Helicopter pioneer Frank Piasecki, who died two weeks ago at age 88, leaves behind a lasting legacy in the rotorcraft world. Piasecki is well known for developing the Army’s CH-47 Chinook and the Navy’s CH-46 Sea Knight twin-rotor helicopters, which are both now built by Boeing’s rotorcraft division in eastern Pennsylvania.
He was the president and chairman at Piasecki Aircraft, a company he founded in 1955 to continue research and development of advanced vertical takeoff and landing (VTOL) technologies. These efforts resulted in the successful development and flight testing of many innovative experimental aircraft, including the Sea-Bat VTOL drone, the Aerial Geep flying car, the Ring-Tail high-speed compound helicopter and hybrid heavy-lift aircraft. Piasecki was awarded more than 25 patents in the aerospace field.
Piasecki’s latest projects–the X-49A vectored-thrust ducted-propeller compound helicopter and two VTOL unmanned aerial vehicles being developed for the Army–will continue despite his passing. The X-49A is a second generation of the company’s Ring-Tail ducted-fan compound helicopter technology that replaces the conventional helicopter tail rotor. Besides providing antitorque and yaw control, the VTDP also provides forward thrust and thrust-vectoring control, allowing for deft maneuverability.
According to Piasecki’s longtime colleague, Joseph Cosgrove, the X-49A program has completed Phase 1 flight testing, during which the modified SH-60F helicopter reached 180 knots and explored sideward flight and hover, vibration and load testing. The next step, Cosgrove said, is to clean up the Speed Hawk with retractable gear and other aerodynamic refinements to increase its top speed.
The Class II and III UAVs for the Army’s future combat system (FCS) are also progressing. Piasecki’s Class II UAV, dubbed the Air Scout, has a tandem shrouded-rotor configuration and builds on the technology developed for the Aerial Geep. The UAV could serve as a reconnaissance, security/early warning and target acquisition platform for the Army. Piasecki’s Class III UAV, the Air Guard gyrocopter, is a multifunctional aerial combat support system capable of providing reconnaissance, communications relay, security/early warning, target acquisition, designation and mine-field detection. It will be capable of taking off and landing in unimproved areas.