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This is the first time I've seen video of a starship test that didn't end in catastrophic explosion, so this is great news! I'm still worried about the overall

This is the first time I've seen video of a starship test that didn't end in catastrophic explosion, so this is great news! I'm still worried about the overall design, specifically when it comes to landing. The current procedure is for it to fall into the atmosphere flat on its side, then continue to fall for a long time, and then only when it's near the ground it must reorient 90 degrees to upright and then do a final suicide burn to land. It seems like it has too many chances to fail with no recovery, but I'm no rocket scientist.

bob33212 6y ago
It is a safer design because it is just 1 piece. There are a hundred ways it could fail. But that is within 1 system. Not multiple systems
imglorp 6y ago
To be fair, the hopper 150m test was ok. That was scaled down but retired risk for the raptor engine and fuel and controls. The full size is the same thing but with more structure and stress issues.
lmm 6y ago
Parachutes are a lot fiddlier and less reliable than the layperson assumes, so the baseline for how complex a system like this can be is worse than you'd think.
- doomlaser 6y ago
  In my mind, the multiple complex reorientations while falling at terminal velocity — with no plan B — just seems particularly harrowing..
  - Laremere 6y ago
    Doing it once is harrowing. Even doing it the tenth or the hundredth time might be harrowing. Doing it the thousandth time is starting to get old. Doing it the ten thousandth time is business as usual. The place to improve from is not as good as you may think, "On the Demo-2 mission, NASA has estimated a 1-in-276 chance of losing the crew at some point." Once you have full re-usability, you can fly rockets several orders of magnitude more times. When you're flying that often, you have the ability to work out the kinks. If instead you limit to what today feels the safest, you might limit yourself from full re-usability and eventually being much safer. If you want to still go for full re-usability, adding a backup system might actually make things more dangerous: It's another thing that has failure modes. Redundancy can be a double edged sword.
  - anticensor 6y ago
    Plan B is one more orbit and try again...
    - doomlaser 6y ago
      Once you've entered the atmosphere, you're falling to earth whether you like it or not. As it stands now, you must execute every move in the procedure or you crash into the ground at 120mph and explode.
avernon 6y ago
One thing to think about is that the heating/energy is exponential. So doing the belly flop lowers the heating and the energy the rocket is carrying quite a bit. Planes make 90 degree turns all the time! And in actuality this rocket could be less complex than a modern airliner as far as number of parts and processes. They have taken huge leaps in engine technology with Raptor that allow for a lot of simplification across the rest of the rocket and which could make it airliner level safe someday.
- rbanffy 6y ago
  It'll still be fun to hear the pilot announcing to the passengers that "We are now preparing for the suicide burn. Please make sure your seatbelts are fastened and your trays are securely stowed away. We wish you an enjoyable landing. Thank you for flying SpaceX".
jccooper 6y ago
Good news is, this is next on the test program. They'll be testing the "belly flop" with this vehicle in the next few flights. So they'll see any problems with it before they get too far. I don't see much reason to be worried about changing orientation in the long term. It's not in a particularly exotic flight regime (subsonic, lower atmosphere) and so long as the vehicle has sufficient control authority (and it will) anything that would cause that maneuver to fail would cause any other maneuver, like landing, to fail as well. The F9 actually already does a (less dramatic) version of this, and has never had a problem in that phase of flight.

bob33212 6y ago

It is a safer design because it is just 1 piece. There are a hundred ways it could fail. But that is within 1 system. Not multiple systems

imglorp 6y ago

To be fair, the hopper 150m test was ok. That was scaled down but retired risk for the raptor engine and fuel and controls. The full size is the same thing but with more structure and stress issues.

lmm 6y ago

Parachutes are a lot fiddlier and less reliable than the layperson assumes, so the baseline for how complex a system like this can be is worse than you'd think.

doomlaser 6y ago
In my mind, the multiple complex reorientations while falling at terminal velocity — with no plan B — just seems particularly harrowing..
- Laremere 6y ago
  Doing it once is harrowing. Even doing it the tenth or the hundredth time might be harrowing. Doing it the thousandth time is starting to get old. Doing it the ten thousandth time is business as usual. The place to improve from is not as good as you may think, "On the Demo-2 mission, NASA has estimated a 1-in-276 chance of losing the crew at some point." Once you have full re-usability, you can fly rockets several orders of magnitude more times. When you're flying that often, you have the ability to work out the kinks. If instead you limit to what today feels the safest, you might limit yourself from full re-usability and eventually being much safer. If you want to still go for full re-usability, adding a backup system might actually make things more dangerous: It's another thing that has failure modes. Redundancy can be a double edged sword.
- anticensor 6y ago
  Plan B is one more orbit and try again...
  - doomlaser 6y ago
    Once you've entered the atmosphere, you're falling to earth whether you like it or not. As it stands now, you must execute every move in the procedure or you crash into the ground at 120mph and explode.

avernon 6y ago

One thing to think about is that the heating/energy is exponential. So doing the belly flop lowers the heating and the energy the rocket is carrying quite a bit. Planes make 90 degree turns all the time! And in actuality this rocket could be less complex than a modern airliner as far as number of parts and processes. They have taken huge leaps in engine technology with Raptor that allow for a lot of simplification across the rest of the rocket and which could make it airliner level safe someday.

rbanffy 6y ago
It'll still be fun to hear the pilot announcing to the passengers that "We are now preparing for the suicide burn. Please make sure your seatbelts are fastened and your trays are securely stowed away. We wish you an enjoyable landing. Thank you for flying SpaceX".

jccooper 6y ago

Good news is, this is next on the test program. They'll be testing the "belly flop" with this vehicle in the next few flights. So they'll see any problems with it before they get too far. I don't see much reason to be worried about changing orientation in the long term. It's not in a particularly exotic flight regime (subsonic, lower atmosphere) and so long as the vehicle has sufficient control authority (and it will) anything that would cause that maneuver to fail would cause any other maneuver, like landing, to fail as well. The F9 actually already does a (less dramatic) version of this, and has never had a problem in that phase of flight.