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25 minutes ago, sh1pman said:

Should call it "The Trampoline".

Whatever they call it I'll be sorely disappointed if they aren't playing "Catch a Falling Star" when it does its trick.

Edited by HvP
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2 hours ago, tater said:

Seems pretty doable with an expended booster, but the #dearmoon implies some sort of soft touchdown for the booster since they use the same stage sep time as the first orbital test. The orbital test has a boostback, but NOT RTLS. I would imagine as a full test of SH, they want to send SS to orbit using the props SH would nominally use, so it likely touches down with residuals for that little bit of unused boostback with the at sea landing (ASDS or not).

One possibility is that SN20 doesn't have all the mass savings that they want it to have, and so it needs an extra boost to get into the test orbit they want, and so they are going to expend the booster.

But that makes very little sense; they should have plenty of margin simply by not carrying payload.

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We know the payload to LEO implications of Expended vs ASDS (at sea) landing, vs RTLS landing for F9.

Full payload (expended), ~80% payload w/ASDS landing, ~60% payload with RTLS.

As we see with the back of the envelope math up thread regarding #dearMoon, small changes in payload can make a profound difference in possible mission profiles with a single launch.

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13 hours ago, sevenperforce said:

One possibility is that SN20 doesn't have all the mass savings that they want it to have, and so it needs an extra boost to get into the test orbit they want, and so they are going to expend the booster.

But that makes very little sense; they should have plenty of margin simply by not carrying payload.

They does most of the boostback, I see two options first they are not sure about the flight performance of superheavy so they will do an water landing. 
Or they wait until they can grab it who imply they are willing to burn trough a lot of raptor engines. 
Not only do they need to buid the catcher, they also need to get the accuracy needed and I kind of think they need hot gas thrusters for this, if you miss you can easy damage the launch platform and tower. 

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9 minutes ago, magnemoe said:

Not only do they need to buid the catcher, they also need to get the accuracy needed and I kind of think they need hot gas thrusters for this, if you miss you can easy damage the launch platform and tower.

Iirc right now it takes them about 1.5 weeks to build one section of the tower, which means that if a superheavy destroys the OLT it would take them 2 months and a half just to make the new sections, let alone mounting them and the integration/catching mechanism. They definitely want to avoid that

Edited by Beccab
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If you are falling you usually stick your legs out and catch yourself like a normal person. Now imagine you are falling but their are two parallel beams on each side of you, instead of using your legs to land like a normal person, you grab these beams and try to support your weight. Turns out nobody’s arms are that strong to catch them while falling so they end up bending upwards and dislocate. This is what I fear will happen to superheavy if it tries such a feat, it’s gridfns will simply bend upwards and shear. 

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A human also can't lift anything to orbit, so it's not exactly a fair comparison. The ball and socket joint of the shoulder is pretty weak (I would know, dislocated it twice pole vaulting in highschool), but they won't be using a joint like that. It's gonna be a joint similar to falcon 9, just way beefier.

Edited by .50calBMG
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3 minutes ago, SpaceFace545 said:

But in reality it makes 0 sense

Just ... sit down and think a bit about your qualifications for saying that, compared to the qualifications of the people working on it full-time. I've noticed that quite a lot of your posts could have done with such a little evaluation before hitting the "submit reply" button.

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