That is hard to answer because of the great variety of models. Some planes have low wing loadings and large wing areas that can fly with a small engine while a higher wing loading from a smaller wing area means a hotter plane. Motorgliders and Old Timers could be 550 to 600 sq. inches wing area. The biggest I have seen is the acrobatic slowflying Puddle Jumper with 800 sq. in. area. Trainers go from 325 to 425 sq.inches while I learned on a Tooter which had a 600 sq. inch wing. A hotter plane, like the House of Balsa Extra 300L has 280 sq. inch wing. I think it makes more sense to pick the model first and then to select the appropriate engine.

Definitely use smaller than standard servos which can be a big weight saving.


Dave Segal