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2 minutes ago, Beccab said:

S20 needs raptors

These are RBoosts, they're incompatible with S20.

Besides, we've already seen S20's Raptors, not sure where they're hanging out at the moment but there are certainly three engines designated for use on it.

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3 hours ago, tater said:

 

 

Info on that from our usual reddit insider:

- Unlike falcon 9 which pressurizes with Helium in COPVs, superheavy is autogenous (i.e. engines produce the gas maintaining tank pressure)

- Maintaining ullage pressure will be a problem with such a large tank. With a header tank, less gas is needed to maintain pressure flow for landing

- While B4 does not have that there should be sufficient gas volume tap-off produced by the engines to maintain ullage pressure, but it reduces engine performance.

Edited by Beccab
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On 10/2/2021 at 12:33 PM, Beccab said:

Info on that from our usual reddit insider:

- Unlike falcon 9 which pressurizes with Helium in COPVs, superheavy is autogenous (i.e. engines produce the gas maintaining tank pressure)

- Maintaining ullage pressure will be a problem with such a large tank. With a header tank, less gas is needed to maintain pressure flow for landing

- While B4 does not have that there should be sufficient gas volume tap-off produced by the engines to maintain ullage pressure, but it reduces engine performance.

I also suspect that having the header tanks place off center will assist Superheavy in performing a more aggressive glide maneuver on its way back, which further reduces propellant consumption during the boostback burn. Falcon 9 depends exclusively on its grid fins to provide the pitch authority for the body lift glide maneuver, but having Superheavy’s center of mass offset that means it will naturally get some body lift even in the passively stable configuration, like a capsule.

In addition, superheavy will be using its main tank ullage gas for RCS, which is another reason to keep the header tank separate. 

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He'll go to space at some point, his goal is not to put himself in space, it's to make humans a multiplanetary species. Ideally before the end of the century.

Commercial launch probably tops out at $3-$4B/yr.

If they can capture ~3% of internet would be more like $1T/yr. Revenue stream for SS and Mars.

Best case F9 marginal cost (reused) not counting overhead, etc ~$15M for 15t.

Marginal cost for SS could be <$1M/launch.

A lot to learn on the Moon, and "frickin cool." Analogous to Antarctica science labs.

LSS does 8-10 times as much as NT lander for half the price.

 

 

 

 

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I had a really vivid dream last night (pretty rare for me) that Superheavy launched, cleared the tower, but came down on the beach moments later. Coming on here in a still half-awake state to reassure myself that no, none of that was real, it wasn't even stacked with starship let alone licensed for a launch. (Also I live in the UK, not Texas. There is zero chance I'd be walking around the aftermath).

The subconscious can be a strange place sometimes.

Edited by RCgothic
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On 10/3/2021 at 12:12 PM, tater said:

A lot to learn on the Moon, and "frickin cool." Analogous to Antarctica science labs.

Making humans multi-planetary is one hell of a mission statement.

However, building bases on the Moon, and having long-term stays there is a fantastic/amazing accomplishment in itself. Hell building infrastructure on the Moon using Starships high turnaround time could make the ISS look likes child's play. 

"Frickin cool" indeed :D

 

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On 10/3/2021 at 3:12 PM, tater said:

He'll go to space at some point, his goal is not to put himself in space, it's to make humans a multiplanetary species. Ideally before the end of the century.

Commercial launch probably tops out at $3-$4B/yr.

If they can capture ~3% of internet would be more like $1T/yr. Revenue stream for SS and Mars.

Best case F9 marginal cost (reused) not counting overhead, etc ~$15M for 15t.

Marginal cost for SS could be <$1M/launch.

A lot to learn on the Moon, and "frickin cool." Analogous to Antarctica science labs.

LSS does 8-10 times as much as NT lander for half the price.

"Suborbital is a step in the direction . . . of orbit. So . . . it's still good to do something in space."

So few words. So much shade.

6 minutes ago, tater said:

 

 

So a payload delay, not an engine delay?

Hmmmmm.

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59 minutes ago, StrandedonEarth said:

Payload delay, what, is Boeing building it?

From the article "One of the spacecraft on the USSF-44 launch is a microsatellite named TETRA 1 built by Millennium Space Systems, a subsidiary of Boeing."

So, you may just be right.

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