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SpaceX launches Starship v3 rocket

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Re: SpaceX launches Starship v3 rocket

#151

Post by echoangle »

SilverElfin wrote: post #103
echoangle wrote: post #85

Earlier quoted context omitted.

They explicitly said that they have engine out capability on the ship in the stream.

That’s for the booster (the big lower part) not for starship (the upper part that continues to space). They were surprised to have a vacuum engine out. In space there’s no atmosphere so you can’t use fins or wings to change direction. And if the engines can’t move around, you only have thrust and gravity and the tiny attitude adjusters to direct your ship.

Watch the stream again starting with the ship burn. They explicitly said they have engine out capability on ship. The sea level engines on the ship are running and gimballing.

Re: SpaceX launches Starship v3 rocket

#152

Post by mrandish »

dzhiurgis wrote: post #146
ChuckMcM wrote: post #136

Earlier quoted context omitted.

Nice work by SpaceX engineering. Good summary. The booster appeared to hit the water at 1400 km/h (a bit under 900 mph) so not really survivable :-). Engine out on ship seems to left them with just enough fuel to land but not enough to do the hover thing (simulates being caught by chopsticks). They notched it down to two engines (vs planned 3) on the landing it seems? Basically if they can figure out the engine issue…

Is there videos of booster crash?

I doubt it since many of the booster engines didn't seem to relight, the location of touchdown wasn't near any pre-positioned cameras (if there were any).

Re: SpaceX launches Starship v3 rocket

#153

Post by JPLeRouzic »

s1artibartfast wrote: post #138
globalnode wrote: post #117

Earlier quoted context omitted.

Even if it landed perfectly how is it going to be rapidly reusable with all those tiles breaking and needing repair? Then if that problem was magically engineered-away through some sort of materials science breakthrough, it still makes more sense to me to keep your big ships in a space staging area and your smaller ones as atmospheric gophers.

Small ships are less efficient, especially leaving the gravity well. Thats the whole point

Could you tell me more? I suppose a heavy two-stage rocket is not optimized from the point of view of the rocket equation, but I know nothing about this field.

Re: SpaceX launches Starship v3 rocket

#155

Post by metalman »

Laremere wrote: post #15

Summary from my watch: - Launch roughly on time, after a scrub yesterday. (Sounds like the scrub was due to ground equipment, most notably the water system.) - Initial ascent was good, but then one engine on the booster went out. - Relight of the booster's engines after stage separation for the boost back burn failed. Engines did light again for a landing burn, but seems to have hit the water harder than expected and…

Booster is a totaly new rocket. It did launch with acarity and by any other standard did well, but the failure to relight could be anything, but I am going for the giant fuel feeder tube bieng the failed part, based on nothing more than how tickled they were with it,and tank baffling bieng a dark art. The slosh of the fuel durring the flip is going to produce an internal tidal wave, lots of stuff gets "tested" there.

Re: SpaceX launches Starship v3 rocket

#156

Post by LargoLasskhyfv »

dylan604 wrote: post #121
itishappy wrote: post #99

Earlier quoted context omitted.

Eh, they've left some performance on the table: > Sprint accelerated at 100 g, reaching a speed of Mach 10 (12,000 km/h; 7,600 mph) in 5 seconds. Such a high velocity at relatively low altitudes created skin temperatures up to 6,200 °F (3,400 °C), requiring an ablative shield to dissipate the heat. The high temperature caused a plasma to form around the missile, requiring extremely powerful radio signals to reach it…

I’m really struggling to find a point to this comment

Because you are speechless?

Such accelleration! Much wow!

Re: SpaceX launches Starship v3 rocket

#157

Post by p_l »

Gravityloss wrote: post #150
b112 wrote: post #132

Earlier quoted context omitted.

Just made me realise, this is just like the F-35. Its turn around time is ridiculous, it has to be maintained with specialized equipment/hangers, along with external contractor assistance. Compared to the Gripen, as an example, which can land on a freeway and be up in the air again in a few minutes. One was designed to be used in war, in desperate scenarios, with no ability to coddle it. The other, the F-35? Is desig…

I think there's also some exaggerations about the differing highway landing capabilities of various aircraft. [1] is a video showing Eurofighter, F/A-18 and F-35 all landing on a highway in an exercise. Capability with stores and fuel load is another thing but I've read material that doesn't find the contemporary aircraft drastically different in that regard. Now, maintenance hours per flight hour and general operabi…

Landing is the trivial part, though the USAF traditions of "FOD walk" do seem funny to air forces where donations you found out the aircraft spent whole day flying with maintenance toolkit left in intake.

The maintenance is the real difference - US specifically USAF gear is designed for nice air conditioned hangars to do regular maintenance, Gripen, MiG-29, and to way lower effect F-18 (when compared with F-16) - the first two assume forward bases without ability to do major maintenance, and even the latter (and other carrier adapted ones) promote things like quick swap engines because that's no space for hangar queen to have deep engine maintenance just so engine vendor can claim long time between overhauls

Re: SpaceX launches Starship v3 rocket

#158

Post by laughing_man »

globalnode wrote: post #117
itsthecourier wrote: post #114

Earlier quoted context omitted.

why won't it ever work?

Even if it landed perfectly how is it going to be rapidly reusable with all those tiles breaking and needing repair? Then if that problem was magically engineered-away through some sort of materials science breakthrough, it still makes more sense to me to keep your big ships in a space staging area and your smaller ones as atmospheric gophers.

All what tiles breaking and needing repair? There was remarkably little visible damage this time around compared with previous flights.

There's no materials science breakthrough needed -- the shuttle used ceramic tiles successfully its entire service life. What's needed is engineering work, and that's what SpaceX has been doing.

Re: SpaceX launches Starship v3 rocket

#159

Post by laughing_man »

dnautics wrote: post #82
jordanb wrote: post #76

Earlier quoted context omitted.

Shuttle's tiles not being durable as hoped is what killed it's turnaround time. The problem was never solved and turned what was supposed to be a few days into weeks or months. Every mission the shuttle had to go back into the assembly building and have all tiles inspected and potentially replaced.

Shuttle tiles were also unique per position and starship tiles have a few base forms that are interchangeable

Shuttle tiles were also bonded to the body, which I don't believe is the case with most of the Starship tiles.

Re: SpaceX launches Starship v3 rocket

#160

Post by laughing_man »

TechPlasma wrote: post #21
Laremere wrote: post #15

Summary from my watch: - Launch roughly on time, after a scrub yesterday. (Sounds like the scrub was due to ground equipment, most notably the water system.) - Initial ascent was good, but then one engine on the booster went out. - Relight of the booster's engines after stage separation for the boost back burn failed. Engines did light again for a landing burn, but seems to have hit the water harder than expected and…

I think the ship really punted the booster during stage separation. And caused the boost back failure from sloshing. Also I think Ship now has methane thrusters on it. They were operating with a clean blue flame in short purposeful bursts.

From what I've read there was "unintentional mixing of fuel and oxidizer" which caused a fire in the engine section, so the engines automatically shut down. I don't thing we have official word yet, though.
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