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I am wondering if there has been enough tests before the maiden manned flight of Demo-2 Crew Dragon. There were an autonomous flight test a year ago and a flight abort test late last year. There seem to be no other autonomous tests in between. Is this enough to give good confidence of the safety of the vehicle? What specific threshold requirements or conditions should be satisfied to obtain the approval for a maiden manned flight?

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    $\begingroup$ "crewed" not "manned" as per NASA policy... The Shuttle didn't have any flights without crew on board before STS-1 went to orbit and less abort modes so Crew Dragon may be safer even with just the 2 tests. $\endgroup$ – astrosnapper May 28 at 18:30
  • $\begingroup$ @astrosnapper Safe-"er" in this context is truly a relative term. $\endgroup$ – user3528438 May 29 at 18:37
  • $\begingroup$ A possible answer would be, how does it pass the relevant NASA/FAA requirements. $\endgroup$ – peterh - Reinstate Monica May 29 at 18:55
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    $\begingroup$ @Hans I think your question would have a chance to be reopened, if you would lawyerize it. Ask it, which requirements should it have passed. Then you get your reopen, your ups, and your answer(s). After that, you could ask (in another question), on what reasons are the requirements specified as ... enough? So you will it be okay, both of your question will be likely welcomed. $\endgroup$ – peterh - Reinstate Monica May 29 at 18:57
  • $\begingroup$ I think there are a few reasons why dragon uses less fight tests: 1) on the way up, the risk is more on the launch vehicle, which is already well proven, 2) The reenter vehicle is designed to be reusable,so on the first flight it's relatively "overbuilt" for the task, 3) Computers can simulate aerodynamics so there's less need for test fly the reentry. $\endgroup$ – user3528438 May 29 at 18:59
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  • The capsule itself did ground level abort test May 6, 2015.
  • They flew the capsule unmanned to orbit, docked to the ISS and reentered properly March 2, 2019.
  • They did an inflight abort Jan 19, 2020 where the capsule flew away from the booster midflight.
  • Technically this first two person flight will be a demo flight as well.

That is distinct tests of each stage of flight.

Sure they could test forever, but NASA with it's very rigorous standards (The joke is that the paper work for rating Dragon piles higher than the booster) signed off on it, and in fact did not require Boeing to even do a In Flight abort suggests that it was tested sufficiently.

Also it helps that the booster has 85 some odd flights on it, the Dragon capsule it is based upon has flown to the ISS 20+ and returned, demonstrate that in general they are capable of the task.

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  • $\begingroup$ By "the Dragon capsule it is based upon" do you mean the design of the Dragon capsule is largely/completely based upon some prior used capsule? $\endgroup$ – Hans May 29 at 18:06
  • $\begingroup$ SpaceX developed and launched the cargo Dragon, 23 (?) times so far. The heat shield experience, parachute experience, orbital RCS experience, water intrusion experience all directly carry over into Dragon Crew. This is the next upgrade to Dragon. Or perhaps you meant Dragon in general is based on something. I meant Dragon Crew (V2?) is based on Dragon Cargo (V1?). $\endgroup$ – geoffc May 31 at 2:00
  • $\begingroup$ Maybe it would be good if you incorporate the material in your last comment into your answer. $\endgroup$ – Hans May 31 at 4:22
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One thing to also keep in mind is that there are a whole host of tests that don't involve the flight of a vehicle. There are ground tests of the thrusters, hardware tests running flight software, testing the software in computer simulations, and all kinds of other tests. These tests demonstrate that the system is safe. The hardware tests verify that the software simulations work. While there might have only been a few flight tests, there is ample testing of the various systems, and NASA has reviewed all of this data and decided it is tested.

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    $\begingroup$ And Boeing's reasoning for not doing some of the physical tests that SpaceX did was that they would validate them via simulation. (To be fair, SpaceX offered to do the inflight abort, was not required by NASA). $\endgroup$ – geoffc May 28 at 20:27
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    $\begingroup$ There's a lot more to it. If you add in an extra safety factor, you don't have to test as carefully. Not being privy to either of those specific company's projects, I couldn't really tell you. $\endgroup$ – PearsonArtPhoto May 28 at 20:30

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