First flown in 1956, the ROE Rotorcycle was an innovative, collapsible, air-droppable one-man helicopter developed for the USMC. While Hiller claimed that anyone could fly the craft after just a few hours of training, it was actually far from easy and Hiller chief pilot Richard Peck found each flight very exciting. ROE and Gyrodyne RON airframes apparently assigned four-digit serials in a special series.