 The aircraft was built in three series, the Series I was the initial production variant which did not have trailing-edge flaps, seventeen built.Thirteen Series II variants were built with split flaps and the Series III (19-built) was similar but had detailed improvements.Each series of the Envoy was sold with a choice of engines including the Wolseley Aries, Armstrong Siddeley Cheetah V or Armstrong Siddeley Lynx IVC radial engines.