Wiki Super Heavy/Starship - General Development Discussion

[mongo]

S24 rollout and OLM preparations. B7 grid fins were tested. There has been some speculation online that SpaceX will not attempt a soft landing of the booster in the Gulf. I have always been of the opinion that they will attempt that; why waste the opportunity? Seeing the grid fins being tested indicates to me that they plan to use them. Of course the fins serve to guide the booster to the desired landing location, they do little to reduce velocity; that requires an entry burn and then a landing burn. But why not try?

Yeah, I'm guessing people are reading too much into the marine warning areas. The rocket zone probably includes the ballistic path if the booster (or Starship) loses power. It doesn't mean that they are planning a far down range landing.

 

[ecarfan]

I'm guessing people are reading too much into the marine warning areas. The rocket zone probably includes the ballistic path if the booster (or Starship) loses power. It doesn't mean that they are planning a far down range landing.

Sure, that makes sense, but I’m not saying I think SpaceX is planning on a soft water landing for the booster because of the marine warning areas, I think not to try for such a landing with a booster which was built with functional grid fins seems like a missed opportunity and therefore a water landing attempt will be made.

 

[mongo]

Sure, that makes sense, but I’m not saying I think SpaceX is planning on a soft water landing for the booster because of the marine warning areas, I think not to try for such a landing with a booster which was built with functional grid fins seems like a missed opportunity and therefore a water landing attempt will be made.

I wasn't saying that you were saying...
I expect as close to a normal landing as they can achieve.

 

[mongo]

https://twitter.com/x/status/1643363784017453057

Eric says SpaceX told NASA the 10th...

 

[Bobfitz1]

https://twitter.com/x/status/1643363784017453057

Eric says SpaceX told NASA the 10th...

"Good morning Mr. Nolan, Bill Nelson would like to speak with you on line 1. He seems a little agitated. "

 

[unk45]

I hope so. EM was suggesting that no landing legs will be required with suborbital BFR hops, because the landing evolution is so controlled and well-understood that the rocket can just land and mate up directly with the refueling points on the barge,
I respectfully would call major BS on that.
When pilots land an airplane, they try very hard to roll it on so the pax don't know they've arrived. Except when there's a crosswind and you need to dump lift now. Or have a short runway and need to stop now. Or because the wind shifts in the flare and you just thump it in and cringe. The runway centerline is there for a reason, and if the nosewheels don't straddle it pilots ding their performance. And don't get me started about stopping the airplane. There's a whole zen-thing about applying the brakes just so to keep anyone from feeling that natural little shudder of coming to a halt. In other words, there's the ideal (which is fine to aim for but not always achieved) and then there's the world.
Or in the case of the BFR, worlds.
Stuff happens and I would be very surprised (and impressed) if a huge ballistic object like the BFR could be brought down with that degree of unerring precision. Every time. To paraphrase one of Tesla's founders, Software is easy. Rockets are really, really hard.
Robin

Since atmospheres are gaseous and planetary rotation causes friction, any landing with an atmosphere is inherently variable. Thus no landing ever could be perfectly precise, partly because the mass of fuel expended to slow the rocket will itself always generate turbulence.
Perhaps I miss something because I've never conducted a landing without an atmosphere, however I have landed after a very long overseas flight when the forecast weather was wrong, so I suddenly faced a 30kt crosswind with no alternative within range.

Just imagine a Starship landing to a very, very precise point when the forecast was, say, two hours old, when that Starship would have no alternate.

As a non-expert I do not claim to know. As an ATP with a fair number of long distance flights I do know weather IS, so Starship will require very, very robust landing support structure. Honestly Elon knows that too, he's an experienced pilot himself. OTOH, landing on the moon would be far, far simpler.

 

[mongo]

Since atmospheres are gaseous and planetary rotation causes friction, any landing with an atmosphere is inherently variable. Thus no landing ever could be perfectly precise, partly because the mass of fuel expended to slow the rocket will itself always generate turbulence.
Perhaps I miss something because I've never conducted a landing without an atmosphere, however I have landed after a very long overseas flight when the forecast weather was wrong, so I suddenly faced a 30kt crosswind with no alternative within range.

