Guys
i have a plane which should take a .20 minimum. what weight do i need to get this thing down to for the os15 to cope with. its a trainer by the way.

thanks
andy

Some details perhaps? Wing span? Wing area? There is no specific weight beyond which the motor ceases to work.

In general? You'll want a model not much over 2-2.5lbs based on 350-400 in/sq wing. Lighter is always better. You can save significant amounts of weight by using mini-servos & rx in a plane this size, well as replacing NiCd batteries with much lighter NiMh cells.

If you look after the ounces....the pounds will take care of themselves.

'Race

its a duraplane 20. span 44" , area 440 sq i and weights 2.2lbs w/out rc gear.

andy

OK Andy....

You're going to be in the 3lb+ range in my estimation with standard radio gear (and fuel) added.

As I mentioned in my first post, strive to install the lightest suitable radio gear you can. I really think this model will be on the low end of the performance curve...bordering on marginal with the .15 installed. For a basic trainer...there's a point where being too low powered can take expert skills to avoid a unscheduled meeting with the ground!

Best bet is to give it a try and see how it pans out. Duraplanes are pretty rugged.

If it is at all possible to install a slightly larger motor...do so.

'Race