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Starship's Third Flight Test [video]

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Re: Starship's Third Flight Test [video]

#311

Post by mgiampapa »

avmich wrote: post #305
mgiampapa wrote: post #288

Earlier quoted context omitted.

Passenger rating isn't even in the cards for Starship for a long time. You ride to LEO on a Falcon-9 with a proven track record for the foreseeable future.

"Foreseeable" is roughly "five years"? Starship HLS (Human Landing System) is currently planned to land on the Moon, with people, in 2026. It may very well slip a year, two or three - but landing on the Moon this decade still seems quite possible. Or you consider "passengers" different enough than "crew"?

Yes, landing on the Moon without an atmosphere is vastly different from orbital flight on earth and has an entirely different risk profile.

Re: Starship's Third Flight Test [video]

#312

Post by johnyzee »

aeternum wrote: post #300
johnyzee wrote: post #138

Earlier quoted context omitted.

Yeah, breaking up in-air during re-entry (at 65 km going by last telemetry) seems like a potential big issue to fix.

Why? Saturn V broke up in-air during re-entry on every "successful" launch as does every ULA rocket.

Because that is their stated design goal for Starship.

Re: Starship's Third Flight Test [video]

#313

Post by DarmokJalad1701 »

bdamm wrote: post #299
DarmokJalad1701 wrote: post #267

Earlier quoted context omitted.

> This was still a suborbital flight and they cannot do much of anything that is commercially practical on suborbital flights If they had flown a slightly steeper ascent and burned for a little longer (possibly a minute if not less), they would have ended in a stable orbit. Not doing that was intentional. They do not need engine relight capability to reach orbit - plenty of orbital rockets exist that cannot relight t…

Yes, but the point was that they can't launch starlinks or just about any commercially meaningful payload until they are reliably in orbit, and they can't reliably get into orbit until they demonstrate at least one relight, because they need to reliably re-enter the atmosphere for the reusability tests. So they are at least one more launch away from launching starlinks.

> commercially meaningful payload until they are reliably in orbit,

Which then can do without a relight.

> and they can't reliably get into orbit until they demonstrate at least one re-light

And part of testing deorbit/landing capability includes testing that they can relight the engine.

So they could launch the next one with Starlinks (possibly test articles of those as well since no full-size V2 satellites have been laucnhed yet). Get it into orbit and include a deorbit burn/re-entry as part of the flight plan. If the latter part somehow still does not work out ... they still got Starlinks into orbit. And they now have more data to fix it on the next flight. They already have several vehicles lined up for static fires and flight tests.

Re: Starship's Third Flight Test [video]

#314

Post by smallmancontrov »

usrusr wrote: post #301
dotnet00 wrote: post #157

Earlier quoted context omitted.

OP's point is that the tests become a bit cheaper and a bit easier to get licenses for since they can get to orbit and can deploy Starlinks. The reentry problems of course have to be fixed, but the FAA mishap investigation will involve fewer delays, just like how Falcon 9 was able to keep flying, attempting landings without having to wait for a mishap investigation to finish every time a landing failed.

Iirc F9 had its main challenge in that final suicide burn. Usually the boosters made it there just fine and then "only" failed to get the parameters aligned just right. Based on what we saw today, the main chokepoint for Starship might be right in that hot reentry telemetry blind spot. Debugging without logs.

With all the solid state gizmos we have today, is it really that difficult to make a blackbox that can survive serious impact G-forces, especially if it just needs to work and doesn't need to be safety rated?

Re: Starship's Third Flight Test [video]

#315

Post by K0balt »

tempaway444641 wrote: post #175
pixl97 wrote: post #116

Earlier quoted context omitted.

>T+46: the little bits of debris must be tiles coming off Seemed like ice to me, which itself can be it a problem. The vehicle didn't seem very stable even before this point so I'm wondering if we're getting ice build up on the cold gas thrusters which changed the control dynamics keeping the ship from flying stably.

Yeah could be. Some of the debris looked very specific in shape though. On some shots of starship you can see missing tiles (not many though)

It looked to me like a good portion of the debris was in fact tiles. It also seemed to me that there were significant attitude control deviations, both of which might have been significant factors in the unplanned disassembly event.

Re: Starship's Third Flight Test [video]

#316

Post by DarmokJalad1701 »

usrusr wrote: post #301
dotnet00 wrote: post #157

Earlier quoted context omitted.

OP's point is that the tests become a bit cheaper and a bit easier to get licenses for since they can get to orbit and can deploy Starlinks. The reentry problems of course have to be fixed, but the FAA mishap investigation will involve fewer delays, just like how Falcon 9 was able to keep flying, attempting landings without having to wait for a mishap investigation to finish every time a landing failed.

Iirc F9 had its main challenge in that final suicide burn. Usually the boosters made it there just fine and then "only" failed to get the parameters aligned just right. Based on what we saw today, the main chokepoint for Starship might be right in that hot reentry telemetry blind spot. Debugging without logs.

Unlike with F9, in this case they most probably had high-bandwidth telemetry all the way till the vehicle broke up (if the high-def video stream is anything to go by). So, they probably have a lot more data this time. Even the video can yield information - for example, given that the cameras were mounted on the flaps, they can probably back out the actuation angles from that.

Re: Starship's Third Flight Test [video]

#317

Post by DarmokJalad1701 »

johnyzee wrote: post #312
aeternum wrote: post #300

Earlier quoted context omitted.

Why? Saturn V broke up in-air during re-entry on every "successful" launch as does every ULA rocket.

Because that is their stated design goal for Starship.

And you don't need to meet that goal to start launching (risk-tolerant) payloads to orbit during their test flights. Especially with such a hardware-rich development program.

Re: Starship's Third Flight Test [video]

#318

Post by kristianp »

DarmokJalad1701 wrote: post #80

The test is essentially a success at this point. Starship can take payload to orbit and open/close the payload doors. The remaining things are icing on the cake. They can refine re-usability while flying payloads.

Maybe the words "success" and "failure" are too difficult to shoehorn into describing these tests, especially with the first two tests.

"Great progress" is a good intermediate.

Re: Starship's Third Flight Test [video]

#319

Post by birdman3131 »

93po wrote: post #293
bane wrote: post #280

Earlier quoted context omitted.

Now do the same calculation in units of hubble space telescope and james webb space telescope masses. Then look at expected reusable launch cost and figure out how many HSTs or JWSTs we could have put in orbit for the same cost.

JWST would also be incredibly less expensive if it didn't have to do the very complex folding required by smaller rockets

How much larger could we have made it still doing the folding on starship?
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