What happened
At 0857LT, an airtanker departed from Santa Barbara Airport to assist with a fire located within the Los Padres National Forest. Upon reaching the incident site, the Incident Commander (IC) provided specific instructions to the flight crew, advising them to maintain a high altitude due to the presence of snags and steep terrain. The crew was also directed to discharge only half of the onboard retardant during this pass.
The crew acknowledged these orders and signaled their final approach to the IC. During the approach, the IC observed that the aircraft engines sounded excessively revved and noted unusual cracking and popping noises. As the airtankary became visible, observers noticed that the landing gear remained retracted and the drop doors had not opened. The aircraft was traveling at a higher airspeed and a lower altitude than expected, maintaining a descending flight path.
As the plane passed the designated drop zone, it experienced a sudden vertical drop of roughly 50 to 100 feet. During this maneuver, the left wing tip snapped off after flexing downward significantly. This caused the aircraft to roll to the left and pitch down into the trees. The aircraft struck the ground at 0927, resulting in two fatalities and the total destruction of the airtanker.
Findings
Post-accident investigations by the NTSB and Forest Service recovered various components of the left wing, including the flap and aileron, scattered ahead of the crash site. Investigators identified pre-existing cracks within the inner left wing aileron bell crank control assembly. It is believed that failure of the bell crank may have triggered aileron flutter, leading to the structural failure and subsequent separation of the left wing.