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by zionic 1362 days ago
Starship E2E (earth 2 earth) will make in-atmo supersonic pointless.
5 comments

If you’re healthy enough to withstand 3 Gs and they make rocketry about a million times safer
E2E payload weight will be much lower than typical LEO configs, total altitude lower. You don't need to circularize etc etc.

This means you can spend more fuel/be less efficient overall for a much more comfortable acceleration profile.

In terms of safety, starship will fly hundreds, perhaps thousands of times before people fly on them. They'll get there.

what’s the seat-kilometre fuel burn on this compared to sub and supersonic jets?
If passenger density was comparable to a typical airliner, an intercontinental E2E flight should be roughly comparable to a subsonic flight. The supersonic flight would be substantially worse. Rockets have the advantage that they very rapidly get out of the dense part of the atmosphere.

In reality a Starship flight would probably sell few very expensive seats instead; just like Boom's aircraft only has 50 seats. Which would make it worse than subsonic flights in terms of fuel used, but still competitive with supersonic.

Starship's payload volume is around 1000 m ^3, which should be about the same as an A380 interior volume.

For a flight time between 20 (minimum) and 40 minutes (maximum) to anywhere on earth, this volume could comfortably fit 1000 passengers per flight.

At 2 or 3 times the price of a regular ticket, their offer would be a direct competitor against business class tickets, if they can reduce enough the risk, and handle logistics of rapid reuse.

Should be much better, you spend most of the time coasting and most of your acceleration in very thin atmosphere, vs a plane that has to cruise down in the soup.

Also, starship has more pressurized volume than a 747. You can fit a lot of people.

I have a feeling most normal people will be reticent to strap themselves into a suborbital rocket.
And don't forget the required pressure suits. You can't just to use simple masks like in airplanes, since cabin pressure loss at heights beyond 25km would make breathing using just oxygen masks impossible.
And would such craft be allowed to launch from your average airport?
Does a cruise ship launch from your average airport?
Isn't the point of Starship E2E to be a fast way of travel?
The only way for sub-orbital travel to make sense is for something like NYC->Tokyo type distances. LA->NYC makes no financial sense.
A short boat ride off the coast is all it will take to get form NY to Tokyo in 40 minutes or less. Worth it.
A "short boat ride" you say... Current exclusion zones and logistical requirements suggest otherwise.

Realistically, P2P using giant rockets is a nothing but a pipe dream. Just straight forward things like weather proof this. The latest F9 launch had to be scrubbed two times due to unfavourable weather at the launch site, for example.

Now multiply that just that weather-risk by two, since the landing site also requires good conditions at the same time.

Then there's the "little things" like airspace closures, launch permissions, boarding procedures, the requirement for personal pressure suits (simple masks won't do in case of cabin pressure loss), etc.

The idea sounds so easy on paper, but there's a lot of good reasons that in over 60 years of crewed space flight, the idea hasn't even been demonstrated.

Sorry, it took me a bit to reply to you on this censorship laden bullshit “you’re replying to fast by posting more than 3 times a day” website.

Fuck dang, time to cycle residential proxies.

That said, see sibling comments about fineness. In addition to being fine in the shiny variety, starship is a portly fellow. It will be able to land in anything less than a hurricane.

F9's fineness ratio makes it very sensitive to weather. Soyuz rockets can launch in blizzards. Starship should be weather insensitive as well.

Now for the launch platform, it will have to be built about 30km from shore, and could be accessed by high speed train, the travel time would be 15-20 minutes from the shore

Don't confuse satellite launches with crewed launches. Losing a satellite due to a failed launch is no big deal, risking the lives of potentially hundreds of passengers is a different story entirely.
This is never going to happen for safety, cost and noise reasons. It's just more Musk fraud.