4 ms·

Second stage lost, looks like the flight termination system did its job. Unknown as to why yet. Going to be very very interesting to see the data that's release

Second stage lost, looks like the flight termination system did its job. Unknown as to why yet. Going to be very very interesting to see the data that's released from this as well as all the higher quality video/stills that surface.

Podgajski 3y ago
[flagged]
- dotnet00 3y ago
  It's just because last time that was an issue.
  - badcppdev 3y ago
    100% and that issue was very important to the FAA. Being able to blow up a rocket if it starts to go off course is absolutely critical
- olig15 3y ago
  Im not interpreting their message as negative. Something obviously went wrong, the termination system was activated, and it blew up. Thats what it’s supposed to do when activated.
  - Thorrez 3y ago
    >Im not interpreting their message as negative. But shouldn't it be interpreted as negative? It blew up.
    - mcpackieh 3y ago
      The FTS failed last time and it caused months of delays with the FAA. This time it worked so there should be fewer delays from regulators in the future.
    - spdif899 3y ago
      It's not the most ideal possible outcome, but overall the launch was a pretty huge success for SpaceX (and for space fans by extension). The fact they made it so much further than the first launch, seemingly having corrected all the notable things that went wrong there, is very good news - the flight test process serves to root out unknowns and today's launch shows they've done so (and now found some more to work on for the next launch). So to answer your question, I don't think it should really be interpreted as a negative, as the primary goals were met and the controlled nature of the launch seems promising for SpaceX getting cleared to keep trying.
    - TeMPOraL 3y ago
      You learn more from mission failure than success, so failures are useful in the testing stage.
    - __MatrixMan__ 3y ago
      ...and blowing things up, when nobody gets hurt, is a lot of fun.
    - midasuni 3y ago
      If your program crashes while you are developing it, is that a failure?
    - ben_w 3y ago
      Which is worse: having to send SIGKILL, or a OS bug causing your app to perform potentially dangerous undefined behaviour for 30 seconds after being sent SIGKILL? First launch had something analogous to latter, this launch had two counts analogous to the former.
- prepend 3y ago
  What’s summoning positions?
- ReptileMan 3y ago
  In space you want the things to blow hard and early. No one wants Boing 737 Max lurking in the vehicle. They fixed previous mistakes and made new ones. Eventually if they don't repeat the same ones they will run out of big mistakes and it will be smooth sailing afterwards.
- mcpackieh 3y ago
  The FTS actually working this time is positive. FTS exists for a good reason, it working is therefore good.
- deleted 3y ago
  [deleted]
- stetrain 3y ago
  The FTS taking too long to destroy the rocket was one of the issues with the first flight and the subject of an FAA review and mitigations for this flight. Safety is always more important than getting your rocket to orbit.
- ericcumbee 3y ago
  Considering that the FTS system didn't really do its job on IFT-1. it detonated but it took a while for the stack to lose enough pressurization and structural rigidity to break up. This time it did exactly what it was supposed to do.
testplzignore 3y ago
Good trivia question: Is this the first rocket launch to have two separate RUDs?
- dotnet00 3y ago
  Do second stage failures on other rockets, where the booster is a guaranteed rapidly-scheduled-destruction count? :P
  - sebzim4500 3y ago
    No because that wouldn't be unscheduled.
jccooper 3y ago
AFTS activation indicates deviation from planned trajectory. It's unusual, being so late in the burn. Could be a guidance issue, but SpaceX should be pretty good at that by now. Could be engine underperformance, but we got nominal callouts and it would have to be pretty bad for AFTS to notice with minutes left, so that seems unlikely. I'd guess engine control (due to damage during staging) is the main suspect. We say the thrusters fighting pretty hard there at the end, which supports that idea.
- goku12 3y ago
  I wonder if something happened at around T+7:39. There is a rather sudden and large plume when the starship should've been in steady state.
- lutorm 3y ago
  I dunno, it looks like a nominal shutdown to me. The speed readout shows rapidly decreasing acceleration just as the engine displays go out instead of the telemetry suddenly going stale as you'd expect if it just blew up during the burn. Then, after the acceleration has gone to zero, the telemetry goes stale, so my guess would be on something going wrong during shutdown (ullage collapse when the propellant sloshes forward as the engines shut down maybe, this was a problem during the first landing test.) AFTS seems unlikely this late in the burn, I think they said it was in terminal guidance and it's very hard to laterally change the impact point in any meaningful way with that much velocity. But I agree, it definitely looked like something's venting near the end, too.
  - jltsiren 3y ago
    Starship engines were cut off at 8:03, while the nominal mission profile in Wikimedia mentions SECO at 8:33. The speed at cutoff was ~24000 km/h at an altitude of ~150 km. Without the AFTS, the Starship would have crashed somewhere in the Atlantic.
    - lutorm 3y ago
      Yes, good point, the velocity was too low. Yet it looked like all the engines just shut down nominally.
Geojim 3y ago
Isn't an exploding rocket in space a bad thing - ie debris everywhere? I know space is big but aren't there now a few thousand more pieces of space junk to track. I suppose they're worried about a starship landing on someone's home - but still seems a tad premature.
- ethangk 3y ago
  It's more of an issue when the thing exploding is in orbit. This was a (just) suborbital launch, and I think the first stage was quite a bit slower/ lower than orbital at the point that it exploded, meaning it'll all just fall to Earth
- kobalsky 3y ago
  it was not in orbit yet so I think everything should fall back down to earth.
- invalidator 3y ago
  As long as it hasn't achieved orbit, all the pieces will end up on an elliptical track with the lowest point inside the atmosphere. Some stuff might get flung way up, but it would still need another maneuver (requiring working engines) near the highest point to circularize the track to prevent it from coming back down. There's not much ambiguity for when to destruct. It's just: has it gone far enough off course that it could free-fall outside the predetermined borders where it's acceptable to crash? Then it's time to blow it up so it doesn't fly any farther.

