Contrasting Outcomes in Multiteam Systems – Part 2

Airbus 340

Air France Flight 358 – 02 August 2005 [2]

What Happened?

It was an Airbus A340-313, which departed Paris, France on a scheduled flight to Toronto, Ontario, Canada with 297 passengers and 12 crew members on board. Thunderstorms were forecasted at Toronto prior to its departure, and while approaching, the crew was advised of weather-related delays. On final approach, they were advised that the crew of an aircraft landing ahead of them had reported poor braking action. Flight 358’s aircraft weather radar displayed heavy precipitation encroaching on the runway from the northwest.

At about 200 feet above the runway threshold, while on the instrument landing system approach to the runway with autopilot and auto-thrust disconnected, the aircraft deviated above the glide slope and the groundspeed began to increase. The aircraft crossed the runway threshold above the glide slope. During flare, the aircraft travelled through an area of heavy rain, and visual contact with the runway environment was significantly reduced. There were numerous lightning strikes particularly at the far end of the runway. The aircraft touched down about 3800 feet down the runway, but was not able to stop on the 9000 feet runway and departed the far end, coming to standstill in a ravine at 2002 UTC (1602 Eastern Daylight Time). It caught fire.

All passengers and crew members were able to evacuate the aircraft before the fire reached the escape routes. However 2 crew members and 10 passengers sustained serious injuries during the crash and the ensuing evacuation.

Aftermath of Air France Flight 358

How it Happened?

The crew conducted an approach and landing in the midst of a severe and rapidly changing thunderstorm. After the autopilot and autothrust systems were disengaged, the pilot flying increased the thrust in reaction to a decrease in the airspeed and a perception that the aircraft was sinking (likely pitch down illusion!). This made the aircraft deviate above the glide path. At about 300 feet above ground level, the surface wind began to shift from a headwind component to a 10-knot tailwind component, increasing the aircraft’s groundspeed and effectively changing the flight path. The aircraft crossed the runway threshold about 40 feet above the normal threshold crossing height. Approaching the threshold, the aircraft entered an intense downpour, and the forward visibility became severely reduced. When the aircraft was near the threshold, the crew members became committed to the landing and believed their go-around option no longer existed.

The touchdown was long because the aircraft floated due to its excess speed over the threshold and because the intense rain and lightning made visual contact with the runway very difficult. The aircraft touched down about 3800 feet from the threshold of Runway 24L, which left about 5100 feet of runway available to stop. The aircraft overran the end of runway at about 80 knots and was destroyed by fire when it entered the ravine. Although the area up to 150 m beyond the runway was compliant with Aerodrome Standards and Recommended Practices, the topography of the terrain beyond this point, along the extended runway centreline, contributed to aircraft damage and to the injuries to crew and passengers. The downpour diluted the firefighting foam agent and reduced its efficiency in dousing the fuel-fed fire, which eventually destroyed most of the aircraft.

Cause of the Accident & The miracle, All survived!

Besides the weather playing spoilsport, the likely reason for fire after landing was that the integrity of the fuel tanks was compromised while the aircraft was slowing down. Once the fuel started leaking, it was likely that the inboard engines or sparks from metal to metal contact could have ignited the fuel; or the hydraulic fluid leaking from the landing gear might have provided the initial fuel and the overheated brakes, the ignition source. There was no significant fire before the aircraft reached the ravine, only when the aircraft stopped, the fire intensified. The leaking and pooling fuel provided an abundant supply to feed the fire. The intensity of the fire grew while the evacuation was in progress, and shortly after completion of the evacuation, the fuselage was engulfed in flames. The cabin furnishing, carry-on luggage, and cargo hold contents sustained the fire. The dilution of the firefighting foam agent by the heavy downpour reduced its efficiency in dousing the fire.

In hindsight, What was the Role of Shared Leadership?

The evacuation was successful due to the training and actions of the whole cabin crew. The performance of the cabin crew was exemplary and professional, which indeed was a significant factor in successful evacuation of all on board. There was effective communication between the cockpit crew and the cabin crew. Because the cabin crew were advised of the possibility of a missed approach, they were in a state of heightened awareness during the landing phase and were, therefore, prepared to respond immediately in the event of an emergency. The availability of three supplemental cabin crew members onboard contributed to the success of the evacuation – two of them were in command of passenger evacuations at emergency exits and the third played a pivotal role in opening an emergency exit and subsequently assisted passengers at the foot of the R4 slide. 

Continues…

Read More

Air Canada Flight 797

Shared Leadership in Multiteam Systems

Bienefeld & Grote’s Study on Multiteam Systems

Lessons from the Study on Multiteam Systems

Reference

Acknowledgement Image courtesy Wikimedia Commons