4 ms·

10k G should be doable, during WW2 the allies had radio proximity fuzes for artillery shells that exceeded that: https://en.wikipedia.org/wiki/Proximity_fuze ht

10k G should be doable, during WW2 the allies had radio proximity fuzes for artillery shells that exceeded that: https://en.wikipedia.org/wiki/Proximity_fuze https://en.wikipedia.org/wiki/Proximity_fuze

TheLoafOfBread 4y ago
What about the rest of the satellite? Solar panels, antenna, engines?
- MichaelCollins 4y ago
  It all seems generally dubious to me. But I think solar panels could survive that force if they were firmly supported inside the vehicle before launch; I don't think the acceleration itself would break the panels if they were prevented from flexing. For an engine, maybe solid fuel but the fuel itself would be structural. A pressure-fed liquid fuel engine might be easier, if you could get valves (and actuators for those valves) to survive that kind of force.
torginus 4y ago
The problem is that this thing is supposed to throw a whole second stage rocket, with plumbing, turbopumps with moving parts, and fuel that sloshes around.
- JumpCrisscross 4y ago
  > fuel that sloshes around Pressure and ballast balls.
morcheeba 4y ago
That was one design that was extensively tested and then copied. Weight was no concern. Most satellites are unique, so the same can't be done. Besides being weight critical, every failed satellite becomes space junk.
- MichaelCollins 4y ago
  If a satellite thrown by this system fails, it won't make orbit, so it won't become space junk. Even if it did make orbit; space junk in LEO isn't such a huge deal, it will fall out of the sky within a few months/years. Kessler syndrome is a popular but frequently overstated meme. With regard to weight, they say this system works best with very dense payloads. But that's only for the spin/toss stage; it doesn't account for the rocket booster needed to actually bring the satellites into orbit. As for testing, engineers don't need as much empirical testing anymore, since we have very good computer simulations now. Most of the satellites launched with this would probably be variations on a handful of designs. But I don't understand where the demand for such a launch system comes from anyway. There is only so much demand for school project cube sats; communication satellites launched this way seem dubious (not least because you can launch dozens/hundreds of them at once with a rocket like Falcon 9 or Starship)

TheLoafOfBread 4y ago

What about the rest of the satellite? Solar panels, antenna, engines?

MichaelCollins 4y ago
It all seems generally dubious to me. But I think solar panels could survive that force if they were firmly supported inside the vehicle before launch; I don't think the acceleration itself would break the panels if they were prevented from flexing. For an engine, maybe solid fuel but the fuel itself would be structural. A pressure-fed liquid fuel engine might be easier, if you could get valves (and actuators for those valves) to survive that kind of force.

torginus 4y ago

The problem is that this thing is supposed to throw a whole second stage rocket, with plumbing, turbopumps with moving parts, and fuel that sloshes around.

JumpCrisscross 4y ago
> fuel that sloshes around Pressure and ballast balls.

morcheeba 4y ago

That was one design that was extensively tested and then copied. Weight was no concern. Most satellites are unique, so the same can't be done. Besides being weight critical, every failed satellite becomes space junk.

MichaelCollins 4y ago
If a satellite thrown by this system fails, it won't make orbit, so it won't become space junk. Even if it did make orbit; space junk in LEO isn't such a huge deal, it will fall out of the sky within a few months/years. Kessler syndrome is a popular but frequently overstated meme. With regard to weight, they say this system works best with very dense payloads. But that's only for the spin/toss stage; it doesn't account for the rocket booster needed to actually bring the satellites into orbit. As for testing, engineers don't need as much empirical testing anymore, since we have very good computer simulations now. Most of the satellites launched with this would probably be variations on a handful of designs. But I don't understand where the demand for such a launch system comes from anyway. There is only so much demand for school project cube sats; communication satellites launched this way seem dubious (not least because you can launch dozens/hundreds of them at once with a rocket like Falcon 9 or Starship)