The actual objective was to crash very slowly into the water, and to that end, I believe they planned for about 13 out of 33 to light for the "landing burn". But only about 5 lit up at that time, giving them a higher-speed crash-landing. However, the landing site was exactly where they needed to be, and done in complete safety, so that is good.
They had been explaining the post-ignition abort from last week, and showed how 4 out of 33 engines had failed to light on the first stage. This was due to some kind of pump malfunctions. They said that if 1 or 2 fail, it's OK to launch, but more than 2 is an automatic abort. So they were able to replace the finicky motors and fully test them out.
Who knows what caused the underthrust for the landing burn, but at least all 33 engines were operational at launch, and they got plenty of data from this test run, and all Starlink v3 satellites have been deployed successfully for their "suborbital speedrun", so this test flight is doing really awesome!
Damn so this probably means another identical suborbital flight in 6-8 weeks. It is looking less and less likely that we will see either prop transfer or a ship catch this year.
i don't think so - the ascent looked good. i don't think they need to put the ship on another suborbital trajectory because the booster landing burn failed. also, i don't think this impacts prop transfer or ship catch - both are separate problems.
Yup. Some of the Youtubers (like NASA Spaceflight) had video of it hitting the water pretty fast and hard. That said, this is the only test failure so far. I'm cautiously hopeful they get Ship to touch down. (it will explode after it does because of physics but stepping lightly onto the ocean will be a win)
And I sit corrected as it was able to lay down without rupturing the tanks and 'sploding. So that's another win.
What I find really amazing and cool is that while its reentering the engineering team can drive it around and look at heating effects on tiles/spars/etc all while retrieving telemetry by Starlink. What many people don't realize is that early capsules were the shape they were because that was the limit of what they could simulate for re-entry forces. The ability to get real time confirmation of systems response in re-entry is a capability that we've never had. So there's that.
So at this point it looks like they are down to un-reliabile raptor relights on the booster.
The size of ship being big enough to create a hole in the ionization to continue to communicate with Starlink is something that I think gets underappreciated.
Is this just a fancy way of saying lightweight fragile aerospace tube with hot stuff all over the outside and flammable stuff on the inside will not respond well to falling on it's side or is there some other thing going on here I don't know about.
Sort of? Everything is weight. And since it isn't a design feature to lay down in water there isn't any weight budget for making that modality survivable? So typically when it falls (and this thing is really tall) the interior tanks detach from their mounts and hit the inside walls and rupture. The skin is still hot, oxygen and remaining fuel mix and it goes boom. This time we had fires but no boom. I look forward to hearing what was different.
No, that's exactly what happens. Most of the time.
There was a couple of times when SpaceX accidentally soft landed a Falcon 9 first stage into the ocean, and had it just float around. They're yet to do that trick with Starship though.
I am pretty unconvinced that any of the past explosions of starship used that feature. It’s very convenient to have an “explode” button so you can say all of your rocket detonations were intentional, but they are often leaking fuel or dropping chunks before they explode.
from what i understand it kind of is a failure. It's suppose to tip over, explode, and sink. That way you don't have all this ITAR regulated tech floating around in international waters.
Yes, because it would have landed a few hundred meters out from the chopsticks. It swings in towards the catcher as part of its slowdown. If it doesn't slow down, that doesn't happen.
By the time that the booster returns to the landing zone, the Flight Termination System (FTS) is AFAIK no longer active and cannot be reactivated. Which makes sense because it is a bunch of high explosives, now nearing some valuable equipment.
The SpaceX solution is to steer carefully and have the default trajectory end in the sea. Only if everything looks good, is the booster redirected to the tower.
The actual objective was to crash very slowly into the water, and to that end, I believe they planned for about 13 out of 33 to light for the "landing burn". But only about 5 lit up at that time, giving them a higher-speed crash-landing. However, the landing site was exactly where they needed to be, and done in complete safety, so that is good.
