HHHHMMMMM Won't fly eh? Sounds like a challenge to me. Here's what I would do. Have someone hold the plane and start it up at full throttle just before they throw it (tell them to throw it pretty hard). Make sure they throw it completely level if not slightly (and I mean ever so slightly down) the idea is to try and gain as much airspeed as possible. Level the plane and don't try to climb (keep the nose of the plane level) for 100 feet or so. Then try to gain a few feet (say maybe two) of altitude. If that goes well try for two more just remember slowly and gently. A slow, gentle turn (lets say to the left) is in order before it gets out of sight. A little rudder to turn and enough elevator to keep the nose level. No more no less. Keep the turn up until the plane is heading to your left. Then straighten out and try to gain a foot. Then slowly turn until the plane is coming back at you. Remember that your direction controls are now reversed. Left on the stick will send the plane to your right. Adjust your heading until the plane passes in front of you (say 25 feet in front of you). Keep doing this until you reach a 2 mistake high altitude or high enough for you to recover from a stall. I'd shoot for at least 50 feet up before I stopped trying to climb. If the plane tries to nose down, don't panic. In fact let the nose stay down a second or so to gain air speed. Pull the nose up level before you hit the ground and go back to the section above... I know this is long and there are a lot of people who would try something different, but this is the way I would do it.... Also if the plane tries to roll, turn the opposite direction. I.E. If the right wing falls, turn left some. Now if it's coming toward you, face the plane and push the stick toward the low wing. Don't let this plane fall out of the sky. Fly it all the way in. It sounds to me like this plane is somewhat out of trim and is trying to stall. The best of luck to you and by all means have fun!!!!!

Just my $.02