Do you know Johnny jetpack?
Johnny Jetpack is a 7 and a half foot tall puppet/dummy attached to a giant water rocket backpack. When launched, he obtains heights of 70-90 feet and speeds of 50+ miles per hour in about one second. He then plummets earthward in a dramatic fashion. This plummet includes a complex system of "parachute for Jetpack", pilot ejection, screams and flailing limbs, and on-board explosion with head detachment. The crowd is then welcomed forward to the safety line to inspect the wreckage.
They also did an Air Witch and a Johnny Non Ambulatory which seems interesting. Besides, the way the jetpack works is amazing: