This makes no sense to me. If you want to recover the rockets why not use parachutes? Guiding a parachute down, maybe with the help of some propellers, has got to be easier and more reliable than this.
even with a gigantic chute you're still approaching the ground at ~20mph. not a lot can hit the ground at that speed (and be that big) without either making it prohibitively heavy to fly, or without things breaking seriously enough it would be a write off.
