What happened
During cruise flight, the captain heard a loud pop and noticed an interruption on the electrical panel. The right "BUS OFF" and "GEN OFF BUS" warning lights illuminated immediately. No generator amperage or frequency readings were observed following the event. A faint odor of smoke was detected in the cabin.
The captain initiated the auxiliary power unit (APU) and transferred the right-side electrical load to the APU generator. The "BUS OFF" light extinguished, indicating temporary restoration of power. However, within a minute, the level of smoke increased significantly. The captain shut down the APU and requested the crew execute the electrical smoke and fire checklist.
An emergency landing was conducted. During the rollout, all four main gear tires failed simultaneously. The crew and passengers performed an emergency evacuation immediately after the aircraft came to a stop.
The investigation
Post-accident inspection of the aircraft revealed that the failure originated in the Generator Control Unit. Specifically, a capacitor installed within the unit's circuit had failed. This component failure caused the #2 Generator Control Unit to become inoperative.
The loss of the generator control unit resulted in the anti-skid system becoming inoperative. The lack of anti-skid functionality during the emergency landing directly contributed to the failure of all four main gear tires.