Air France Flight 296
Encyclopedia
Air France Flight 296 was a chartered flight of a new fly-by-wire
Fly-by-wire
Fly-by-wire is a system that replaces the conventional manual flight controls of an aircraft with an electronic interface. The movements of flight controls are converted to electronic signals transmitted by wires , and flight control computers determine how to move the actuators at each control...

 Airbus A320-111 operated by Air France
Air France
Air France , stylised as AIRFRANCE, is the French flag carrier headquartered in Tremblay-en-France, , and is one of the world's largest airlines. It is a subsidiary of the Air France-KLM Group and a founding member of the SkyTeam global airline alliance...

. On June 26, 1988, it was flying over Mulhouse-Habsheim Airport
Mulhouse-Habsheim Airport
Mulhouse-Habsheim Airport is a small airport near the town of Habsheim in France. The airport is a former military base, and is now mainly used for light aircraft...

 (ICAO code LFGB) as part of an air show. The low-speed fly-by was supposed to take place at with landing gear down at an altitude of 100 feet. Instead, the plane slowly descended to 30 feet and crashed into the tops of trees beyond the runway. Three passengers died. This was the first crash of an Airbus A320
Airbus A320
The Airbus A320 family is a family of short- to medium-range, narrow-body, commercial passenger jet airliners manufactured by Airbus Industrie.Airbus was originally a consortium of European aerospace companies, and is now fully owned by EADS. Airbus's name has been Airbus SAS since 2001...

. The cause of the accident is disputed, as many irregularities were later revealed by the accident investigation.

Official report

The official report states the causes of the accident were:
  • Very low flyover height, lower than surrounding obstacles.
  • Very low speed, slowing down to reach maximum possible angle of attack
    Angle of attack
    Angle of attack is a term used in fluid dynamics to describe the angle between a reference line on a lifting body and the vector representing the relative motion between the lifting body and the fluid through which it is moving...

    .
  • Engines at minimum idle flight power.
  • Late application of go-around power.


This combination led to the impact of the aircraft with the trees.

The Commission assumed that if the descent below 100 feet was not deliberate, it may have resulted from failure to take proper account of the visual and aural information intended to give the height of the aircraft.

A320 operation anomalies

Third-party investigations into the crash dispute the official findings. Captain Michel Asseline asserted that the altimeter read 30m (100'). However, while the pilots were trained in metric, this particular plane was in Imperial units. Air France didn't inform the crew of this critical change (yet the crew voices are recorded on black boxes, and they use imperial units). Captain Asseline also reported that the engines didn't respond to his throttle input as he attempted to increase power. In the month prior to the accident, Airbus
Airbus
Airbus SAS is an aircraft manufacturing subsidiary of EADS, a European aerospace company. Based in Blagnac, France, surburb of Toulouse, and with significant activity across Europe, the company produces around half of the world's jet airliners....

 had posted two Operational Engineering Bulletins (OEBs) indicating possibilities of anomalous behavior in the A320 aircraft. These bulletins were received by Air France, but were not sent out to pilots until after the accident:

OEB 19/1: Engine Acceleration Deficiency at Low Altitude

This OEB noted that the engines may not respond to throttle input at low altitude.

OEB 06/2: Baro-Setting Cross Check

This OEB stated that the barometric altitude indication on the A320 did not always function properly.

Captain Michel Asseline used those bulletins to assert that these 2 malfunctions happened and caused both the lack of power when the throttle was increased, and the inability of the crew to recognize the sharp sink rate as the plane passed 100 feet into the trees.

In fact none of those bulletins apply to the case. Moreover there is much evidence that engine power increased correctly and the airplane gave correct altitude.

First of all Captain Asseline was confident that there had been a malfunction in the engines and he was eager to cooperate with investigators.

Indeed the engines did not give strong power in 1 or 2 seconds as usual. This comes from the a pilot error of setting the engines at minimum idle flight. In this case regulations state that engines may take 5s to increase from complete idle to good power (80% of continuous max). The lack of power was increased with the slowing down and the extremely low speed, such a way that the tail was lower than the undercarriage. It can be pointed out that those conditions never happen during a landing, that is why pilots have been baffled with airplane poor reactions.

