Motoadve, while I am sure an OS 120 pumped would pull this bird into the sky, I think it might be a bit underpowered to push it around the skywith authority. Alot of it will depend on how heavy yours comes in after completion. Once you start adding some additional epoxy glue around the formers, qualityservos (heavier), retracts, betterwheels, a modification here or there such as upgrading the control systems with heavier duty rods or beefing the front engine compartment, you'll be adding acouple pounds at least.

From what I have read,and someone please correctme if I'm wrong,the smallest engine I've seen put in one is a 1.60 size. The few members that have actually gotten their birds into the air have had 1.60 size engines in them and they say it does very well in the air.

I myself purchased an OS 1.60 for mine. I hope to start the build in a few weeks once I finish a couple of projects I had already started before this one. It is better to have more power than needed, than to not have enough.

Hope this helps - good luck on your build.