Siai-Marchetti SF260 N16FD accident near Fullerton, California

Probable cause

The failure of the pilot to set the flaps to the proper takeoff setting before takeoff, resulting in an aerodynamic stall during takeoff and loss of control.

NTSB analysis

An aerobatic training flight was flown by an airline transport pilot. The preflight, taxi, and initial takeoff roll were uneventful until just after rotation, when the airplane began rolling left. The pilot attempted to correct for the roll to the left by adding full right aileron and rudder, but the airplane continued to roll to the left and impacted the ground off the left side of the runway. After the airplane impacted the ground, it continued to travel across a flight school ramp, striking four airplanes, and impacting a hangar, resulting in substantial damage to the fuselage. A small postaccident fire ensued.

Postaccident examination of the airplane and engine revealed no anomalies that would have precluded normal operation.

A review of onboard video revealed that, as the airplane was taxiing to the runway hold line, the left flap was in the neutral (or retracted) position. Furthermore, the pilot and the passenger discussed the takeoff, but make no mention of the flap position before takeoff.

The airplane operations manual and the Before Take-off checklist state that the takeoff flap setting was 20. However, video evidence shows that the pilot failed to set the flaps to the takeoff setting before takeoff which would have resulted in decreased lift, and an increased stall speed. The pilot was likely unaware of the flap setting as the airplane aerodynamic stalled and the pilot was not able to maintain airplane control.

Airport surveillance video depict the airplane on the runway and accelerating. About 3 seconds later, the nose gear and left main gear were clear of the runway, and the airplane banked slightly to the right. About 2 seconds after that, the airplane was airborne and pitched up slightly and was rolling to the left; 1 second later, the left bank increased to about 15° consistent with the airplane at or near an aerodynamic stall.

Text from the NTSB. Open the NTSB docket for WPR16LA167 for the full record.