 After the cancellation , the Army conducted an evaluation of the seventh Cheyenne equipped with the AMCS flight control system . The testing showed the AMCS removed most of the remaining control problems , improved stability , improved handling , and decreased the pilot workload . With the AMCS , the Cheyenne reached a speed of 215 kn ( 247 mph , 398 km / h ) in level flight and in a dive achieved 245 kn ( 282 mph , 454 km / h ) ; it also demonstrated improved maneuverability at high speeds . Prototype # 7 was the last Cheyenne to fly . Lockheed had counted on the Cheyenne to establish itself in the helicopter market with its rigid rotor technology , but the ambitious project was unsuccessful . The firm did not pursue development of another helicopter . 