On the other hand the power of engines has been recorded on black boxes, and is correct. The engine sound has been recorded also, even on amateur videos. The frequency analysis indicates the same increasing power.

Stating that the engine power had been carelessly set too low and go around too late, the investigators bent over the infringement on flight plan altitude.
Regulations state that the airplane should stay 170 feet above ground. For the special occasion of this show, the flight plan authorized a lower flight of 100 ft. The clear violation of this altitude was a big concern for pilots during coming trial, not ignoring that it was a major cause of crash. Thus Captain Asseline made all possible objections against this violation.
  • Firstly he stated that he respected the altitude. Yet the videos show that altitude was 30ft and data recorders indicate the same.
  • He stated that the indication in cockpit was wrong, even if indications on data recorder were correct. Yet the airplane pronounced the height in cockpit like any alarm or warning: 200ft, 100ft, then 50ft, 40ft, 30ft... They are recorded on black box.
  • He stated that he did not hear these height warnings, because he wore a helmet. Thus he may not have heard these warnings (and thus any other warning or alarm, they sound in cockpit and not always in helmet).
  • For further critics on investigation Captain Asseline asserts that black boxes have been tampered.
  • The flight data recorder and the cockpit voice recorder are 4 seconds out of synchronization during the last part of the recording.
  • To go further he tried to have the black boxes regarded as irrelevant during his trial. Indeed they were taken out of airplane by French aeronautics authorities (DGAC) and Airbus, the manufacturer of the airplane is also French. The criminal investigators that pursue on a trial took back these boxes and sealed them only 10 days after DGAC. Moreover he had a Swiss professor to demonstrate that the black boxes on trial were not the one out of the crash. It was to be demonstrated thanks to a rough photo (150ft away) of the boxes carried away of the crash.
  • Coming back to basic piloting, it must be reminded that the final phase of landing is achieved thanks to direct view. Regulations state it is mandatory for nearly all landings. It means that pilots closing ground have to take account of visual indications and they must not refer to instruments. Captain Asseline asserts that he focused on altimeter before reaching 30ft, and then his first officer reacted.

Captain Asseline made numerous interviews on media to advocate his case with these arguments and others. His allegations were often repeated.

Outcome

The accident and resulting fire killed 3 of the 130 passengers. Of those three, one was an adult and the other two were young children. It is believed that the adult, a female, had attempted to rescue a trapped 7 year old girl. During the evacuation, people had pushed on the back of the girl's seat, and the seat folded over on the girl who became trapped by her own seat belt. The woman had attempted to free the young girl from her seat, and both died of smoke inhalation. The second child, a male, was found impaled through the chest by a piece of wreckage.

Captain Asseline, First Officer Mazière, two Air France officials and the president of the flying club sponsoring the air show were all charged with involuntary manslaughter. All 5 were found guilty. Captain Asseline was initially sentenced to 6 months in prison along with 12 months of probation. The others were sentenced to probation. During the appeal process, Captain Asseline's sentence was increased to 10 months of imprisonment along with 10 months of probation. Asseline walked free from the court and said he would appeal to France's Supreme Court, the Cour de Cassation. According to French law, Asseline was required to submit himself to the prison system before his case could be taken up by the Supreme Court.

Dramatization

On 8 March 2010, an episode of the Mayday
Mayday (TV series)
Mayday, also known as Air Crash Investigation in the United Kingdom, Australia and Asia and Air Emergency and Air Disasters in the United States, is a Canadian documentary television programme produced by Cineflix investigating air crashes, near-crashes and other disasters...

(Air Crash Investigation, Air Emergency) TV series featuring this accident was broadcast. The episode is entitled "Pilot vs. Plane".

See also

  • List of accidents and incidents involving commercial aircraft
  • List of airshow accidents and incidents
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