AP: Forest Service Cites Spar Fatigue In Crash
A crack started at a half-inch rivet on the left wing of a 57-year-old PB4Y-2 fighting a Colorado forest fire last July. The crack spread, and the air tanker burst into flame and crashed to the ground, killing both pilots. That was the conclusion of a Forest Service investigation, the Associated Press reported last week. The Forest Service identified the cause of the PB4Y-2 crash as fatigue and failure of the left wing's forward spar, the AP reported. PB4Ys have been grounded by the Forest Service since the crash, as have C-130As. A 44-year-old C-130A was also involved in a fatal crash last year. The PBY4 had passed required inspections, but procedures did not require checking that rivet, investigators said, according to the AP. The NTSB has not yet released a final report on the crash.