What happened
While performing a takeoff roll, the aircraft began veering toward the right shortly after the pilot disengaged the nose gear steering. During this maneuver, the co-pilot observed fluctuations in engine performance indicators and initiated an aborted takeoff. In an attempt to stabilize the aircraft, the pilot applied left rudder and braking to correct the rightward drift. However, the aircraft swung right once more before eventually turning sharply to the left. This resulted in the aircraft type departing the left side of the runway in a tail-first motion. The incident resulted in substantial damage to the airframe, which had recorded a total of 18,040.3 flight hours.
Findings
Investigations into the mechanical failure focused on the left engine's wiring harness. Technicians discovered that the outer shielding on the electronic fuel computer harness assembly was degraded, with a 3-inch section missing and various areas showing significant chafing. The ground wire for this shielding had worn through, leaving the internal wiring exposed. Further testing of the connection to the fuel computer revealed an intermittent electrical failure. Upon inspecting the connector, investigators found that the wire at the pin's crimp location had broken off. Microscopic examination of the pin interior revealed broken wire fragments that showed signs of corrosion. Simulations confirmed that this intermittent electrical connection caused N1 spool fluctuations of 2,000 rpm during engine testing. Although maintenance records indicated that the wiring had been inspected only six days prior to the event, the degradation of the harness components had gone undetected.