins being below 1.4.Not out of the question. It's good enough for incredibly expensive and incredibly important national security assets (upon which millions of lives depend). We used to launch men on converted ICBMs, remember?While I agree with all of your points, sadly they are not relevant to NASA's standards for man-rated.Historically speaking Gemini pulled about 7gs on the way up (steep trajectory) on it's converted ICBM with "black zones" almost the entire way to orbit (even including sitting on the pad). Yes, I remember, but are you really arguing for a return to this type of (non) risk-aversion?After the two STS accidents, it is a safe assumption that all manned flights (on newly designed spacecraft) should be free of black-zones with maximum *practical* abort options.
Quote from: AS-503 on 01/07/2014 11:35 pmQuote from: Robotbeat on 01/07/2014 11:29 pmQuote from: AS-503 on 01/07/2014 11:26 pmI thought a man-rated Delta IV was/is out of the question?Both with the current RS-68 and structural margins being below 1.4.Not out of the question. It's good enough for incredibly expensive and incredibly important national security assets (upon which millions of lives depend). We used to launch men on converted ICBMs, remember?While I agree with all of your points, sadly they are not relevant to NASA's standards for man-rated.Historically speaking Gemini pulled about 7gs on the way up (steep trajectory) on it's converted ICBM with "black zones" almost the entire way to orbit (even including sitting on the pad). Yes, I remember, but are you really arguing for a return to this type of (non) risk-aversion?After the two STS accidents, it is a safe assumption that all manned flights (on newly designed spacecraft) should be free of black-zones with maximum *practical* abort options.Delta IV doesn't have to have "black zones." It's a proven vehicle with a constant flight rate every year, thus I'd argue it is and will always be safer than any vehicle NASA would field.
I'm betting SpaceX 1Q 2016. To achieve this they will make it a priority over FH. This is what Dragon was designed for. It will give them a solid "first mover" advantage in the crew transportation market. And it will keep them visibly progressing towards their corporate Über-Goal.
I disagree FH is a bigger priority there are customers for FH, but other than NASA customers for a crewed Dragon are few and far between.
Quote from: sdsds on 01/09/2014 09:22 pmI'm betting SpaceX 1Q 2016. To achieve this they will make it a priority over FH. This is what Dragon was designed for. It will give them a solid "first mover" advantage in the crew transportation market. And it will keep them visibly progressing towards their corporate Über-Goal.I disagree FH is a bigger priority there are customers for FH, but other than NASA customers for a crewed Dragon are few and far between.
The in-flight abort test is the most challenging step in this process, i think. When they've got that done, there won't be a ton standing in their way but funding. And a pad, which will be lc39a. Basically everything else challenging (other than ECLSS) is analogous to Dragon cargo.We shall see how long it takes to build LC39A out to their purposes and ready to fly Dragon. It may take well into 2015 just for that part.
the schedule will be determined by CCtCap--not when SpaceX thinks they may be capable
Quote from: joek on 01/10/2014 04:16 amthe schedule will be determined by CCtCap--not when SpaceX thinks they may be capableBy that you're sort of saying that NASA might hold SpaceX back. Or am I reading too much into your comment?
NASA's end goal is to have a certified crew transport capability.
I see this less as NASA holding SpaceX back and more as providing adult supervision.
Quote from: joek on 01/10/2014 06:03 amNASA's end goal is to have a certified crew transport capability.NASA isn't homogeneous.
Congress wil continue it's trend of woefully underfunding commercial crew for the years to come. The impact will be (IMO) that none of the commercial crew providers that are currently in the contest (SN, Boeing and SpaceX) will make the 2017 deadline.
Quote from: sdsds on 01/10/2014 05:20 amQuote from: joek on 01/10/2014 04:16 amthe schedule will be determined by CCtCap--not when SpaceX thinks they may be capableBy that you're sort of saying that NASA might hold SpaceX back. Or am I reading too much into your comment?More that NASA may want to keep SpaceX from being overly aggressive, over-committing, and damaging themselves as well as the commercial crew program in the process. NASA's end goal is to have a certified crew transport capability. A crew test flight is obviously one point on that path, but achieving it at the earliest opportunity (as much as many people seem to focus on) is not necessarily required, desirable, or optimal. I see this less as NASA holding SpaceX back and more as providing adult supervision.
