Cannon shot

Allow me to think outside the box as that is where I usually am anyway,,, I am not a rocket scientist or even rocket experimenter but is there such a thing as a cannon launch. Perhaps that is not the right term but it serves my purpose for now. If we were to slide the rocket into a slightly oversized tube with a sealed bottom then on ignition the rocket would be shot out like a bullet and then the propellant would push it like a normal rocket. Should give an added boost at the beginning. Has this been tried before? It sure would help with the design of the launch pad. Perhaps some Estes experimenters could try something like this and report the results. Will an "A" motor go higher if shot from a tube or a guide rod. Does it matter?

Woody
Hey if you can make a little rocket that has an OD of less than an Inch with pop out or foldout fins we could fire it from our gas gun model and find out for ya Might be fun just for fun! I could make a little timer and igniter for it. Better make two so we could get the gas gun pressure right without turning it into shredded wheat. Go for a B motor ID

Monroe

This might trip your trigger http://www.friends-partners.org/partner ... nnched.htm

I think you missed my point. The rocket itself will provide the gas pressure in the cannon barrel launch. Imagine a bullet but backwards. The propellant stays and burns in the bullet part and not in the casing. Simplify everything. As per my queery on another topic we could rifle the barrel of the launch cannon to provide spin.

Woody
Ok, then perhaps you mean like the Loki-dart look at this launcher http://www.phy.mtu.edu/rocket/superlok.html this is 16 revolutions per second. This begins to put quite a lot of lateral G's on the payload due to centrifugal force. What do you think?

Monroe

Woody
One more thing not pushing the rocket out of the barrel would have little effect on it's final velocity unless you fire it out of the cannon then fire the rocket. Firing a rocket in a barrel would be like a bazooka, only for guidance not much for accelleration even if the end was closed the rocket would go the pretty much the same speed. If that is what you mean?

Monroe

Yes that is what I mean. I believe you would get a bit better kick getting going. Any assist in getting past the initial standing inertia would benefit the launch. Aside from that the tube would be a very simple launcher to build up which was my initial concept on this. The spin could be controlled by the rifling in the barrel. It does not have to spin at 1000 RPM
If we can make a 5" dia aluminum Rocket we can get a 6" aluminum tube to be the launcher.

Woody
One of the bigger problems will be the cold. The rocket will be enclosed in a heated container so it will be pretty much as you say I suppose.

Monroe

Can the heater be a 1/2" thick blanket? That would make the 5" rocket and 6" launcher easier. Spinning the rocket would make it difficult for photographs. Could we trail 20' of 1/16" cable behind it instead?

Woody
More Like 3" thick foam. The camera in the rocket will tilt and look around via a mirror there will be several on the platform. Their may be rails or the whole canister may spin we don't know yet. The rocket is somewhat bigger than you are thinking

Monroe

How big?

Nearly a ton.
We are just starting off small Woody.

Monroe

WHO YOU CALLING "SMALL WOODY"
I was thinking way to small. What do you figure the length and diameter of the rocket will be

Small Woody that’s funny Woody! Hey about 17ft long and 20" in diameter for the lower end and 8" at the upper end! And can carry a 10lb sat. Into orbit! Our first orbit attempt won't be an N-Prize attempt Woody. We need to get this little stuff done so we can start working on the station keeping platform that can lift 3 tons and be mostly recovered.

Monroe

We have quite a schedule coming up!.

10 lb sat. 3 ton package? Are we getting to big for our britches? I have read all your plans , dual cameras and all but I am wondering if we should keep to the minimum just to do it and then go bigger after we have won the prize. A simple sputnik beeper could be tracked around the world by ham operators. Probably get the payload down to under a pound. It would be nice to have a camera on board but lets not make it a priority. How big would the rocket package be to put a 2 lb package into orbit?
Nasa did not send a man to the moon before he sent up the first man or even the first satellite. Walk before you run etc. Small steps will get us there quicker.

Woody
Don't worry we have MANY baby steps to get to that goal! Lots of smaller test, It will be gradual progress. But our main goal has shifted because of money Woody. There is a lot going on behind the scenes to get funding and a practical launcher and station keeping launch platform are getting the nod. We won't abandon the N-Prize but I haven’t had much luck getting funding for it and we just cannot do it in this time frame with what we have. I get more bites on my Corona Ion Engine than the N-Prize by far and the station keeping platform is even better. We have to see how it goes. I do really believe the altitude record will fall for us and we will have to see where that takes us in the near future.

Monroe