Guns for unmanned space launches -- gee limits?

One idea I’ve heard floated around for a while is to use great big guns – either conventional, gunpowder-powered guns, or electromagnetic railguns/coilguns – to launch unmanned payloads into Earth orbit or even onto Earth-escape trajectories.

But … isn’t there some upper limit to how much “shock” the electronics on board a satellite can withstand? If I were to put a satellite and a small rocket booster into a gun capable of shoving it into the air at 1000 meters per second – fast enough to leave the atmosphere, but still requiring the rocket booster to get it up to orbital speed, of course – wouldn’t the slam of all that sudden acceleration wreck both the satellite and the rocket booster attached to it?

Or, more generally, if my satellite’s electronics can withstand X number of G’s of continuous acceleration, how many G’s of sudden (less than 1/10 second) acceleration can they withstand?

I believe that rail gun assisted launches as well as other hypothetical designs would have rails/barrels that are some kilometers long, in order to spread the impulse over a longer range and reduce the G load.

Electronics used in the radio proximity fuze shells used in WWII–the G forces involved were in the tens of thousands. Which is all the more impressive by the fact they used vacuum tubes.

Hmmm … I remember hearing about those top-secret Proximity Fuzed anti-aircraft shells on the History Channel. I didn’t notice that they had electronics on board – vacuum tube electronics, no less.

I wonder if you could build missiles that could survive that kind of initial push.

Here’s one video related to the subject, from Google Tech Talks:

http://www.youtube.com/watch?v=1IXYsDdPvbo

There was a guy, Canadian I believe, that was the guru for this sort of thing.

He was working on guns that launched shells into space/near space. And his team was putting electronics in the “shells”. Obviously the gees were damn high. The goal was cheap access to high altitudes for research.

However, the program was canceled even though they were having some success. IIRC he finally was freelancing for Sadam Hussein for that jerks mother of all artillery pieces. IIRC this canadian was eventually found murdered and some folks suspect the Israelis were the ones that knocked him off.

Ahhh…

Here is the canadian in question

http://en.wikipedia.org/wiki/Gerald_Bull