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Skylon

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I'm guessing we won't see many land landings in the future, just mainly barge landings.    I would assume that a land landing would mean a lower payload, and that would indicate SpaceX had more capacity for that flight, and is therefore 'leaving money on the table' as it's called.  Of course, a large lightweight payload would be a different story.

 

And I'm still amazed at the barge landings.     They know roughly (within a few hundred meters I would guess) where the booster will land, and they just stick a barge out there.   And the booster finds it.    Insane. 

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In theory, fairing capture should happen at roughly the same T+ time on every mission. Anyone know what that time is? I believe it's somewhere around T+50.
EDIT: Answered my own question. Happened at T+ 40:15 on one of the starlink missions.
EDIT2: T+ 39:00 and T+ 41:00 for Koreasat.

Edited by ExtremeSquared
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20 minutes ago, Kevin Kyle said:

I was expecting it to just continue forward but it looked like it yawed right. Maybe its just my old eyes but that wasnt what I expected.

They sometimes set Stage 2 on a yawing spin before releasing the payload.

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1 hour ago, Gargamel said:

I'm guessing we won't see many land landings in the future, just mainly barge landings.    I would assume that a land landing would mean a lower payload, and that would indicate SpaceX had more capacity for that flight, and is therefore 'leaving money on the table' as it's called.  Of course, a large lightweight payload would be a different story.

 

And I'm still amazed at the barge landings.     They know roughly (within a few hundred meters I would guess) where the booster will land, and they just stick a barge out there.   And the booster finds it.    Insane. 

The planned Space-X drone ships configuration.

(Including the fairing catchers and the ASDS rocket bases.)

Spoiler

1024px-Baseball_positions.svg.png

P.S.

When will they start redirecting useful asteroids to the Earth, attach chutes, and catch them with bigger version of the fairing catchers?

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5 hours ago, Deddly said:

The thrust puck appears to merely distribute the weight to the outer shell anyway, I don't see a benefit to having the landing impact added to the already considerable stress that point is under. 

It distributes the force of the engines to the outer shell, which is the primary thing lifting the entire ship. So transitioning from engine thrust force to impact force would be natural.

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13 minutes ago, sevenperforce said:

It distributes the force of the engines to the outer shell, which is the primary thing lifting the entire ship. So transitioning from engine thrust force to impact force would be natural.

That's what I mean, though. Why attach legs to the puck, which transfers the load to the shell, when you can more easily attach them directly to the shell? 

3 hours ago, Gargamel said:

 

Yeah... it's still doing it.   

 

If there was an answer earlier in the thread, if somebody would kindly point it out.   Thanks. 

 

 

 

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9 hours ago, sevenperforce said:

It distributes the force of the engines to the outer shell, which is the primary thing lifting the entire ship. So transitioning from engine thrust force to impact force would be natural.

What is that max acceleration of Starship + Super heavy? I'm guessing around 30-40m/s2 shortly before separation?   What is the load path?  My guess is through the skirt, but that is just a guess.

What is the acceleration of a fully fuelled and loaded Starship?   About 10m/s2 or so isn't it?  So the thrust puck only needs to be designed to cope with stresses equal to a fully fuelled and loaded starship at just over 1 gee, whilst if my guesses above are correct, the skirt needs to support a fully fuelled and loaded Starship at around 3-4 gee.  

Additionally, in the event of a heavy landing, if any damage is confined to the bottom of the skirt, then there is less risk of a fuel leak and subsequent fire than if the thrust puck is deformed or the downcomer is damaged or the bottom of the lox tank is damaged.  

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39 minutes ago, RCgothic said:

Take a look at these pics. This doesn't look good. I wonder if they did some modifications to get the Raptors under there? Doesn't look like good practice at all.

Seems like taller pipe stands would do the same job with less danger. Failing that, just wheel the vehicle to the pad and install the engines immediately after.

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This series of French tweets has a good round up of pictures:

 

"Assembly of SN10 and SN11 prototypes continues as one section prepares to recurve a large quantity of heat shield tiles."

 

I'm quite psyched to see what a large collection of tiles looks like. The lunar starship mockup also has a curtain round the bottom, so I'm sure there's lots of work going on in there.

 

"The SN9's fins were damaged following the incident with its mount, and will certainly be replaced if the prototype remains essentially in good condition.

The nosecone of SN10 is in the LowBay and the domes are multiplying."

 

The top fin is totalled. Hope the few dents in the cone don't matter much.

Note that the stand (I *think* is the same stand from before - no damage?) is still being held down by chains and rolls of sheet metal. I... Don't think that's a great idea.

"On the launch site, launchpad n ° 2 is ready to potentially host SN9.

Work is resumed on the orbital launch pad and a new crane is being assembled."

 

The damaged tent had been stripped. Guessing it needs all-new canvas at a minimum. The orbital launch pad seems to be getting wooden shutters. Good to see some progress, it's been a while.

Edited by RCgothic
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19 hours ago, Gargamel said:

I'm guessing we won't see many land landings in the future, just mainly barge landings.    I would assume that a land landing would mean a lower payload, and that would indicate SpaceX had more capacity for that flight, and is therefore 'leaving money on the table' as it's called.  Of course, a large lightweight payload would be a different story.

 

 

If its a geostationary transfer orbit, it needs more delta V and more fuel. Similar for a heavier satellite. 

But if the satellite isn't so heavy, or the orbital requirement not so great, effectively they have "excess" payload capacity, which translates to enough space/capacity for a bit more fuel. So they can choose to put a bit more fuel on, to get the stage 1 boosters back to land, rather than drone ship - since the cost of that fuel outweighs the cost of transporting that booster + barge back home.

The barges go quite far "out" into the Atlantic to get underneath the stage 1s. Think, in KSP when you're launching a rocket, a few minutes in you're on a sub-orbital trajectory with a big curve covering maybe 1/8-1/4 of the planet. 

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39 minutes ago, RCgothic said:

The top fin is totalled, but the mounting doesn't look too bad with it removed. Hope the few dents in the cone don't matter much.

The nosecone without flaps isn't SN9's, it's probably for SN10. We'll see the damage on SN9's flap mounts if they remove the flaps.

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2 minutes ago, RCgothic said:

Good catch, that one's in the windbreak, not the highbay.

Nobody's really settled on a name for the smallest assembly building yet. Some call it the wind break, others call it the small bay.

Personally I'm partial to Smol Bay :sticktongue:

48 minutes ago, RCgothic said:

Note that the stand (I *think* is the same stand from before - no damage?) is still being held down by chains and rolls of sheet metal. I... Don't think that's a great idea.

Looking at it closely, it looks like it's on the same stand as before, just being stabilised by the crane. I think a new mount arrived recently but SN9 hasn't been mounted on it yet.

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