Quote from: woods170 on 01/10/2014 09:28 am Congress wil continue it's trend of woefully underfunding commercial crew for the years to come. The impact will be (IMO) that none of the commercial crew providers that are currently in the contest (SN, Boeing and SpaceX) will make the 2017 deadline.I think that while congress will do its "best" to achieve this, SpaceX is well funded enough to do it earlier anyway. Plus, they have other reasons to do it that just commercial crew. So I am hopeful to see it earlier, even if commercial crew itself will take longer.
SpaceX really does seem to have a certain drive to get things done, and not just for Commercial Crew.
The date of the milestones are provided by the company based on when they expect to accomplish them. If SpaceX wants to complete their program earlier than others they are free to propose earlier dates. But we'll find out what the real dates are when CCtCap is awarded. The 2015 date that SpaceX gave for the CCiCap optional milestones was based on an assumption that funding was not an issue. But we now know that funding is an issue. It will be interesting to see how much commercial crew gets in the soon to be released Appropriation bill for FY 2014.
Quote from: yg1968 on 01/10/2014 03:34 pmThe date of the milestones are provided by the company based on when they expect to accomplish them. If SpaceX wants to complete their program earlier than others they are free to propose earlier dates. But we'll find out what the real dates are when CCtCap is awarded. The 2015 date that SpaceX gave for the CCiCap optional milestones was based on an assumption that funding was not an issue. But we now know that funding is an issue. It will be interesting to see how much commercial crew gets in the soon to be released Appropriation bill for FY 2014. Agree that dates may be proposed, but NASA reserves the right to negotiate changes in content, pricing and schedule (that was the case for CCiCap, and is also the case for CCtCap). Also, while the CCtCap initial proposals are due Jan 22 2014, there are several steps, with "final proposal revisions" due June 2014. There will undoubtedly be quite a bit of negotiating until then.I also suggest SpaceX's optional milestone for a crewed test flight in 2015 was at best an aggressive token placeholder, and not something I would bet the farm on. The dates for CCiCap optional milestones in the original proposals are not a commitment; the actual date is negotiated at the time NASA selects an optional milestone for execution. Thus there was no risk to SpaceX being aggressive with dates for optional milestones in their original CCiCap proposal.As you say, funding is (and as importantly has been) an issue. In the best case SpaceX might conceivably have achieved a crewed test flight in 2015. Unfortunately the best case left the building long ago, with the inevitable slide to the right.
I agree with everything you said. That is a fair analysis. I also don't believe that NASA is trying to slow down SpaceX on purpose. The political and government process is slow but that is true for every company (not just SpaceX).
{snip}ECLSS and windows and manual controls and docking port will be needed in addition to the abort ability, but ECLSS is really the only somewhat complicated part, and I don't think it's /that/ challenging. Or expensive (compared to the in-flight abort).
In a vacuum chamber, of course. But under water-are you serious?
Quote from: Robotbeat on 01/11/2014 04:40 am{snip}ECLSS and windows and manual controls and docking port will be needed in addition to the abort ability, but ECLSS is really the only somewhat complicated part, and I don't think it's /that/ challenging. Or expensive (compared to the in-flight abort).A spacecraft with an ECLSS can be tested under water or in a vacuum chamber.
Quote from: A_M_Swallow on 01/11/2014 08:07 amQuote from: Robotbeat on 01/11/2014 04:40 am{snip}ECLSS and windows and manual controls and docking port will be needed in addition to the abort ability, but ECLSS is really the only somewhat complicated part, and I don't think it's /that/ challenging. Or expensive (compared to the in-flight abort).A spacecraft with an ECLSS can be tested under water or in a vacuum chamber.Capsule has positive pressure compared to vacuum, designed to not leak air out or explode (think of a balloon) in vacuum. Under water capsules ( eg sub) a designed not let water in or be crushed by external water pressure.