 The first of two aircraft ordered by the Army, initially designated the Model 59K Skycar (and later renamed Airgeep) by Piasecki and designated VZ-8P by the Army, flew on 22 September 1958.It was re-engined with a single Turbomeca Artouste IIB turboshaft replacing the two piston engines, flying in this form in June 1959.After being loaned to the U.S. Navy for evaluation as the Model 59N where it was fitted with floats, it was returned to the Army and its engine replaced by a lighter and more powerful Garrett AiResearch TPE331-6 engine.