RE: 69" QQ Yak-54
Hey Reza,
I really like the way the Yak 69" is so light, and it looks like exactly what I'm looking for. I have an old YS 120 AC that pulls like a horse. Right now I have it on an old Goldberg Sukhoi that weighs 10.5 lbs with 28 oz/ft^2 wing loading, and the vertical capability with this engine is unlimited. The problem however, is the high wing loading, which makes the plane very ponderous and sluggish. This is what makes the Yak 69" so attractive.
Would the YS 120 AC be a good fit for the Yak 69"? The engine weighs about 32 oz without muffler, and I would use a Slimline Pitts style muffler if I put the engine in the Yak 69". I would also like to mount the tank close to the CG. Would this be a problem?