1986–present, bought the remains of Canadair, later added Short Brothers, Lear, and de Havilland Canada. Magellan Aerospace 1996–present Rotary wing aircraft The first rotary-wing aircraft registered in Canada was a Pitcairn PCA-2 gyroplane in 1931. A later Pitcairn gyroplane model PAA-1 was registered in 1932 and for about 20 years operated in a variety of roles including barnstorming, agricultural and forestry spraying, and photography. Helicopters attracted interest from Canadian amateur experimenters ( the Froebe helicopter ) during the 1930s, but no commercial development followed. During the Second World War, the Sikorsky R-4 went into serial production, with units used by the US Navy, US Coast Guard, and British Royal Navy. Seven Canadians underwent training on the R-4. Military applications for the helicopter included anti-submarine warfare, and search and rescue. On May 11, 1945, Canadian R-4 pilot Lt. Cdr. Dennis Foley participated in the successful recovery of a downed Corsair pilot. A helicopter was used in 1944 in a search and rescue operation on the St. Lawrence River. An American Sikorsky R-4 was dispatched for the search, but the survivors were recovered by icebreaker. In 1945, another US R-4 was sent to transport survivors of a Canso crash in Labrador. US Coast Guard helicopters were again called for rescue service in September 1946, to recover the survivors of a crashed Sabena DC-4 that had impacted 30 miles southwest of the Gander airport. The RCAF acquired its first helicopter, a Sikorsky S-51, in 1947. Further helicopters were acquired by the RCAF and RCN and used for search and rescue. Many flights were carried out during the 1950 Red River flood for passengers and air photography. In 1955, helicopters of the RCAF No. 108 squadron were used in support of construction of the Mid Canada Line of radar stations. Cold War era During the 1950s and 1960s, United States defence planning viewed Soviet aircraft travelling over the Arctic as a threat, and expended much effort and money on defensive systems. Early-warning radar stations of the DEW line and Pinetree Line constructed partly within the Canadian North; construction of these stations required many air freight shipments in isolated areas. Additionally, anti-aircraft missiles called BOMARC were also stationed in Canada. These were highly controversial since they had the capability of carrying a nuclear bomb. Around 1953 Canada began development of its own supersonic interceptor aircraft, the Avro Canada CF-105 Arrow. The test aircraft achieved supersonic