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Skylon

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15 hours ago, CatastrophicFailure said:

Probably not, not with orbital refueling, anyway. You’d essentially be throwing away the center core when you could get the same result (a fully or near-fully fueled Starship in orbit) for (presumably) less by just launching multiple tankers. 

Rapid reuse really will be quite the paradigm changer. :D

Also, it’s bugging the crap out of me that the “bottom” of that Starship is point off in some weird direction instead of in line with the booster mounting axis. :huh:

Note that you have the option to burn starship dry to reach orbit. This will reduce safety margins and will obviously require refueling to land but will increase payload capability. 

RTLS for all three stages makes an heavy configuration pretty pointless. 

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18 hours ago, CatastrophicFailure said:

Probably not, not with orbital refueling, anyway. You’d essentially be throwing away the center core when you could get the same result (a fully or near-fully fueled Starship in orbit) for (presumably) less by just launching multiple tankers. 

Rapid reuse really will be quite the paradigm changer. :D

Also, it’s bugging the crap out of me that the “bottom” of that Starship is point off in some weird direction instead of in line with the booster mounting axis. :huh:

As-depicted, the starboard aft fin would be inside the rightmost booster cap.

But yeah, it's useless. Notional staging velocity for a single-stack Super Heavy is ~2 km/s. Going "Heavy Super Heavy" would put the center core at 3 km/s or more and so far downrange that it would need to reserve a prohibitive amount of fuel for boostback.

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13 minutes ago, sevenperforce said:

But yeah, it's useless. Notional staging velocity for a single-stack Super Heavy is ~2 km/s. Going "Heavy Super Heavy" would put the center core at 3 km/s or more and so far downrange that it would need to reserve a prohibitive amount of fuel for boostback.

Launch from Boca Chica, recover at Canaveral. Aside from getting cooked on the way down

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11 minutes ago, Xd the great said:

Why SpaceX does not use gridfins for second stage canards and wings? They save material.

And spaceX well understands the dynamics of a gridfin, they use it.

A gridfin isn't very draggy. For Starship, they WANT draggy airbrakes.

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43 minutes ago, Xd the great said:

Why SpaceX does not use gridfins for second stage canards and wings? They save material.

And spaceX well understands the dynamics of a gridfin, they use it.

As @Rakaydos said, they want as much drag as possible on entry.

The grid fins on Falcon 9 are used because they need fine guidance and short-chord control surfaces perform better without stalling at supersonic speeds. Traditional fins (a la New Glenn) take more torque to move and stall more easily while supersonic.

In contrast, the "flaps" on Starship will be operating initially at hypersonic speeds, where everything is in a state of stall and you are using differential compressive drag to induce roll and pitch rather than any fine aerodynamic guidance. They will function less like canards and more like airbrakes.

Edited by sevenperforce
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Metal rods sticking up from the circular copncrete jig at Boca Chica. Yesterday a container arrived with the water tank company name on the side. Thought is they are about to rebuild the nose of the hopper.

Edited by tater
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