Piper PA-42 Cheyenne III / Cheyenne IV / Cheyenne 400LS

On 30 June 1980 Piper began production deliveries of a new version of the Cheyenne range of twin turboprop aircraft. Intended for use as a 6/11-seat corporate or commuter transport, this Cheyenne III differs considerably from its predecessors, a fact reflected in the changed company designation Piper PA-42. It has a wing of increased span, lengthened fuselage, a T-tail, and more powerful Pratt & Whitney Aircraft of Canada PT6A turboprop engines installed in lengthened nacelles. The Cheyenne III remains as a current production model, being complemented by the Cheyenne IIIA which differs primarily by having 634kW PT6A-61 turboprop engines flat-rated at 537kW and offering performance improvements. In addition to the Cheyenne III, Piper was involved in the certification programme of a new Cheyenne IV during 1983, with two 1,227kW Garrett TPE331-14A/14B counter-rotating turboprop engines, each of them flat-rated at 746kW. Deliveries of the Cheyenne IV began in the early summer of 1984. It was one of the fastest propeller light twins, at over 644km/h.

The Cheyenne is one of the very few Piper products to remain in volume production after the company's financial reorganisation in 1991/92. Current versions on offer include the Cheyenne IIIA of which 59 had been delivered by early 1993. Nine Cheyenne Ills delivered to the US Drug Enforcement Administration, fitted with AN/APG-66 radar and a ventral FLIR, are used for day- and nighttime surveillance missions. They are known as Customs High Endurance Tracker (CHET) aircraft. Cheyenne Ills are joined at the Lock Haven production line by the PA-42-1000 Cheyenne 400. Originally the Cheyenne IV, it later became the Cheyenne 400LS. Deliveries total 43.