The Hiller Advanced Research Division (A.R.D.) incorporated a five foot fiberglass round wing, (ducted fan) with twin counter rotating coaxial propellers powered by two 44hp/4000 rpm, four cylinder opposed, two-cycle, Nelson H-59 Engines. The Nelson engine was the first two-cycle engine certified by the FAA for aircraft use. Utilizing the Bernoulli principle, 40% of the vehicle's lift was generated by air moving over the ducted fan's leading edge. The remaining 60% of lift was generated by thrust from the counter rotating propellers. Of the six Flying Platforms that were built, the (ONR) vehicle is on exhibit at the Hiller Aviation Museum, and the National Air & Space Museum.