On May 1, 1942 a United Airlines Mainliner crashed within ten miles of Municipal Airport in Salt Lake City, Utah. The DC-3 Mainliner veered off course in the last miles prior to scheduled landing. Flight 4 was inbound from San Francisco and was landing at 11:31 p.m. One witness directly observed the plane as it collided with a cliff in the nearby Wasatch Mountains surrounding Salt Lake City. Visibility was nine miles at the time of the disaster. Both flight crew and passengers had a clear view of the airport. My e-book was researched and written with details of past Mainliner crashes and later United Airlines history in mind.