“The Birthplace of Rotary-Wing Flight in the United States”

Due to its long legacy of involvement in vertical flight, The American Helicopter Museum & Education Museum has proclaimed the Philadelphia area / Delaware Valley as the “Birthplace of Rotary-Wing Flight in the United States.” Here are some of the most significant vertical flight historical events in the Philadelphia area.

Harold F. Pitcairn procured and made the first successful flight of a rotary wing aircraft in America, with a Cierva C.8W Autogiro on December 18, 1928 at Pitcairn Field #1 in Bryn Athyn, PA, and in 1929 the Pitcairn-Cierva Autogiro Company of America was formed. In October 1929 autogiro manufacturing and operations were conducted from a larger Pitcairn Field #2 in Willow Grove, PA. This area is now the site of the Naval Air Station Willow Grove, and The Harold F. Pitcairn Wings of Freedom Aviation Museum.

Harold F. Pitcairn flies the Cierva C.8W over Pitcairn Field

Pitcairn Aviation had been started in 1926 and evolved into Eastern Air Lines in 1930. The historically significant Pitcairn Mailwing was created here in 1927.

The Kellett brothers, Wallace and Rod, became interested in autogiros and obtained a license from the Autogiro Company of America for the Kellett Autogiro Company with a plant in Upper Darby, PA. One of the Kellett machines went with the Byrd Antarctic Expedition in 1933-1934. In 1939 the Post Office Department contracted to fly airmail by autogiro from Philadelphia’s 30th Street Post Office roof to the Camden, New Jersey Central Airport. The Kellett KD-1B autogiro operated from June 1939 to June 1940 making five trips daily. More than 2300 takeoffs and landings were made and it had completed more than 90% of all scheduled flights.

Kellett Autogiro flying mail off the roof of the Philadelphia Post Office, 1935

The Herrick HV-2A Vertaplane was the first successful convertible aircraft

In 1932 Gerard P. Herrick became associated with Ralph H. McClarren of the Franklin Institute and constructed an experimental aircraft that would operate as a fixed-wing airplane and an autogiro. The HV-2A was a biplane with the lower wing fixed and the upper wing capable of being fixed or free to rotate like an autogiro when actuated by the pilot. It made its first flight at the Boulevard Airport in Northeast Philadelphia on July 27, 1937. By the end of the year, more than 100 flight conversions were made.

In July 1940, the Platt-LePage Aircraft Co. won the competition to build the XR-1 helicopter – the first US Army Air Corps contract for a helicopter.

Late in 1938, the First Annual Rotating-Wing Aircraft Meeting sponsored by the Philadelphia Chapter of the Institute of Aeronautical Sciences, predecessor to the AIAA, was held at the Franklin Institute. The attendees included prominent persons from the US as well as international companies involved with the development of rotary-wing aircraft. Laurence LePage showed movies of the German Focke-Achgelis Fw 61 helicopter flights. Igor Sikorsky and Arthur Young provided information on their helicopter activities. These meetings indirectly resulted in the formation of the American Helicopter Society in 1943.

The XR-1 was the first US Army Air Corps helicopter

Frank N. Piasecki of the P-V Engineering Forum investigated potential configurations and designed a single main rotor / anti-torque tail rotor helicopter. It was designated the PV-2 and after some ground testing he made its first flight on April 11, 1943 at their Roxborough facility – becoming the second US company to build a successful helicopter. Studies by the P-V Engineering Forum indicated that a tandem rotor configuration would be the most promising for higher payload capability. To support a proposed design, model testing was accomplished at the University of Pennsylvania small wind tunnel and revealed that front rotor airflow would not affect the rear rotor as some thought. The resulting HRP (nicknamed the “flying banana” because of its shape) was eventually used by the US Marine Corps, Army and Air Force.

Piasecki Aircraft Corporation (PIAC) was formed in Essington, PA in 1955 after Frank Piasecki left Piasecki Helicopter (which was renamed Vertol Aircraft Corporation). Piasecki has built numerous unique vehicles, including the VZ-8P flying truck, the “Airgeep” and a compound helicopter research design concept known as the Model 16H-1 Pathfinder that eventually reached speeds of 361 km/h.

The Piasecki 16H-1A had a cruise speed of nearly 200 knots

The Piasecki X-49 Vectored Thrust Ducted Propeller demonstrator

Compound helicopter research continued and eventually resulted in the Piasecki Vectored Thrust Ducted Propeller (VTDP) used on the X-49A SpeedHawk, which first flew on June 29, 2007. The Piasecki Heli-Stat project was created to combine the lift capability of a lighter-than-air vehicle with the precise maneuverability of the helicopter.

Boeing acquired the Ridley Park, PA-based Vertol in March 1960, forming what is now the Boeing Rotorcraft division. In that time period, extensive helicopter development occurred, including design and development of the H-46 Sea Knight and H-47 Chinook series of helicopters. The CH-47 continues in production today for the US Army and international customers; Boeing also performs upgrades of existing aircraft.

Boeing still produces the CH-47 Chinook, nearly 50 years after its first flight

The revolutionary V-22 Osprey is now in operational service in Iraq and Afghanistan

Boeing and Bell were selected to build the world’s first production tilt rotor aircraft, the V-22 Osprey, for the US Navy, Marines and Air Force.

Arthur Young living in Radnor, PA in 1931 constructed the first of many models and a whirling arm for testing propellers. A boyhood friend Bartram Kelly helped him with these initial model experiments that he believed was the best way to understand the dynamics of rotors. Both Young and Kelly were hired by Bell in November 1941, which led to the foundation of Bell Helicopter.

Last Updated: January 22, 2010