Rachel, To help clear up some of the confusion, we need to know something...

Does your dad fly airplanes now?

The reason I ask is, as you've seen above, what people outside of this hobby call "Gas" engines, are what we call "Glow" engines.

"Gas" engines are much larger and are meant for much larger airplanes - usually these airplanes are very advanced and NOT for beginners.

So if your dad has been flying for many years, he may really want a "Gasoline" engine airplane. But if he is just looking to get started, He'll need a "Glow' engine airplane.

If it is indeed a glow engine plane he wants, look at RCKen's suggestions