Britannia Airways Flight BY226A

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**Britannia Airways Flight BY226A**
Summary
A Britannia Airways Boeing 757-200 similar to G-BYAG
Date	14 September 1999
Type	Destabilised approach
Site	Girona, Spain
Passengers	236
Crew	9
Injuries	44
Fatalities	0
Survivors	245 (all)
Aircraft type	Boeing 757-204
Operator	Britannia Airways
Tail number	G-BYAG

Britannia Airways Flight BY226A was an international charter flight from Cardiff, Wales, UK, which crashed on landing at Girona Airport, Spain on 14 September 1999, and broke apart. Of the 236 passengers and 9 crew on board, there were no fatalities, but two were seriously injured and 42 sustained minor injuries. The Boeing 757-204 aircraft, registration G-BYAG, was damaged beyond economic repair and scrapped.

1 Flight history
2 Accident sequence
3 Post crash
4 Investigation and final report
5 References
6 External Link
7 Sources

[edit] Flight history

The holiday charter flight was landing at night, through thunderstorms with heavy rain at 21:47 UTC (23:47 local). Several preceding flights had diverted to Barcelona and this was planned as BY226A's alternate. The weather prior to the landing approach was reported as:

Surface wind 350/6 kt, visibility 4 km, thunderstorm with heavy rain, cloud 3-4 octas at 1,500 feet, 1-2 octas cumulonimbus at 3,000 feet, 5-7 octas at 4,000 feet, temperature 20°C/ dewpoint 20°C, QNH 1010 mb, remarks recent rain.

[edit] Accident sequence

The crew initially executed the VOR/DME non-precision instrument approach procedure to runway 02. Upon becoming visual, the crew determined that the aircraft was not adequately aligned with the runway and initiated a missed approach. A change in wind direction now favoured the opposite runway, so the aircraft was positioned for an ILS (Instrument Landing System) approach to runway 20. The aircraft descended below cloud and became visual with the runway at around 500 feet above ground level. At a late stage in the final approach, the airfield lighting failed for a few seconds.^[1] The aircraft touched down hard, bounced, and made a second heavier touchdown causing substantial damage to the nosewheel and its supports. This caused further damage to the aircraft systems, including loss of electrical power, interference with controls and an uncommanded increase in thrust.

The Boeing left the runway at high speed, approximately 1,000m from the second touchdown point. It then ran 343m across flat grassland beside the runway, before going diagonally over a substantial earth mound adjacent to the airport boundary, becoming semi airborne as a result. Beyond the mound it hit a number of medium sized trees and the right engine struck the boundary fence. The aircraft then passed through the fence, re-landed in a field and both main landing gears collapsed. It finally stopped after a 244m slide across the field, 1,900m from the second touchdown.

Damage was substantial: the fuselage was fractured in two places and the landing gear and both engines detached. Despite considerable damage to the cabin, the crew evacuated the aircraft efficiently. However, 3 of the 8 emergency exits couldn't be opened and several escape slides did not inflate (though with the fuselage sitting on the ground this was not a great problem).

The tower controller, aware shortly after touchdown that something was amiss, activated the emergency alarm. However, the emergency bell did not ring. Fire crews were alerted by a dedicated telephone line and went to the threshold of runway 20 and drove along the runway looking for the aircraft, without success. The search spread to the sides of the runway and the overshoot area. The wreckage was eventually located 18 minutes after the accident. There was a further 14 minutes delay while the fire crews tried to gain access to the site. In all, transfer of passengers to the terminal building was not completed for one hour ten minutes.

[edit] Post crash

Remarkably, there were no immediate fatalities and the injuries were few: 2 serious and 42 minor. However, one passenger, who had been admitted to hospital with apparently minor injuries and discharged the following day, died five days later from unsuspected internal injuries.

Airport authorities were criticised after the accident, particularly for the fact it took rescue crews more than an hour to reach and evacuate the scene. Indeed, at least one passenger actually walked across the airfield to the terminal to seek help.^[2]^[3]

[edit] Investigation and final report

The accident was investigated by the Spanish Comisión de Investigación de Accidentes e Incidentes de Aviación Civil (CIAIAC). In its final report, the CIAIAC's finding was:^[4]

"It is considered that the most probable cause of the accident was the destabilisation of the approach below decision height with loss of external visual references and automatic height callouts immediately before landing, resulting in touchdown with excessive descent rate in a nose down attitude. The resulting displacement of the nose landing gear support structure caused disruption to aircraft systems that led to uncommanded forward thrust increase and other effects that severely aggravated the consequences of the initial event."

The following contributing factors were also determined:

"1. Impairment of the runway visual environment as a result of darkness and torrential rain and the extinguishing of runway lights immediately before landing.

2. Suppression of some automatic height callouts by the GPWS «SINK RATE» audio caution.

3. The effect of shock or mental incapacitation on the PF (Pilot Flying) at the failure of the runway lights which may have inhibited him from making a decision to go-around.

4. The absence of specific flight crew training in flight simulators to initiate a go-around when below landing decision height.

5. Insufficient evaluation of the weather conditions, particularly the movement and severity of the storm affecting the destination airport."

[edit] References

^ Subsequent tests estimated the lighting outage at approx. 11 seconds in duration.
^ "Special Bulletin S1/2000 - Boeing 757-204, G-BYAG", Air Accidents Investigation Branch, 2000. Retrieved on 2006-09-27.
^ "BBC report of air crash", BBC, 1999. Retrieved on 1999-09-15.
^ ASN Accident Record.