From what information is there, I gather that the problems are a result of inexperience, in building, in flying, and in tuning power systems.

Keys to successful flying:
1. Get a plane that's designed for your skill level. Even a "beginner" plane will be a major challenge to a beginner, so don't get a WWII warbird thinking you'll get bored with the beginner plane.
2. Replace broken parts with like parts; don't use something that "looks right." Just because it's an orange prop does not mean that it's the right size orange prop.
3. If in doubt, ask quesitons before launching your plane to its potential doom