What happened
On the afternoon of the incident, a Fairchild C-119G airtanker was assigned to combat a wildfire located approximately six miles west of Castle Crags State Park, California. The aircraft departed from Siskiyou County Airport (SIY) as part of a coordinated aerial response that included several other airtankers, a leadplane, and an air attack unit.
During the operation, the leadplane provided critical navigation data to the incoming fleet, specifying approach and departure routes, target elevation of 4,500 feet, and instructions to cross a specific ridge at 6,600 feet. The flight conditions were reported as having good visibility and no significant turbulence, aside from a minor bump near the fire's head.
Following a successful initial drop by another airtanker, the leadplane directed the subject aircraft to perform its drop. The crew followed an approach path similar to the previous aircraft, navigating through a saddle and down a creek toward the fire. As the aircraft reached the uphill side of the blaze, the crew reported difficulties maintaining the necessary airspeed before releasing their retardant payload.
Findings
Immediately following the release of the retardant, the aircraft suffered a massive structural failure. The right wing separated from the airframe, accompanied by the loss of the left wing tip and the tail booms. The remaining fuselage, which retained both engines and the majority of the left wing, struck the terrain and burned upon impact.