They're claiming $500k per day and 5 launches per day, so the cost would be $500/lb. Obviously there's still an awful lot of work to be done to actually pull off that figure.

If they do pull it off, the logical next step would be to use SpaceX-style reusable rockets as well, in which case you'd save both fuel and rocket costs.

The SyFy article said "up to five launches a day at the cost of around $500,000 per paying customer," which is a bit ambiguous, but it linked to Wired which says "A ride to space with SpinLaunch will cost under $500,000 per launch."

Making the rocket reusable would be the next step, but that's a nontrivial task itself, since it's effectively the upper stage which is the hardest part of reusability. Maybe it's easier for such a small rocket, I don't know. But even then they're just shaving a little fuel off a very low launch cost, in exchange for a 200 lb max payload that has to be hardened to 10,000 gees. The launch cadence would be an advantage today but Starship is supposed to launch three times per day, if the customers are there for it.

How is Starship going? Are they still trying to “sweat” the fuel out of the skin, to give it an active cooling layer?

Starship development continues apace. They’re planning to launch the latest starship vehicle to 50km altitude next week and then perform their difficult landing maneuver 15km from the launch site.

I believe the sweating skin idea has been dropped. See this one hour video for a detailed breakdown of the current state of the design:

https://youtu.be/-8p2JDTd13k

It's being launched up to 15km, that's pretty close to 50000 feet, so you might have mixed up the units.

Oooh I see. The tweet I read said 15km/50k ft altitude and I misread that as 15km translation and 50km altitude. Thanks for the correction!

The “sweating” feature was the best idea for the spacecraft.

When I first heard of it, I was thinking, this must be a bad April Fool’s joke, or an incredibly great idea. Turns out, it was the former.

Next launch is 15km (not 50).

The latest we have is that it will sweat only where the heat shield can't hold up on its own: https://twitter.com/elonmusk/status/1107380559834046465 .

No this won't work. The founders don't understand the physics involved and their estimates of the forces involved are wildly incorrect.

Wut?

Their goal is to allow the rocket to ignite at 200k ft. Thats only a bit lower than the altitude SpaceX ignites its second stage, which is not reusable

"If Starship works out," I said. Starship reuses the second stage.

Putting aside starship, from the very limited information I've seen it's not clear that the operating costs of this system will be comparable to Falcon 9 for the booster phase of flight.

It seems like this launch system will be more expensive per kg, and have far greater loads on the payload than Falcon 9.

I hope it works out, and they find ways to make it commercially viable, but Falcon 9 really has set the bar for success quite high.

The problem isn't altitude, it's speed. Launching from the air has all the same problems of air launched rockets from planes. Except now they're trying to sling a massive rocket up to 200k feet along with all the sloshy liquids inside without anything breaking. It's complete and utter madness. The founders/investors are guaranteed to lose all their investments.

I get the scepticism, but you're not really supporting your opinions here. The first rocket was madness, the shuttle was madness, landing rockets on sea platform was madness. Sometimes mad ideas work. You'll need more details to guarantee something.

Well somebody is sure to lose their money, but if enough bigger fools can be lured aboard it needn't be the current crew. In other words, the Nikola truck but in space.

The Nikola comparison is apt here, though I think this is even worse than Nikola. There's known examples of fuel cell powered large vehicles.

Absolutely - the only thing about Nikola that looks dodgy on purely physical grounds is the claim of super-efficient electrolysis. Whereas SpinLaunch seems quite uncoupled to reality. Meaning of course the reality is that they'll run giggling to the bank...