On a serious note though, the folks out a Nellis AFB NV (at least when I saw them last in 1990) had a compressed-air catapult for the Mig27 (or was it a Mig29...can't remember) rear prop RC plane they had that was used for the aerial gunnery course. Not quite sure how it was all arranged, I was to busy shooting at the time :P I do remember that the aircraft had about a 48" wingspan