Actually, I have just checked my boomerang 2 manual and it explicitly states 40-46 only, so a 52 is going to be too big unfortunately.Originally I had my heart set on Fairchild pt19 by Seagull models( I see Seagull models as basically quite good) the problem I have is the Fairchild PT19 is both complex to build and fly as it consists of 5 servo's for total control, the extra servo is needed to control ailerons independently giving separate control for each wing aileron. So the flyer gets an extra 2 functions. This plane can take 46-52 engines so the Force 52 should fit perfectly, but the engine has to be mounted upside down(due to its cowl), making glow start adapters mounted from the ground up would be a bit awkward.