What happened
On December 10, 1946, a formation of six Curtis Commando R5C transport aircraft departed San Diego bound for Seattle. The group was flying at an altitude of 9,000 feet using instrument flight rules when they encountered heavy weather over southwest Washington. Four of the planes turned back and landed safely in Portland, while one reached its destination in Seattle. However, the sixth aircraft, which was carrying 32 U.S. Marines, disappeared from radar contact.
Search and rescue efforts were severely hampered by persistent bad weather, preventing aerial operations for a week. Ground searches also yielded no results, leading to the suspension of the search after two weeks. The Navy later concluded that high winds had pushed the aircraft off its intended flight path, causing it to collide with the side of Mount Rainier.
In July 1947, a park ranger spotted wreckage on the South Tahoma Glacier. Subsequent examination confirmed the debris belonged to the missing plane. Four weeks later, search parties located the remains of the occupants high on the glacier face. Due to extremely hazardous conditions, authorities abandoned plans to recover the bodies for burial, leaving them entombed on the mountain.
Findings
The official investigation determined that the crew encountered poor weather conditions characterized by severe icing, turbulence, and high winds. At the time of the accident, the aircraft was off track due to these environmental factors.