By Lindsay Hughes | December 16, 2013 Estimated reading time 2 minutes, 56 seconds.
The Transportation Safety Board of Canada (TSB) has concluded its investigation into the May 28, 2012, engine failure of a Boeing 777-333ER aircraft operated by Air Canada. The failure of the number 2 engine occurred during initial climb-out from Toronto’s Lester B. Pearson International Airport (Pearson) en route to Narita International Airport in Tokyo, Japan. The aircraft was airborne for 1 hour and 26 minutes before landing back at Pearson, carrying 16 crew members and 309 passengers.
Prior to its flight to Tokyo, the aircraft had arrived from Frankfurt, Germany. Toronto-based Air Canada staff completed a pre-flight inspection and reported no engine defects. A total of 1.5 litres of oil was added to the number 2 engine before the aircraft took off from Runway 23 at 14:25. The number 2 engine lost power at an altitude of 2,160 feet above sea level (ASL), while travelling at an airspeed of 206 knots; the crew received an engine indicating and crew alerting system (EICAS) engine fail warning approximately six seconds later. They then declared an emergency and notified air traffic control of the event.
According to the TSB, the crew followed the engine severe damage checklist in their Quick Reference Handbook, securing the engine by moving the thrust level to idle, the fuel control switch to cut-off, and pulling the engine fire switch. The aircraft was levelled off at 12,000 feet ASL, and the total fuel load was reduced by 86,600 kilograms in order to bring the aircraft down to its maximum approved landing weight.
Findings as to causes and contributing factors of the engine failure include the following:
- Eroded shroud cooling holes and a super-heated zone, which occurred over time due to a change to a higher-intensity laser. This change resulted in a variation in the shape and size of the shroud cooling holes, which resulted in the shroud integrity being reduced to the point of failure;
- Damage that had occurred to high-pressure turbine shrouds and hangers went undetected; and
- The number 2 engine lost power due to the failure of the high-pressure turbine stage 1 shroud.
The engine shut down did not result in any injuries; however, the underside of the aircraft’s right wing was damaged by engine debris ejected through the exhaust. Several vehicles on the ground were also damaged by falling debris.
To read the TSB’s full investigation report, click here.
