Impressive
Quite a game you have there, I have to say. You seem not to have any problems with ideas, which is the most important thing. Executing your ideas is another thing, you have some issues to resolve there, but you are totally on the right track. OK, where to start from. Controls menu - should clarify that on rollover you get info about controlls, because people are lazy and they might miss that. Funny thing is - I didn't find a "back" button in this menu, so I had to close the window and open the game again to play it. Maybe there is but I couldn't see it. Another thing - controlls on the first seed were not working very well all the time, sometimes it allowed me to move it up just a little so I had to press on it like 15 times to get it to the height that I wanted. Check this one out if you can. The catapult grapics on ejection didn't seem realistic - it looked like you're going to fall down and in the next second you're flying high.
I know you spent quite a while on the graphics and they are good, but not great, you should work on that a little more.
Overall - despite the problems with controls and everything else mentioned, you have an excellent game concept. I salute you and I wish you good luck from now on.