Giant catapult defies gravity by launching satellites into orbit

As much as I like the concept, I got a little concerned over the math, and found this 2022 article [0] which lays out some of the challenges. To boil it down:

> Problem #1: Can the payload survive spin-up? [...] At its full-scale size and with a desired exit speed [...] just before the payload is launched, of somewhere between 50,000 and 100,000 gs [...] This represents a peak acceleration that’s eight times what the current prototype experiences.

> Problem #2: Traditional liquid-based rocket fuel cannot be used. [...] if you have a liquid-based fuel on board, you need a plumbing system to contain and control it; this is exactly the type of system that will not survive the spin-up accelerations that SpinLaunch requires.

> Problem #3: Piercing the mylar sheet preserving SpinLaunch’s vacuum could destroy the payload. [...] the launch vehicle will strike the mylar sheet with 25 times the kinetic energy of current tests [...] “hitting a wall” of atmosphere

> Problem #4: The atmospheric drag force experienced by the payload will be tremendous. [...] The payload will be moving at its fastest where the atmosphere is the thickest, which maximizes speed and energy losses due to drag. This will also heat up the payload substantially, and in ways that no payload that’s ever made it to space before has experienced.

> Problem #5: Gun-based ballistic launchers can achieve much greater exit speeds than SpinLaunch.

[0] https://bigthink.com/starts-with-a-bang/physics-spinlaunch/

Lots of discussion over the years:

SpinLaunch just catapulted a NASA payload into the sky for the first time (35 points, 2 years ago, 10 comments) https://news.ycombinator.com/item?id=33112413

SpinLaunch completes first test flight with rocket-flinging launch system (251 points, 3 years ago, 219 comments) https://news.ycombinator.com/item?id=29198589

NASA will test SpinLaunch's ability to fling satellites into orbit (203 points, 3 years ago, 199 comments) https://news.ycombinator.com/item?id=30996665

SpinLaunch is building a centrifuge to launch satellites into orbit (95 points, 4 years ago, 143 comments) https://news.ycombinator.com/item?id=25204660

SpinLaunch raises $40M to build a machine to catapult objects into space (103 points, 6 years ago, 105 comments) https://news.ycombinator.com/item?id=17317688

Space catapult startup SpinLaunch comes out of stealth (88 points, 7 years ago, 110 comments) https://news.ycombinator.com/item?id=16439835

Nothing to see here, folks.

The highest successful altitude achieved to date is 9.1km. According to Wikipedia, it needs to achieve 60km to launch a payload into low earth orbit. In May 2024, they replaced their CEO. "As of August 2024, no further test flights or other technological accomplishments have been reported by SpinLaunch since its 2022 test flight."