The Phase 2 program suffered through a number of delays for various reasons and stretched out to over five years. The first Phase 2 flight, of an upgraded initial prototype, was on 28 November 1977, with the first flight of a newbuild preproduction prototype on 31 October 1979. Initial Hellfire launches had already taken place by then, with first firings in April 1979. A competitive evaluation of preproduction helicopters, one fitted with the Martin Marietta sensor / targeting suite and the other fitted with the Northrop suite, was performed, with Martin Marietta winning the competition in April 1980. An initial production order for 11 "AH-64A Apache" attack helicopters was issued on 26 March 1982.