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0 pointsWJW5y ago0 comments

Technically it's more the time that the acceleration is applied for, but I see what you mean. I used to work as a weapons engineer for the Dutch navy and they were quite involved at getting the Vulcano (https://www.leonardocompany.com/en/products/vulcano-155mm) rounds working at the time. IIRC the larger caliber rounds were subjected to about 40.000g at peak acceleration though you could vary the amount of powder so actual acceleration varied. The HW guys had all sorts of trouble with exotic problems like getting the chips to stay attached to the solder pads etc.

Totally agree that the SpinLaunch system does not seem sufficient to get a payload to space though, let alone if it also needs to bring propellant for circularizing their orbits.

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mlindner5y ago

They apparently tested spinning everyday objects up to 10,000g, which is great, but I wonder if they thought about bending moments induced when the thing is suddenly released.

marsokod5y ago

And the mechanical and thermal shocks it gets when it passes from the vacuum chamber to the atmosphere.

IMHO the centrifuge part is the easiest of their challenges.

clnhlzmn5y ago

That's what seems to me to be the biggest challenge too. Going from vacuum to 1 atm at 4000 mph has got to be quite a shock. Might as well just smash the thing into a wall.

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viraptor5y ago

Do you know if that was fully custom hardware? Or what I'm specifically asking is: was the problem that the available hardware is not produced to withstand 40kG, or that they can't produce hardware able to withstand it? Because there latter sounds like a serious problem, but the former sounds like it could be solved with money spent on it.

WJWOP5y ago

For cost purposes they started out with mostly off-the-shelf components and then they slowly replaced those components that could not withstand the stress with custom kit. IIRC just casting some components in sturdy resin was often enough. Bad for the thermals ofc, but it only needed to run for a few minutes anyway. I left the navy a few years ago but since the product is now apparently ready I assume that they managed to solve all remaining problems. (Acquiring a GPS signal quickly enough from a high speed projectile was not trivial either)

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