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Merged SpaceX’s Starship Rocket Explodes After Launch/Starship hop

And it 'landed' where they wanted it to.

I suspect that's as much success as they could hope for.

SN9 is just over there, they have a metric ****ton of data to apply to the next go.
 
Fare the well, SN8. You gave us good data, burning fairings, beautiful gimbaling recovering raptors, perfect belly flop, an incredible relight manouevre (2 out of 3 ain't bad) then an epic explosion. Mission absolutely accomplished.
 
Amazing flight and Elon Musk has tweeted that the problem was low pressure in the LOX header tank that lead to reduced thrust in the final stages, so I imagine a few tweaks will be made, the pad will be cleaned up and SN09 will move out, and any more extensive mods will go into SN10 and 11, got to love rapid prototyping. :)
 
Tweet from Elon Musk

"Successful ascent, switchover to header tanks & precise flap control to landing point!"

"Fuel header tank pressure was low during landing burn, causing touchdown velocity to be high & RUD, but we got all the data we needed! Congrats SpaceX team hell yeah!!"

I will be watching for Scott Manley's take on today's events
 
angrysoba said:
Chuck Yaeger would not have approved of the landing, but probably not too bad beyond that.

Could someone tell me what was going on with the engine that appeared loose? Was that by design or is that essentially the cause of the problem?

https://youtu.be/ap-BkkrRg-o?t=6601
Click to expand...

Here is the reason, as I understand it.

At this stage of development, the methalox powered Raptor engines can only be throttled down to 40% of maximum thrust, but the test was designed to take the rocket to a specific height, pitch it over and let it fall back to earth. Rather than throttle back the engines, they decided to shut down first one, then two then three engines to slow down and eventually stop the ascent

If you watch closely, at about T+1:40, the whole three engines gimbal to the bottom right of the picture just before the first engine (top left) gimbals outwards as it shuts down. This is done in order to reduce the sideways thrust as the two remaining running engines gimbal sharply to the centre to maintain the correct attitude. Same thing happens again at T+3:12 when the second engine shuts down. You can see that both the shut down engine nozzles are gimballed well away from centre to give the running engine a full range of movement.

You can see that all three nozzles have gimballed back to centre by the time the landing burn happened at T+6:30 with all three engines lighting
 
a_unique_person said:
So they try, first time, get this to land on the landing pad, right in the middle of the Boca Chita site. :boggled:
Click to expand...

Err, no! The launch pad is about two miles ENE of the main site where the control rooms and rocket build centre is

BocaChica.jpg
 
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smartcooky said:
Here is the reason, as I understand it.

At this stage of development, the methalox powered Raptor engines can only be throttled down to 40% of maximum thrust, but the test was designed to take the rocket to a specific height, pitch it over and let it fall back to earth. Rather than throttle back the engines, they decided to shut down first one, then two then three engines to slow down and eventually stop the ascent

If you watch closely, at about T+1:40, the whole three engines gimbal to the bottom right of the picture just before the first engine (top left) gimbals outwards as it shuts down. This is done in order to reduce the sideways thrust as the two remaining running engines gimbal sharply to the centre to maintain the correct attitude. Same thing happens again at T+3:12 when the second engine shuts down. You can see that both the shut down engine nozzles are gimballed well away from centre to give the running engine a full range of movement.

You can see that all three nozzles have gimballed back to centre by the time the landing burn happened at T+6:30 with all three engines lighting
Click to expand...

:thumbsup: Thanks for that!
 
Garrison said:
Amazing flight and Elon Musk has tweeted that the problem was low pressure in the LOX header tank that lead to reduced thrust in the final stages, so I imagine a few tweaks will be made, the pad will be cleaned up and SN09 will move out, and any more extensive mods will go into SN10 and 11, got to love rapid prototyping. :)
Click to expand...

Fuel header, not the LOX header.
The fuel also being the coolant for the engines and the thing that keeps the oxygen from eating them, which is why that last engine was so unhappy.
 
I thought the "bellyflop" thing was just so "meh!" - I mean they were just totally ripping off the "Adama maneuver from Battlestar Galactica:



(skip to 1:43 for the relevant part)
 
cjameshuff said:
Fuel header, not the LOX header.
The fuel also being the coolant for the engines and the thing that keeps the oxygen from eating them, which is why that last engine was so unhappy.
Click to expand...

My bad. Important thing is they were able to pin down the problem right away.
 
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