I just bought my first plane. It is a Hobbico superstar with an os 40la. The plane had never been flown or started. I have never flown an airplane. I took it to my local club to get some training. The instructer tried to take it for the first flight but couldn't get it off the ground. We tried bigger tires and a 10 6 and a10 5 prop. He said the motor is fine for the plane but the grass runway was slowing it up too much. He suggested I try again when the grass starts thinning or go with a bigger motor. I don't want to have to worry about checking the runway each time before I fly. He said it's kept at about 1.5" I'm running 15% nitro. Is getting a bigger motor the best choice, or do I have other options,ie fuel,prop? Thanks-Andy</p>