__NOTOC__ The crash of Canadian Pacific Air Lines Flight 3505 occurred on 21 July 1951 when a

Douglas DC-4 The Douglas DC-4 is an American four-engined (piston), propeller-driven airliner developed by the Douglas Aircraft Company. Military versions of the plane, the C-54 and R5D, served during World War II, in the Berlin Airlift and into the 1960s ...

four-engined piston airliner registered ''CF-CPC'' of

Canadian Pacific Air Lines Canadian Pacific Air Lines was a Canadian airline that operated from 1942 to 1987. It operated under the name CP Air from 1968 to 1986. Headquartered at Vancouver International Airport in Richmond, British Columbia, it served domestic Canadian a ...

disappeared An enforced disappearance (or forced disappearance) is the secret abduction or imprisonment of a person by a state or political organization, or by a third party with the authorization, support, or acquiescence of a state or political organi ...

on a scheduled flight for the

United Nations The United Nations (UN) is an intergovernmental organization whose stated purposes are to maintain international peace and international security, security, develop friendly relations among nations, achieve international cooperation, and be ...

from Vancouver, Canada, to Tokyo, Japan. Neither the aircraft nor the 31 passengers and six crew have been found. The incident marked the first aircraft loss during the

Korean Airlift The Korean Airlift was a military operation during the Korean War by the United States Air Force and other air forces participating in the United Nations action. Begun in 1950 under the command of Major General William H. Tunner, it provided air ...

Accident

At 18:35 the DC-4 departed

Vancouver International Airport Vancouver International Airport is an international airport located on Sea Island in Richmond, British Columbia, serving the city of Vancouver and the Lower Mainland region. It is located from Downtown Vancouver. It is the second busie ...

, Canada on a scheduled flight to Tokyo; it was due to stop over at

Anchorage Airport Ted Stevens Anchorage International Airport is a major airport in the U.S. state of Alaska, located southwest of downtown Anchorage. The airport is named for Ted Stevens, a U.S. senator from Alaska in office from 1968 to 2009. It is include ...

in Alaska. The flight was on schedule and reported at the Cape Spencer intersection in British Columbia 90 minutes out from Anchorage; it gave an estimate of 24:00 for Yakutat in Alaska. The weather in the area was heavy rain and icing conditions with a visibility of . Nothing further was heard from the aircraft, and at 00:44 an emergency warning was issued when the aircraft was overdue to report. The United States Air Force and Royal Canadian Air Force carried out an extensive search but failed to find any trace of the aircraft or its 37 occupants. The search was finally called off on 31 October 1951.

Aircraft

The aircraft, a

four-engined piston airliner had been built in 1944 for the United States Army Air Forces as a Douglas C-54A Skymaster but on delivery in June 1944 it was diverted to the United States Navy with the designation R5D-1. In 1946, it was converted to a civil Douglas DC-4 standard for

Pan American Airlines Pan American World Airways, originally founded as Pan American Airways and commonly known as Pan Am, was an American airline that was the principal and largest international air carrier and unofficial overseas flag carrier of the United States ...

as ''Clipper Winged Racer''. It was sold to Canadian Pacific Airlines in 1950.

Passengers and crew

All six crew members were Canadian. The 31 passengers included two sailors of the Royal Canadian Navy, 26 members of the United States military and 3 civilian US citizens.

Probable cause

In 1974, the

Civil Aviation Authority (United Kingdom) The Civil Aviation Authority (CAA) is the statutory corporation which oversees and regulates all aspects of civil aviation in the United Kingdom. Its areas of responsibility include: * Supervising the issuing of pilots' licences, testing of e ...

reported: "As no traces of the aircraft or its occupants has been found to date the cause of the disappearance has not been determined."

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Flying Tiger Line Flight 739 Flying Tiger Line Flight 739 was a Lockheed L-1049 Super Constellation propliner chartered by the United States military that disappeared on March 16, 1962, over the Western Pacific Ocean. The aircraft was transporting 93 U.S. soldiers and thre ...

* ''

Hawaii Clipper ''Hawaii Clipper'' was one of three Pan American Airways Martin M-130 flying boats. It disappeared with six passengers and nine crew ''en route'' from Guam to Manila, on July 28, 1938. Trans-Pacific service Pan American initiated trans-Pacific a ...

'' *

Malaysia Airlines Flight 370 Malaysia Airlines Flight 370 (MH370/MAS370) was an international passenger flight operated by Malaysia Airlines that disappeared on 8 March 2014 while flying from Kuala Lumpur International Airport in Malaysia to its planned destination ...

References

;Citations ;Bibliography * * * {{DEFAULTSORT:Canadian Pacific Air Lines Douglas DC-4 disappearance Accidents and incidents involving the Douglas DC-4 Airliner accidents and incidents with an unknown cause Aviation accidents and incidents in 1951 1951 Canadian Pacific Air Lines Douglas DC-4 disappearance Missing aircraft 1951 in Alaska July 1951 events in the United States