Beechcraft won the competition, and the result was a small delta-winged drone with wingtip fins and a liquid rocket motor, originally designated XKD2B-1 but now known as the AQM-37.

One high-performance variant with improved thermal protection attained a speed of Mach 4.7 and an altitude of over 112,000 feet (34 kilometers) on a ballistic trajectory.

After an evaluation of the AQM-37A in the late 1960s, the US Army bought a small initial batch of Model 1100/1101 AQM-37As that, unlike other variants, were recoverable, using a parachute system.

[5] The AQM-37's engine is built by Rocketdyne, though in some sources it is credited to Harley Davidson,[citation needed] the motorcycle manufacturer, which appears to be due to a sequence of company buyouts.

[citation needed] The engine uses storable hypergolic liquid propellants: inhibited red fuming nitric acid (IRFNA) as an oxidizer and MAF-4 as a fuel.

The tests were judged promising, and so the Air Force went on to establish a "High Altitude Supersonic Target (HAST)" program in the 1970s.