Just imagine a Starship landing to a very, very precise point when the forecast was, say, two hours old, when that Starship would have no alternate.

As a non-expert I do not claim to know. As an ATP with a fair number of long distance flights I do know weather IS, so Starship will require very, very robust landing support structure. Honestly Elon knows that too, he's an experienced pilot himself. OTOH, landing on the moon would be far, far simpler.

Woah 2017 discussion (pre catch tower).

Earth hops would be between OLTs, no legs needed. Sub 90 minute flight and mass to surface area ratio makes control easier than a plane. Falcon 9 boosters, which lack hover ability, have done well even in rough weather.

Non-earth landings need legs (at least initally) and a flattish spot.
Moon has no atmosphere and Mars lacks density to push Starship around.

 

[ecarfan]

This graphic from @ringwatchers nicely summarizes the insane pace of vehicle production at Boca Chica.

 

[dhanson865]

7 years ago today the first successful orbital class drone ship landing (paving way to the first orbital class reuse)

Starship should be launching orbitally soon and be doing it's version of this dance.

 

[dhanson865]

https://i.redd.it/liyvgko75osa1.png

 

[dhanson865]

replies to

https://twitter.com/x/status/1644756368136589312

 

[ecarfan]

Raptor test, continuous firing for 5 1/2 minutes with extensive, rapid, thrust vectoring.

 

[Grendal]

 

[ecarfan]

Is that a new video from SpaceX? It looks familiar.

 

[mongo]

Is that a new video from SpaceX? It looks familiar.

Re-release, same as the presentation.

 

[Grendal]

Is that a new video from SpaceX? It looks familiar.

It's using elements from other presentations (BFR and Starship) and has updated them to the more modern Starship. It is from official SpaceX.

 

[ecarfan]

Is one of the updates the way that the in orbit refueling is shown with the ships side-to-side instead of end-to-end?

Do you think the tanker will have electric pumps to transfer the CH4/LOX?

 

[mongo]

Is one of the updates the way that the in orbit refueling is shown with the ships side-to-side instead of end-to-end?

Do you think the tanker will have electric pumps to transfer the CH4/LOX?

Original concept was that Starship fueled through Super Heavy. That complicated SH, so they added Quick Disconnect arm to the Orbital Launch Tower. New video is based on QD to QD connection for transfer.
As to method, minor acceleration via thrusters sideways will cause propellants to flow from one ship to the other without pumps. Pumps would need the ulage thrusters anyway. If they thrust in the normal engine direction, they could pressurize the 'from' tank to cause flow after the levels match.

SpaceX has a NASA contract to demonstrate refueling that is separate from Human Landing System. Will be unterestingto see what they go with

 

[ggies07]

Damn, I had goosebumps the whole time! LET'S DO THIS!!

 

[ecarfan]

Yesterday, Eric Berger published an article giving the latest plan for the launch.

Presently, the company is targeting April 17, at 7 am local time in South Texas (12:00 UTC) for the integrated flight test of the launch system. It should be quite a show—the combination of the Super Heavy first stage and Starship upper stage is the largest and most powerful rocket ever built.

Sources said SpaceX has been working closely with the Federal Aviation Administration to provide the necessary data about Starship's performance and its impacts on the area surrounding the launch site. There is an expectation that a launch license will be issued this week, but there is no guarantee this will happen.

SpaceX also plans one final test, a "launch rehearsal," on Tuesday. During this test, the rocket's first and second stages will be fueled as if they were going to launch, but the rocket's engines will not ignite.

Currently the road to the launch site is open and there are people working at the OLM. Seems unlikely the WDR will happen today given it is almost noon in Texas.

During this flight test, if it proceeds nominally, the Super Heavy rocket will fire for a couple of minutes before separating from the upper stage and making a controlled descent into the Gulf of Mexico. Like SpaceX did with some of its early Falcon 9 rocket first stages, the company will monitor the vehicle's performance to see if SpaceX is ready to attempt a land-based landing on future missions.

After separating from the Super Heavy rocket, the Starship upper stage will seek to reach orbital velocity before reentering the atmosphere over the Pacific Ocean. SpaceX plans to land Starship vertically into the ocean, north of the Hawaiian islands.

Screen capture from NSF live feed right now.