Airplane is fine, can't say about the engine without knowing what it is and what size. The rubber bands I use are #64 (double check this on towerhobbies.com) and I put on 12. First two diagonally, then 4 back to front, last two diagonally to hold the rest on. There are two that hold the wings together, on the two small screws, these can be any small rubber band since they only keep the wings from separating when installing the wing.