Beech 65 near Sidney, NE — 2019-07-09
- Date
- 2019-07-09
- Location
- Sidney, NE, USA
- Airport
- KSNY
- Aircraft
- Beech 65
- Registration
- N62069
- Category
- Airplane
- Highest injury
- None
- Fatalities
- 0
- Phase of flight
- Takeoff roll
Probable cause
The improper maintenance of the outboard left wing, which allowed electrical arcing and leaking of the fuel sending unit and subsequently resulted in ignition of fuel vapors and an explosion of the outboard left wing.
NTSB narrative
The pilot had topped off the outboard fuel tanks before departure. While taxiing for takeoff, the stall warning horn activated, and the pilot pulled the circuit breaker to disable the horn. During the takeoff roll, the pilot heard a loud bang, observed significant damage to the outboard left wing, and aborted the takeoff. While taxiing back to the ramp, the pilot noted smoke coming from the top of the left wing. The pilot taxied the airplane to the corner of the ramp, performed an abbreviated shutdown, grabbed a fire extinguisher, and evacuated. The pilot did not observe any additional smoke or fire and did not discharge the fire extinguisher. Examination of the airplane revealed fire and thermal damage near the wing root area, including melted and burned wiring. Due to some loose installation screws, a fuel leak was found coming from the fuel sending unit, which had recently been replaced. In addition, a wiring harness was found pinched between a metal clamp and a wing rib. Metal-to-metal contact was noted between exposed wiring and the wing rib. Based on the fuel leak in the left wing and the pinched wiring, it is likely fuel vapors ignited and caused an explosion of the outboard left wing. A few months before the accident, the outboard left wing was replaced. The operator's director of maintenance stated that the electrical wiring in the wing was not inspected during the wing replacement.
Analysis
- Primary failure mode
- Mechanical failure
- First missed decision gate
- Pilot should have investigated stall warning horn before takeoff.
NTSB coding
Evidence available
- 4 docket documents