Air Transat Flight 236

Air Transat Flight 236 was an Air Transat route between Toronto and Lisbon 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 + 13 crew) aboard. The flight crew was able to successfully land the plane in the Azores with no loss of life. ^[1]

Incident

Picture of an Air Transat Airbus A330 similar to C-GITS

Unknown to the pilots, the aircraft had developed a fuel leak in 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 only caused fuel from the operational tank to be wasted through the leak in the engine on the other side.

Without fuel, an aircraft's engines cannot provide thrust or electrical power. As the Airbus is a fully fly by wire design, without operating engines the plane is dependent on the emergency ram air turbine to fly the aircraft.

When the engines flamed 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 indicated airspeed, higher than the normal speed of 130 to 145KIAS. There were no fatalities, but there were minor injuries. The favorable outcome was also due to the flight being rerouted on a more southerly route across the Atlantic due to congestion, bringing them closer to the Azores.

Sequence of events

Flight TS 236 took off from Toronto at 8.52 p.m. (EDT) on Thursday August 23 2001. It made an emergency landing at 6:45 a.m. (UTC) on August 24 2001, at Lajes Airport, Terceira, Azores, Portugal.

There were 293 passengers and thirteen crew members onboard. The aircraft was an Airbus A330 manufactured in 1999, configured with 362 seats and placed in service by Air Transat in April 1999. Leaving the gate in Toronto, the aircraft had 47.9 tonnes of fuel on board, 5.5 tonnes more than required by regulations.

At 05:36 UTC, approximately four hours into the flight, a fuel leak started, and cockpit warning systems chimed and told of an oil pressure problem on one side of the aircraft. At first, Captain Piché and co-pilot DeJager suspected these warnings were computer bugs, but as the warnings persisted, the crew decided to divert to Lajes Air Base in the Azores.

At 06:13 UTC, 28 minutes after the emergency declaration, 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 30,000 feet (9,150 metres), unable to stay at cruising altitude with one engine. Thirteen minutes later, engine no. 1 flamed out. In just under a quarter of an hour after declaring a fuel emergency, Flight 236 had become a giant glider.

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. Whilst 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 swerving maneuvers to lose altitude and slow the plane. Although they successfully lined up with Runway 15/33, 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, compared to the preferable 130-140 knots.

At 06:46 UTC, or 02:46 EDT, 20 minutes after the engine failure, the plane touched down on Runway 15/33 at about 370 km/h. With the operation of the emergency brakes, several tires burst. The plane eventually stopped in the middle of the runway. Sixteen passengers and two crew members were injured during the evacuation of the aircraft. Most injuries were minor or very minor. Two passengers suffered serious, but not life-threatening, injuries.

Investigation

The investigation revealed that the cause of the accident 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. It was discovered that the technician who worked on the engine had reported to his supervisor/manager that there was a problem with the part and that it did not fit properly. The supervisor/manager insisted that the (incorrect/incomplete) part be used rather than wait for a new proper part to arrive. Air Transat accepted responsibility for the incident and was fined CAN$250,000 by the Canadian government, which as of 2007 is still the largest fine in Canadian history as stated on Discovery Channel ^{[citation needed]}.

Although pilot error was listed as one of the lead causes for the incident, it was the skill of the pilots which 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 in the Québec press.

The incident also led to the Direction Générale de l'Aviation Civile (DGAC) and FAA issuing an Airworthiness Directive,^[2] forcing all operators of Airbus Model A318-100, A319-100, A320-200, A321-100, and A321-200 Series Airplanes; and Model A320-111 Airplanes to change the flight manual, stressing that crews should check that any fuel imbalance is not caused by a fuel leak before opening the cross-feed valve. The French Airworthiness Directive required all airlines operating these Airbus models to make revisions to the Flight Manual before any further flights were allowed. The FAA gave a 15 day grace period before enforcing the AD.

Dramatization

A documentary in the Air Crash Investigation series (also known as Mayday and as Air Emergency) was made about this incident. The episode's name is "Flying on Empty" and it was aired on the Discovery Channel and the National Geographic Channel.

MSNBC also produced a report on the incident, entitled "A Wing and A Prayer."

See also

• Gimli Glider, involving a 1983 emergency landing of an Air Canada Boeing 767-200 without fuel.
• Hapag-Lloyd Flight 3378, involving a 2000 emergency landing without fuel.
• British Airways Flight 9 in which a volcano's dust turned a Boeing 747 into the world's largest glider.

References

External links

• Accident Investigation Final Report from the Portuguese Aviation Accidents Prevention and Investigation Department (PDF)
• Air Transat's report
• Accident description on the Aviation Safety Network
• News report on logistical issues after the incident
• CBC News article
• Captain Robert Piche's Official Website

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