ORIGINAL: David Bathe
Because the APC is more efficient, it allows the engine to rev far higher even though it's the same size.
Well that's what the advertizing says... [)]
If the engine revs higher and the pull is less then it is simply a smaller prop with the same numbers marked on it...
(one could then compare the graupner with a "larger" APC with similar top revs and see how that flies)