Air Transat Flight 236 was an Air Transat route between Toronto, Canada and Lisbon, Portugal flown by Captain Robert Piché and First Officer Dirk DeJager. On August 24, 2001, the flight ran out of fuel over the Atlantic Ocean with 306 people (293 passengers and 13 crew) aboard. The flight crew managed to successfully glide the plane, and safely landed in the Azores with no loss of life.[1]
Incident
Unknown to the pilots, the aircraft had developed a fuel leak in a fuel line to its right engine. During the course of the flight, the pilots had noticed a fuel imbalance between the fuel tanks in the left and right wings of the aircraft and had attempted to remedy this by opening a cross-feed valve between the tanks. This caused fuel from the operational tank to be wasted through the leak in the engine on the other side.
On the Airbus A330, as with most large modern passenger aircraft, an emergency ram air turbine is deployed automatically to provide essential power for sensors and instruments to fly the aircraft.
When the engines suffered a flame out, important systems became unavailable. Specifically, the aircraft lost its main hydraulic power which operates the flaps, brakes, and spoilers. Additionally, an aircraft without operating engines cannot use its thrust reversers to slow the plane after touchdown.
The pilots of the Airbus A330 were able to glide the aircraft to a landing at Lajes Air Base, Terceira Island in the Azores. The reported landing speed was about 200 knots (370 km/h) indicated airspeed (IAS), which is higher than the normal speed of 130 to 145 knots (240 to 269 km/h) IAS. There were no fatalities, but there were minor injuries. The favourable outcome was also due to the flight being rerouted on a more southerly route across the Atlantic to prevent congestion, bringing them closer to the Azores.
Sequence of events
At 04:38 UTC (estimated), a fuel leak started in the area of engine no. 2 (right engine).
At 05:16 UTC, a cockpit warning system chimed and told of low oil temperature and high oil pressure on engine no. 2. There is no obvious connection between an oil temperature or pressure problem and a fuel leak. At first, Captain Piché and co-pilot DeJager suspected these warnings were computer bugs and communicated with their Maintenance control center.
At 05:36 UTC, the pilots received a warning of fuel imbalance and diverted fuel from the port (left side) wing tanks to the starboard tanks, which were showing close to empty. Because the fuel leak in the starboard engine had still not been diagnosed, this diversion had the effect of sending fuel to the leak and causing further loss.
At 05:45 UTC, as it became clear that fuel was dangerously low, the crew decided to divert to Lajes Air Base in the Azores.
At 05:48 UTC, an emergency was declared with Santa Maria Oceanic air traffic control because of fuel shortage.
At 06:13 UTC, 28 minutes after the emergency declaration and 135 miles (217 km) from Lajes[3], engine no. 2 on the right wing flamed out, exhausted of jet fuel. Captain Piché then ordered full thrust from engine no. 1 on the left wing, and the plane descended to 33,000 feet (10,000 m), unable to stay at its 39,000 feet (12,000 m) cruising altitude with only one engine operating.
At 06:23 UTC, Mayday was declared with Santa Maria Oceanic air traffic control.
At 06:26 UTC, engine no. 1 flamed out at about 65 nautical miles (120 km) from Lajes Air Base[4].
Without engine power, control of the aircraft depended on the last backup, a ram air turbine, which supplied limited power to hydraulic and electrical systems. While Piché flew the plane, DeJager monitored its descent rate — around 2000 feet (600 metres) per minute — and calculated that the plane had about 15 to 20 minutes left before they had to ditch the plane in the water.
The crew flew the plane a few more minutes, until sighting the air base. Piché then had to execute a series of 360 degree turns to lose altitude. Although they successfully lined up with Runway 33, they faced a new danger. The plane was on a final descent, going faster than normal. Although they had unlocked the slats and deployed the landing gear, the airspeed was 200 knots (370 km/h), compared to the preferable 140 to 160 knots (260 to 300 km/h).
At 06:45 UTC, or 02:45 EST, after 19 minutes without engine power, the plane touched down hard 1,030 feet (310 m) down Runway 33 with about 200 knots (370 km/h). The aircraft bounced back into the air but touched down again 2,800 feet (850 m) from the approach end of the runway and came to a stop 7,600 feet (2,300 m) from the approach end of the 10,000 feet (3,000 m) runway. With the operation of the emergency brakes, several tires burst. Fourteen passengers and two crew members suffered minor injuries during the evacuation of the aircraft. Two passengers suffered serious, but not life-threatening injuries.
Investigation
The Portuguese Gabinete de Prevenção e Investigação de Acidentes com Aeronaves (GPIAA) investigated the incident along with Canadian and French authorities.[2]
The investigation revealed that the cause of the incident was a fuel leak in the number two engine, caused by an incorrect part installed in the hydraulics system by Air Transat maintenance staff. The part did not maintain adequate clearance between the hydraulic lines and the fuel line. This allowed vibration in the hydraulic lines to degrade the fuel line and cause the leak. Air Transat accepted responsibility for the incident and was fined 250,000 Canadian dollars by the Canadian government, which as of 2009 is still the largest fine in Canadian history.[2][update]
Although pilot error was listed as one of the lead causes for the incident, it was the skill of the pilots, and of the military Air Traffic Controller in service at the time, 1st Sgt. José Ramos,[5] that allowed the flight to land without fuel, causing only minor injuries to the passengers and minor damage to the airplane, which is still in service. The pilots returned to a heroes’ welcome from the Québec press.