Wiki Super Heavy/Starship - General Development Discussion

[HVM]

"RAPTORS!!!! I REPEAT! RAPTORS FOR SN8!!!"
https://twitter.com/MatthewCable6/status/1315289132046974976

"Raptor Serial Number 29
This full-flowstage combustion cycle engine, will propel StarShip SN6 into the Boca Chica skies during upcoming hop tests."

https://twitter.com/austinbarnard45/status/1295753726628712448?s=19

 

[ICUDoc]

Looks like a birds nest on a kid’s sand bucket...

 

[HVM]

It’s Time to Visit Our Eye Clinic

 

[ICUDoc]

Beautiful madness

 

[EVCollies]

The First Belly Flop Landings
Just thinking as I'm typing, but the animation of this landing shows so much happening in the last few seconds. Seems like a lot could go wrong and wipe out a lot of equipment at Boca Chica. I'm wondering how they will test these safely?

I recall with the Falcon 9 that landed in the water 2 years ago that the landings are initially planned for a water landing but moved to the landing zone if all is well.

Could they accomplish a similar safety measure with a Starship belly flop? Or would they just land a few in the water, sacrificing the ship and engines?

 

[mongo]

The First Belly Flop Landings
Just thinking as I'm typing, but the animation of this landing shows so much happening in the last few seconds. Seems like a lot could go wrong and wipe out a lot of equipment at Boca Chica. I'm wondering how they will test these safely?

I recall with the Falcon 9 that landed in the water 2 years ago that the landings are initially planned for a water landing but moved to the landing zone if all is well.

Could they accomplish a similar safety measure with a Starship belly flop? Or would they just land a few in the water, sacrificing the ship and engines?

No need to do the first attempt near ground level. They can rotate much higher and then land like an F9. Or possibly, go back up for another test.

Final run of the mission can be off shore and hover back to the landing site.

 

[EVCollies]

No need to do the first attempt near ground level. They can rotate much higher and then land like an F9. Or possibly, go back up for another test.

Final run of the mission can be off shore and hover back to the landing site.

Great to hear, I had learned the Falcon 9 was not able to hover like the New Shepard does before landing given the engine limitations. This would give Starship and added measure of safety.

 

[miimura]

Great to hear, I had learned the Falcon 9 was not able to hover like the New Shepard does before landing given the engine limitations. This would give Starship and added measure of safety.

My impression is that Falcon 9 landing attempts were all done after delivering a real payload to orbit. Under those conditions, it's hard to have enough fuel left to play around with hovering. All the early Starship tests will be the primary objective, not a secondary objective after delivering payloads to orbit.

 

[mongo]

My impression is that Falcon 9 landing attempts were all done after delivering a real payload to orbit. Under those conditions, it's hard to have enough fuel left to play around with hovering. All the early Starship tests will be the primary objective, not a secondary objective after delivering payloads to orbit.

A single Merlin engine at minimum output still puts out more thrust than the weight of a F9 first stage when near empty (landing). There is no ability to hover due to this and the computer needs to get velocity to zero at the same monent that altitude (relative to barge) is zero. If too soon, it starts climbing again. One of the earlier landings was extra hard because it stopped a bit above the deck, then dropped.

The thrust to weight ratio of a low fuel Starship second stage is much less than an F9 booster. Even if still greater that one at min throttle on a single engine, they can practice at altitude by setting an arbitrary height as the ground level.

Whether they will or not is yet to be seen.

 

[HVM]

 

[ICUDoc]

View attachment 598353

Do you have those backwards?

 

[Grendal]

Fuel depots in space:

SpaceX tweet: NASA has selected Starship for a propellant transfer demonstration! Combining Starship’s rapid reusability with orbital refilling is critical to economically transporting large numbers of crew and cargo to the Moon and Mars.

https://twitter.com/spacex/status/1...vEtz5XCT8tNvZnk-30g3txGvDI8hgpVXLO8kJWzstd_Zs

 

[bxr140]

Do you have those backwards?

Do you need the joke explained?

 

[e-FTW]

Something's going down (usually up, and then down...) tonight: https://twitter.com/BocaChicaGal/status/1316432298569498624?s=20

 

[favo]

Something's going down (usually up, and then down...) tonight:

Looks to be a static fire of the three raptors installed on the SN8 Starship prototype.

 

[e-FTW]

Looks to be a static fire of the three raptors installed on the SN8 Starship prototype.

That is my understanding as well. I want to hear that!

 

[Buckminster]

Just thinking about Super Heavy. Presumably there would be huge benefits if it could belly flop also. Is this the case and why is Elon not pursuing it? Aerodynamics could be solved by hiding a short nosecone in the Starship body. This would mean moving the engines higher and increasing the length of Starship.

 

[mongo]

Just thinking about Super Heavy. Presumably there would be huge benefits if it could belly flop also. Is this the case and why is Elon not pursuing it? Aerodynamics could be solved by hiding a short nosecone in the Starship body. This would mean moving the engines higher and increasing the length of Starship.

SH is going much slower and can engine brake, like F9 1st stage. Grid fins provide additional aerobraking.

First stage: altitude
Second stage: horizontal speed

 

[HVM]

S_#--8 Static Fire:

 

[HVM]

That was pretty cool, watch how they are build: Rocket scientist using precision tooling.