On 4 April 1975, a Lockheed C-5A Galaxy participating in the first mission of Operation Babylift crashed on approach during an emergency landing at Tan Son Nhut Air Base, South Vietnam. The cause was ascribed to loss of flight control due to explosive decompression and structural failure. The accident marked the second operational loss and first fatal crash for the C-5 Galaxy fleet, and is the third deadliest accident involving a U.S. military aircraft after the 1968 Kham Duc C-130 shootdown and Arrow Air Flight 1285.

The Lockheed C-5 Galaxy is a large military transport aircraft designed and built by Lockheed, and now maintained and upgraded by its successor, Lockheed Martin. It provides the United States Air Force (USAF) with a heavy intercontinental-range strategic airlift capability, one that can carry outsized and oversized loads, including all air-certifiable cargo. The Galaxy has many similarities to the smaller Lockheed C-141 Starlifter and the later Boeing C-17 Globemaster III. The C-5 is among the largest military aircraft in the world.