you have plenty of power to get off the ground. 11K on a 10 x 7 isn't the problem.

Is the nose gear bent so that the plane is pointed quite a bit down? Check your radio. Maybe the servo rail came loose so that the air going over the elevator is pushing it back down. There is something SERIOUSLY WRONG if you can't get the plane off the ground at all.

Really take the time to check it over thoroughly. If you do get it into the air and there is a problem, consider the damage that could be done.

You said you fly on Army posts, correct? I just got out not too long ago and can tell you that if you fly it through a hmmwv, you'll not be a happy soldier.