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  On 12/6/2017 at 11:32 PM, Kerbal01 said:

SpaceX posted about how the booster and capsule are "flight proven" doesn't show a pic of the sooty first stage. REEEEEEEEE

 

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That's because the picture was taken on the way up.

The "pinstripes" on the lower half of the reused first stage are weld inspections. You have to scrub off the soot before you can do an electromagnetic inspection of the underlying Al-Li weld. But they only scrubbed off what they needed to.

Estimates say about 2.5 kg of total soot on the first stage, which is only a ~250 gram reduction in payload to LEO, so the mass isn't an issue.

Are we sure the FH core is coming down on OCISLY? The Roadster is pretty low-mass; even for a trans-martian injection burn, the center core may have enough dV to boostback.

I wonder what the odds are that the upper stage jettisons the Roadster, does a nitrogen-thruster flip, and burns backward to come back for an entry attempt. Just enough of a burn to bring it into an aerobraking trajectory, with PICA-X panels covering the PAF and fairing-style steerable chutes tucked around the Merlin Vac.

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  On 12/6/2017 at 11:52 PM, sevenperforce said:

I wonder what the odds are that the upper stage jettisons the Roadster, does a nitrogen-thruster flip, and burns backward to come back for an entry attempt. Just enough of a burn to bring it into an aerobraking trajectory, with PICA-X panels covering the PAF and fairing-style steerable chutes tucked around the Merlin Vac.

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It’ll be an 11km/s reentry, way hotter than Dragon LEO reentry. Also, drained upper stage is probably aerodynamically unstable and will flip engine-first. I also doubt that it is strong enough to withstand the g-load from TMI aerobraking.

Edited by sh1pman
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  On 12/6/2017 at 11:42 PM, StrandedonEarth said:

They posted it beside the BulgariaSat landing video :cool:

that was a joke 

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Beat me to it. Just wait, the flight will go up with a big black “CENSORED” box over the booster. Wouldn’t do to go showing their dirty rockets to the public, now. <_<

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  On 12/7/2017 at 12:00 AM, IncongruousGoat said:

I would assume so, just to demonstrate the capability.

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....but why not demonstrate the capability to RTLS?

  On 12/6/2017 at 11:58 PM, tater said:

Is there a third landing zone at the Cape?

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90% sure there is.

  On 12/7/2017 at 12:10 AM, sh1pman said:

It’ll be an 11km/s reentry, way hotter than Dragon LEO reentry. Also, drained upper stage is probably aerodynamically unstable and will flip engine-first. I also doubt that it is strong enough to withstand the g-load from TMI aerobraking.

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The US will probably have enough spare prop to brake by at least 2 or 3 km/s before entry. And the engine bell may act as a shuttlecock.

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  On 12/6/2017 at 11:58 PM, tater said:

Is there a third landing zone at the Cape?

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Only two, and the second one is just getting finished or will be “soon™.”

  On 12/6/2017 at 11:52 PM, sevenperforce said:

Are we sure the FH core is coming down on OCISLY? The Roadster is pretty low-mass; even for a trans-martian injection burn, the center core may have enough dV to boostback.

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I really doubt it’s gonna be just the roadster, this is a capability test too after all. I expect lots of instrumentation and still some common ballast. 

  On 12/7/2017 at 12:10 AM, sh1pman said:

It’ll be an 11km/s reentry, way hotter than Dragon LEO reentry. Also, drained upper stage is probably aerodynamically unstable and will flip engine-first. I doubt that it is strong enough to withstand the g-load from TMI aerobraking.

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This. Recovering the upper stage sounded iffy enough to begin with just from LEO velocity. Since we’ve heard nothing else, I expect that plan’s scrapped, unless they sourced some kind of transfer stage for the Tesla. 

  On 12/7/2017 at 12:13 AM, sevenperforce said:

The US will probably have enough spare prop to brake by at least 2 or 3 km/s before entry. And the engine bell may act as a shuttlecock.

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The engine bell would get torn apart in very short order. That thing is incredibly fragile when it’s not firing. 

 

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