United Air Lines Flight 409

United Air Lines Flight 409 was a scheduled flight which originated in New York City, New York. The final flight destination was San Francisco, California, with stops in Chicago, Denver and Salt Lake City. The aircraft operating the service, a Douglas DC-4 propliner, registered as N30062 crashed into Medicine Bow Peak, near Laramie, Wyoming, on October 6, 1955, killing all 66 people on board (63 passengers, 3 crew members). The victims included five female members of the Mormon Tabernacle Choir and military personnel. At the time, this was the deadliest airline crash in the history of American commercial aviation. Another 66 lives had been lost earlier that year in the March 22 crash in Hawaii of a United States Navy Douglas R6D-1 Liftmaster military transport aircraft, and 66 had also died in the August 11 mid-air collision of two United States Air Force C-119G Flying Boxcars over West Germany, placing the three crashes in a three-way tie as the deadliest aviation incidents in 1955.

Timeline

Flight 409 left New York, New York one hour and 11 minutes late. Routine crew changes were made in Chicago and Denver. Flight 409 departed Denver, Colorado at 6:33 a.m. on October 6, 1955, 83 minutes after its scheduled departure time. The assigned path the airliner was expected to fly was along airways V-4 Denver to Laramie, Wyoming V-118 to Rock River, Wyoming radio, V-6 to Fort Bridger, Wyoming, and V-32 to a landing in Salt Lake City. The flight was operating under Visual Flight Rules and was assigned a cruising altitude of 10,000 feet. Because the aircraft was not pressurized, the altitude was chosen to keep the passengers and crew from experiencing the discomfort that flying higher could cause. The route assigned to the airliner was specifically designed to allow safe passage at 10,000 feet over the continental divide in the Rocky Mountains.

An expected position report from the United crew, scheduled for 8:11 a.m. while over Rock River, was not received, and repeated attempts to make radio contact with flight 409 were met with no response. With the airliner's status unknown, the Civil Aeronautics Authority was alerted to the missing aircraft. No radar was in place for civil aviation in this region in 1955. With no radar traces, manual searches were required to find the aircraft.