I was thinking through a few things and had an idea for a possible launch method for satelites or other payloads that need to acheive escape velocity.

You'd need to build a large tube from the surface of the ocean to the base and allow it to flood.
Your payload would have to be buoyant (possibly by adding air pockets/foam/etc).
By adding weights to the payload it would sink to the bottom of the tube. By then releasing these weights the payload would launch due to its buoyancy.

As I see it the advantage would be once the tube was built each launch is essentially "free".

Could this work? Would the payload gain enough speed to escape the atmosphere? Is there any obvious reasons that this wouldn't work?

I realise that this is a bit of a long-shot but the idea interested me.

Cheers

i dont think it would work, what i do think would work is leaving the tube open, placing the satelite in the tube, and then opening the tube from the bottom and letting the water rush in. that could theoretically produce a force large enought to launch a small satalite.

Excape volisty is over 2100 MPH Theres No natrial way on earth or any other planet to creat this kind of energy .Even the winds of satern arenot that fast at 1200 mph .
you would be lucky to get 200Mph by eartheer way you tryed that.
a dought water could flow much faster then that given just an open toob.
humm terminal volicety plays into this as well .
a cloud 2000 feet up starts producing rain the rain falls at much less the 100mph any faster any it would not be good.lol

friction and resitance are the greatest drawback to this method. if this were feasable I think they would have used it for submarines long ago to launch missiles

A Canadian scientist named Bull who worked for the Iraqis quite a bit had an idea which was interesting and would probably work. His idea was to use a specially designed artillery cannon for launching small payloads. You could theoretically launch small components of a larger payload which could be steered to a space station and assembled in space for larger launches. It would reduce the shuttle to primarily a manned-mission tool.

I believe its somewhere around 21000 mph for escape velocity, the shuttle travels at around 17,000 mph.

As for a linear accelerator, I believe a corkscrew might do the trick. Basically, as it makes one rotation, it moves the satellite one full length of itself.

Let's say you have a one foot sphere satellite, real small. And the pitch or angle of the screw is enough to move the sphere one foot for every rotation. Probably 45 degrees, but not sure. So as you spin your screw, you ramp up acceleration for your sphere. So you just calculate the RPM needed to send your sphere into space.

Imagine two low friction rails with the screw between them, and the sphere rides on the rails being pushed along by the screw. You may need some rails on top to keep your sphere from flying off. A simple jet engine or smaller could probably get it aloft.

The system could probably scale up to accomodate larger loads, bigger screw and drive motor.

If you think I'm crazy, just look at your average vending machine. The pitch in those screws is shallow so the candy doesn't move forward too fast, and they're only shallow to get more candy in there.

Billion dollar idea....who can build one....

Thanks for the link Countermeasures.