I have a Pattern Plane designed and built around 1993, and it flies quite well - under 10 lbs, over 900 sq. inches of wing area powered by a OS .61 FSR ABC on a tuned pipe. This combination has LOTS of flights on it, and I understand that parts are not available for the engine.

My question is, what 4-cycle engine and prop might approximate the power and weight requirements for this plane? Anybody got any thoughts on this? Any ideas would be appreciated. Thanks.

A Saito 100 4 Stroke would be nice in this plane.

Enjoy,

Jim

Thanks, Jim -- I'll look into it. What prop? This is an alien area for me -- I have flown 2-cycle for 40 years!

Vaughan,

There's a lot of different props that will work. Being as this is a pattern plane, you probably should run a good bit of pitch? Something like a 12-10 or 13-10 would keep your speed up to where pattern planes usually fly. Seems like the favorite on this engine for sport planes is the 14-8. But for 3D it's more like 15-6 or 16-4 if you can find one.

There are different thoughts on what static rpm you should shoot for. Some people swear that 9,000 is it but I know the 3D guys like 10,000 with 30% nitro heli fuel in them. I just use 10-15% Omega in mine but I'm a sport pilot. The 14-6 is more of a 10,000 static rpm prop.

Other props I've seen on this engine include the bigger ones like 14-10 and 15-8 but these will keep you in the 8,800rpm area.

Oil the inside of this new engine before you ever run it. The engine will dance around and vibrate a lot when first run and in a real rich condition. After you get the needle set and it has a 1/2 gal fuel through it, it will settle down to be a nice engine.

Enjoy,

Jim

Jim -

Thank you very much for the information -- I am going to print all this out for later reference -- and fly "The Bottom Line" until I have to replace the engine.