British Airways Flight 5390

A BAC 1-11 British Airways

On June 10, 1990, there came by a maintenance error to an incident on the British Airways flight 5390th A BAC 1-11 with the registration G - BJRT and the proper name " County of South Glamorgan " lost during the flight from Birmingham Airport to Málaga at 07:33 UTC a cockpit window. This resulted in a pressure drop at which the co-pilot and the cabin crew were able, however, prevent people suffered serious damage.

Circumstances of the accident

The Flight 5390 British Airways started 60 minutes late from Birmingham Airport with the aim of Málaga. When the aircraft reached an altitude of 17,300 ft in the climb (about 5,300 m) at a speed of 300 knots ( 556 km / h ), the left cockpit window of the anchor was pulled outward. Captain Tim Lancaster, who had just taken off, was drawn by the suction half out of the window. With his feet, he got caught in the steering column, which prevented him has been completely sucked out of the plane. Through the steering column movement, the plane tilted by 6 ° down and turned 25 ° to the right.

Flight attendant Nigel Ogden, who had just left the cockpit, had heard a bang and noticed the clouds of mist that filled the cabin and pointed to a sudden loss of pressure. He returned at once, gave Lancaster fixed at the hip and so secured the captain.

The cockpit door was torn and was partially over the control. Through the draft numerous items were drawn away and sucked out the window, including an oxygen tank along with their anchor.

Copilot Alastair Atchison was still strapped in and had first problems controlling the aircraft, as Lancaster's legs as well as remains of the cockpit door blocked the left control column. Atchison then initiated a descent to reach a height with enough oxygen. His oxygen mask he put deliberately not to continue to talk with the crew can.

Meanwhile, the cabin chief John Heward had also come into the cockpit, secured to the strap of the Jump Seats, held his hand firmly and Ogden could secure it with the strap of the pilot. Even with the aid of the third flight attendant, Simon Rogers, it was not possible for them to move into the Lancaster cockpit again against the wind pressure.

Atchison had now dropped and reported to decline due to pressure loss at 10,000 ft ( 3,000 m) an emergency call. He also reduced the speed to 150 knots (278 km / h). Due to the noise in the cockpit Atchison could understand the response of air traffic controllers in London just bad. The air traffic controller took the emergency call specifically counter, but was waiting for more information from the pilots and now worked normally. There was, however this does not cause problems, except that the competent authorities were informed late.

Atchison was directed by radio to the nearest airport to Southampton. He succeeded to the machine at 7:55 clock land safely without the assistance of a second pilot in the cockpit. During the entire time Lancaster hung about two-thirds from the cockpit window. Still on the runway up the passengers from the stairs, while rescue teams rescued the captain.

Contrary to initial fears Lancaster had survived and came back to consciousness after landing. He wore them broken bones, bruises and frostbite. The steward Nigel Ogden suffered in securing the aircraft captain, a dislocated shoulder and frostbite in the face area. In 2001, Ogden finally had to give up his job as a result of post-traumatic stress disorder.

The Lost window was later found near Cholsey, Oxfordshire.

Cause of the accident

The falling out of the cockpit glazing can be explained with a chain of carelessness and errors during maintenance. The flight was the first of this aircraft after maintenance in the hangar while the was replaced due to a defect report describes the left cockpit window. This work was carried out in the early hours of the previous day. Since the film was just busy, the shift manager took over this work itself

Contrary to the rules, the left cockpit window was not previously fixed with 90 countersunk screws of type A211 - 8D, but with the shorter by 2.5 mm variant A211 - 7D. Since the last window replacement was behind only four years, it obviously had not led to impairments.

The shift supervisor removed the window with the help of a colleague. Since some screws were damaged in the process and showed other signs of rust, he decided to get new screws from the spare parts store. Screws of this size bear no label and the shift manager did not bother to identify the correct prescribed part number, but contented himself with one of the old bolts as a pattern.

The employee in the parts store made ​​the shift manager still points out that the correct size is not 7D, 8D but was, however, the shift supervisor was not on one because he had just removed screws of type 7D.

Since not enough screws of size 7D were available in this stock of spare parts, the shift supervisor went to a different camp on the airport, which was not occupied at this time. There he took more screws, which he held for 7D, but in reality were 8C. This, however, had the same length as the prescribed 8D, the diameter was about 0.7 mm less. He also participated with six screws of size 9D, because he was of the opinion that the corner screws would have to be longer.

The service manual was for the screws to a torque of 15 lbf in ( about 24 Nm), the shift supervisor, however, decided the bolts to 20 lbf in attracting. A calibrated torque wrench was not available, so he used a torque screwdriver.

Through an awkward position its mobile platform and the fact that he had to use both hands, he had no direct view of the screws. He used 84 of the new bolts. When he came to the six corner screws, he noticed that he was wrong, and the measure it screws did not fit the type 9D. Here he used the old bolts. The shift supervisor did not notice that the countersunk heads of the new bolts were lower than in the old.

A review of the work took place only by the fact that the function of the window heater was tested. Since the work was done by the shift supervisor yourself, there was no one who checked his work in the same night. A review by a second person was not prescribed because the replacement of a cockpit window was not considered a critical action.

The following night, before the aircraft takes off, replaced the shift manager on another machine also consists of a cockpit window. Although he realized that this was not fixed with 7D - 8D but with screws, but the difference did for a modification of the series over the years, and measured the no importance.

With most commercial aircraft cockpit discs are installed from the inside outwards so that it presses the higher internal pressure in the cockpit their sockets. In the BAC 1-11, however, the disks are inserted and screwed from the outside inwards from the outside. The force necessary for compression of the seals and by the pressure difference is applied only by the screw. Therefore, the glazing can be pushed and pulled at the failure of the screws to the outside.

Immediate action by British Airways

When first it was announced that screws were used with insufficient length, put British Airways an extraordinary examination of all BAC 1-11 before the next start. Each fourth screw of the cockpit window should be removed and measured. Here at several planes wrong screws were found.

When in the course of further investigation also became known that in the incident found some screws with a small diameter to use, this led to a second investigation of all aircraft. Here was enough for a visual inspection, which was performed in all screws. In none of the investigated aircraft were discovered, however, too thin screws.

The accident in the media

The accident of British Airways Flight 5390 was in the Canadian television series Mayday - Alarm shown in the cockpit with the English title Blow Out and the German title Horror Flight 111. In re-enactments, animation and interviews with participants and investigators was reported on the preparations, the process and the backgrounds of the flight.