They had been explaining the post-ignition abort from last week, and showed how 4 out of 33 engines had failed to light on the first stage. This was due to some kind of pump malfunctions. They said that if 1 or 2 fail, it's OK to launch, but more than 2 is an automatic abort. So they were able to replace the finicky motors and fully test them out.
Who knows what caused the underthrust for the landing burn, but at least all 33 engines were operational at launch, and they got plenty of data from this test run, and all Starlink v3 satellites have been deployed successfully for their "suborbital speedrun", so this test flight is doing really awesome!
Damn so this probably means another identical suborbital flight in 6-8 weeks. It is looking less and less likely that we will see either prop transfer or a ship catch this year.
i don't think so - the ascent looked good. i don't think they need to put the ship on another suborbital trajectory because the booster landing burn failed. also, i don't think this impacts prop transfer or ship catch - both are separate problems.
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They don’t have to catch the booster to test any of that.
Yup. Some of the Youtubers (like NASA Spaceflight) had video of it hitting the water pretty fast and hard. That said, this is the only test failure so far. I'm cautiously hopeful they get Ship to touch down. (it will explode after it does because of physics but stepping lightly onto the ocean will be a win)
And I sit corrected as it was able to lay down without rupturing the tanks and 'sploding. So that's another win.
What I find really amazing and cool is that while its reentering the engineering team can drive it around and look at heating effects on tiles/spars/etc all while retrieving telemetry by Starlink. What many people don't realize is that early capsules were the shape they were because that was the limit of what they could simulate for re-entry forces. The ability to get real time confirmation of systems response in re-entry is a capability that we've never had. So there's that.
So at this point it looks like they are down to un-reliabile raptor relights on the booster.
Congrats to everyone who worked on this.
The size of ship being big enough to create a hole in the ionization to continue to communicate with Starlink is something that I think gets underappreciated.
>it will explode after it does because of physics
Is this just a fancy way of saying lightweight fragile aerospace tube with hot stuff all over the outside and flammable stuff on the inside will not respond well to falling on it's side or is there some other thing going on here I don't know about.
Sort of? Everything is weight. And since it isn't a design feature to lay down in water there isn't any weight budget for making that modality survivable? So typically when it falls (and this thing is really tall) the interior tanks detach from their mounts and hit the inside walls and rupture. The skin is still hot, oxygen and remaining fuel mix and it goes boom. This time we had fires but no boom. I look forward to hearing what was different.
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No, that's exactly what happens. Most of the time.
There was a couple of times when SpaceX accidentally soft landed a Falcon 9 first stage into the ocean, and had it just float around. They're yet to do that trick with Starship though.
EDIT: Of fucking course.
How many times have they managed to catch it in the last 8 or so missions? There have been a few misses like this already with the boosters
They only tried to catch it twice, and they caught it twice.
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I guess they also failed to explode it
I am pretty unconvinced that any of the past explosions of starship used that feature. It’s very convenient to have an “explode” button so you can say all of your rocket detonations were intentional, but they are often leaking fuel or dropping chunks before they explode.
This was a great flight, though.
from what i understand it kind of is a failure. It's suppose to tip over, explode, and sink. That way you don't have all this ITAR regulated tech floating around in international waters.
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Re-light seems to be one of their biggest remaining obstacles in a lot of these flight tests.
It was going in the water anyway, but yeah, it touched visibly faster than it should have.
The “chopstick” catcher arrangement seems awfully fragile. Would the ground equipment have survived this if it had been a real catch?
Yes, because it would have landed a few hundred meters out from the chopsticks. It swings in towards the catcher as part of its slowdown. If it doesn't slow down, that doesn't happen.
They generally initiate landing aiming just off shore and only adjust to the landing pad after everything is nominal. So yes.
Rockets have a self destruct feature to avoid exactly this type of contingency
By the time that the booster returns to the landing zone, the Flight Termination System (FTS) is AFAIK no longer active and cannot be reactivated. Which makes sense because it is a bunch of high explosives, now nearing some valuable equipment.
The SpaceX solution is to steer carefully and have the default trajectory end in the sea. Only if everything looks good, is the booster redirected to the tower.
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