35
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So with Soyuz being retired, what gets people up to the ISS and back down now?
Soyuz the booster and Soyuz the person carrying spacecraft are different.
Soyuz the booster is based on the original R-7 ICBM and has seen a series of upgrades. Sometimes to engines, sometimes to ...
- 80.2k
19
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Why was the Saturn V considered to be human-rated after Apollo 6?
The Apollo project was driven by Kennedy's "end of the decade" timeline; time was of the essence. Both time and budget pressure forced the program to take risks that they might not have in an ideal ...
- 170k
18
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What standard was used by NASA to certify the Dragon capsule controls as safe for crewed flight?
As I am not privy to the contractual interactions between NASA and SpaceX, I cannot say with an absolute certainty that NASA and SpaceX had astronauts, pilots, etc. evaluate the vehicle beforehand ...
- 75.5k
11
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What are the most difficult challenges SpaceX will face getting astronauts to Mars by about 2025?
Since there have been no answers in over a week, I'll venture a partial answer.
There are of course several challenges. Among them in no particular order:
Crew selection and training
Putting together,...
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8
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Why doesn't carbon fiber overwrapping in LOX catch fire? (watch this video first)
Liquid oxygen mixed with carbon powder has been used as an explosive for mining, see 1, 2. But there has been an explosion in a helium purifier 3.
The use for mining required safe explosives, the rate ...
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7
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Are second stage RUDs less common than first stage ones?
Many entries in this 1957-2015 Catalogue of Launch Vehicle Failures mention stage numbers. By my tally, the blame for launch failure goes to the first stage 42 times; the second, 60; the third, 36.
...
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6
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How can SLS be ready to carry humans after just a single test flight?
tl;dr The development processes of SLS vs. New Shepard and specifically Falcon 9 are vastly different.
I don't understand how this is possible. How can a hyper-complex rocket, that has literally ...
- 20k
6
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Should SpaceX have 2 versions of the Falcon 9 rocket (cargo-only and human-only)?
In a sense SpaceX did just that: they started with a cargo-only rocket and gradually improved it with their two goals of reusability and human-rating in mind. This plan meant the rocket was already ...
- 128k
6
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Human-rating the Saturn V using modern standards
Most showstoppers come from the fact that the Saturn/Apollo programs are not active, and have not been for a long time.
Human rating primarily applies to the design process. The Saturn/Apollo were ...
5
votes
How many companies are working on creating viable spaceplanes in the near future for human spaceflight(10-20 years)
At this point the only company actively working (at least publicly) on creating a "spaceplane" for human spaceflight is Virgin Galactic (Plane actually made by Scaled Composites). Their SpaceshipTwo ...
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So with Soyuz being retired, what gets people up to the ISS and back down now?
Soyuz capsule and Progress cargo ship will be launched over Soyuz FG and Soyuz 2.1a boosters - they all from the same R-7 boosters family
Soyuz FG has minor changes of mixing heads comparable to the ...
- 3,024
5
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Why are the very reliable rockets Atlas V and Ariane V not rated for human flight?
For Ariane 5, the reason is simple that ESA don't have a sovereign manned program.
The rocket was initially planned to be human rated.
It has been be quoted as one of the reason why the rocket is ...
- 12.7k
4
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What are the most difficult challenges SpaceX will face getting astronauts to Mars by about 2025?
While Mike's answer is very well researched and written. I disagree with its challenges (though I don't disagree with his conclusions).
The biggest challenges that SpaceX will need to solve in my ...
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4
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How are SLS SRBs considered man-rated?
Human certification has little to do with a concept and more to do with the Factor of Safety in mission-critical design aspects. SRBs are very reliable and predictable in ignition and burn (if you ...
- 801
4
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Has Falcon 9 block 5's design stopped evolving?
While there may not be any direct evidence to cite, one can infer from some of the available information.
The first Block 5 booster, was basically B1046. (Which flew 4 times, and was lost on purpose ...
- 80.2k
4
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What standard was used by NASA to certify the Dragon capsule controls as safe for crewed flight?
Sorry, I can't truly answer the main question, as I don't have access to that information. This is more of a general answer to OP's statement:
you can't reliably tell whether your input has been ...
4
votes
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What launch vehicles of those compatible will Starliner actually use?
When this kind of compatibility is required, they mostly mean mechanically, vibrations and things like that. The software isn't written, nor the conops, and other tests haven't likely been done. In ...
- 122k
4
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Which CI/CD system do/would space companies like SpaceX use for continuous integration in their devops practice?
The question assumes there is a concept of "Continuous Delivery" in space flight software. There is not. The required product assurance processes do not allow it.
I'll consider ECSS standards here, ...
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3
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Which CI/CD system do/would space companies like SpaceX use for continuous integration in their devops practice?
You are using web site development terms. While some of those concepts do indeed apply to the development flight software, some do not, and some are so far off as to make "completely off base&...
- 75.5k
2
votes
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What are some details of ISRO's Gaganyaan Mission?
The Indian Human Space Flight Programme "Gaganyaan" (Sanskrit: गगनयान, "Sky Vehicle")
Number of Crew member:
Gaganyaan is a fully autonomous 3.7-tonne (8,200 lb) spacecraft designed to carry a 3-...
2
votes
Human Rate the ICPS on EM-1 of SLS
Compliance is mandatory!
Human Rating Requirements for Space Systems
It's long, even with the rationale scraped out, but here you go.
3.2 System Safety Requirements
3.2.1 The space system shall ...
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2
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What is the point of launching EM-1 on DIVH/F9H?
what of the original purpose of EM-1 would be served...?
It is hard to tell from the NASA administrator's comments in Ars Technica's Here’s why NASA’s administrator made such a bold move Wednesday:
&...
- 149k
2
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Are second stage RUDs less common than first stage ones?
The first stage filters out a lot of the mistakes.
Pretty much the entire stack is tested to some extent during the first stage. This includes the hardware being subject to vibration and force as ...
- 3,442
1
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What is the point of launching EM-1 on DIVH/F9H?
Sadly, the point may just be to kick the SLS folks in the butt to be on time and on budget for once, that Senate support of their laziness may be blocked by the administration. Doing the LEO assembly ...
- 723
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So with Soyuz being retired, what gets people up to the ISS and back down now?
I believe the Dragon 2 may have a 2017 launch date. Orion is on track for a 2018 launch, and NASA is investigating whether to make the unmanned launch for 2017 a manned launch as well.
Only top scored, non community-wiki answers of a minimum length are eligible