Podgajski 3y ago

[flagged]

dotnet00 3y ago
It's just because last time that was an issue.
- badcppdev 3y ago
  100% and that issue was very important to the FAA. Being able to blow up a rocket if it starts to go off course is absolutely critical
olig15 3y ago
Im not interpreting their message as negative. Something obviously went wrong, the termination system was activated, and it blew up. Thats what it’s supposed to do when activated.
- Thorrez 3y ago
  >Im not interpreting their message as negative. But shouldn't it be interpreted as negative? It blew up.
  - mcpackieh 3y ago
    The FTS failed last time and it caused months of delays with the FAA. This time it worked so there should be fewer delays from regulators in the future.
  - spdif899 3y ago
    It's not the most ideal possible outcome, but overall the launch was a pretty huge success for SpaceX (and for space fans by extension). The fact they made it so much further than the first launch, seemingly having corrected all the notable things that went wrong there, is very good news - the flight test process serves to root out unknowns and today's launch shows they've done so (and now found some more to work on for the next launch). So to answer your question, I don't think it should really be interpreted as a negative, as the primary goals were met and the controlled nature of the launch seems promising for SpaceX getting cleared to keep trying.
  - TeMPOraL 3y ago
    You learn more from mission failure than success, so failures are useful in the testing stage.
  - __MatrixMan__ 3y ago
    ...and blowing things up, when nobody gets hurt, is a lot of fun.
  - midasuni 3y ago
    If your program crashes while you are developing it, is that a failure?
  - ben_w 3y ago
    Which is worse: having to send SIGKILL, or a OS bug causing your app to perform potentially dangerous undefined behaviour for 30 seconds after being sent SIGKILL? First launch had something analogous to latter, this launch had two counts analogous to the former.
prepend 3y ago
What’s summoning positions?
ReptileMan 3y ago
In space you want the things to blow hard and early. No one wants Boing 737 Max lurking in the vehicle. They fixed previous mistakes and made new ones. Eventually if they don't repeat the same ones they will run out of big mistakes and it will be smooth sailing afterwards.
mcpackieh 3y ago
The FTS actually working this time is positive. FTS exists for a good reason, it working is therefore good.
deleted 3y ago
[deleted]
stetrain 3y ago
The FTS taking too long to destroy the rocket was one of the issues with the first flight and the subject of an FAA review and mitigations for this flight. Safety is always more important than getting your rocket to orbit.
ericcumbee 3y ago
Considering that the FTS system didn't really do its job on IFT-1. it detonated but it took a while for the stack to lose enough pressurization and structural rigidity to break up. This time it did exactly what it was supposed to do.

testplzignore 3y ago

Good trivia question: Is this the first rocket launch to have two separate RUDs?

dotnet00 3y ago
Do second stage failures on other rockets, where the booster is a guaranteed rapidly-scheduled-destruction count? :P
- sebzim4500 3y ago
  No because that wouldn't be unscheduled.

jccooper 3y ago

AFTS activation indicates deviation from planned trajectory. It's unusual, being so late in the burn. Could be a guidance issue, but SpaceX should be pretty good at that by now. Could be engine underperformance, but we got nominal callouts and it would have to be pretty bad for AFTS to notice with minutes left, so that seems unlikely. I'd guess engine control (due to damage during staging) is the main suspect. We say the thrusters fighting pretty hard there at the end, which supports that idea.

goku12 3y ago
I wonder if something happened at around T+7:39. There is a rather sudden and large plume when the starship should've been in steady state.
lutorm 3y ago
I dunno, it looks like a nominal shutdown to me. The speed readout shows rapidly decreasing acceleration just as the engine displays go out instead of the telemetry suddenly going stale as you'd expect if it just blew up during the burn. Then, after the acceleration has gone to zero, the telemetry goes stale, so my guess would be on something going wrong during shutdown (ullage collapse when the propellant sloshes forward as the engines shut down maybe, this was a problem during the first landing test.) AFTS seems unlikely this late in the burn, I think they said it was in terminal guidance and it's very hard to laterally change the impact point in any meaningful way with that much velocity. But I agree, it definitely looked like something's venting near the end, too.
- jltsiren 3y ago
  Starship engines were cut off at 8:03, while the nominal mission profile in Wikimedia mentions SECO at 8:33. The speed at cutoff was ~24000 km/h at an altitude of ~150 km. Without the AFTS, the Starship would have crashed somewhere in the Atlantic.
  - lutorm 3y ago
    Yes, good point, the velocity was too low. Yet it looked like all the engines just shut down nominally.

Geojim 3y ago

Isn't an exploding rocket in space a bad thing - ie debris everywhere? I know space is big but aren't there now a few thousand more pieces of space junk to track. I suppose they're worried about a starship landing on someone's home - but still seems a tad premature.

ethangk 3y ago
It's more of an issue when the thing exploding is in orbit. This was a (just) suborbital launch, and I think the first stage was quite a bit slower/ lower than orbital at the point that it exploded, meaning it'll all just fall to Earth
kobalsky 3y ago
it was not in orbit yet so I think everything should fall back down to earth.
invalidator 3y ago
As long as it hasn't achieved orbit, all the pieces will end up on an elliptical track with the lowest point inside the atmosphere. Some stuff might get flung way up, but it would still need another maneuver (requiring working engines) near the highest point to circularize the track to prevent it from coming back down. There's not much ambiguity for when to destruct. It's just: has it gone far enough off course that it could free-fall outside the predetermined borders where it's acceptable to crash? Then it's time to blow it up so it doesn't fly any farther.