What happened
A C-141B aircraft was performing a multi-leg mission originating from Norton AFB, with a planned stop at Peterson Field. During the initial segment of the flight, the crew was forced to abort the mission and return to Norton AFB because of a leak involving a comfort pallet.
Upon completing the second leg of the journey toward Hurlburt Field, the crew encountered significant thunderstorms obstructing the primary instrument landing system approach for runway 36. To avoid the weather, the flight crew requested an alternative TACAN approach for runway 18, which required flying over low-lying, swampy terrain.
During this maneuver, the aircraft began a rapid descent that triggered Ground Proximity Warning System (GPWS) alerts. Although the co-pilot reset two separate GPWS warnings, the aircraft continued to descend below the established Minimum Descent Altitude of 345 feet above ground level. The C-141B eventually struck the ground while maintaining a nose-low, wings-level attitude. There were eight fatalities among the occupants of the aircraft.
Findings
The investigation determined that the accident was the result of controlled flight into terrain.