THE crash landing which happened at Heathrow Airport at the start of the year was most likely caused by a build up of ice in the fuel system.
Flight BA38 from Beijing to London landed safely but well short of the runway on January 17 after witnesses saw it struggling to clear the perimeter fence.
Due largely to the heroics of the pilot and co-pilot all 136 passengers and 16 crew members escaped without serious injury and an immediate investigation was launched.
The Air Accident Investigation Branch has been leading the enquiry ever since and has concluded the sudden loss of power was caused by ice in the engines - although it still has no idea how it managed to form.
Water is naturally present in aviation fuel and the investigators believe there may have been as much as five litres within the Boeing 777's fuel load. The AAIB report says the plane flew through unusually cold air over Siberia while en-route from Beijing to Heathrow.
The fuel temperature fell to -34C (-29F). But jet fuel should not freeze until it is at less than -57C (-70F), and the report says the temperatures involved were not unique.
In response the AAIB has made three recommendations to the Federal Aviation Administration and the European Aviation Safety Agency, which should be passed to Boeing and Rolls-Royce, makers of the engines.
It suggests immediate measures for the Boeing 777 to reduce the risk of ice forming, but also consider tests on all aircrafts of different engine type to ensure the same thing does not happen.
Finally, it recommends changes to the certification of aircraft and fuel systems to ensure they are tolerant to the build up and sudden release of ice in future.
In summary it said: "The accident flight was unique in that this has been the only recorded case of a restricted fuel flow affecting the engine performance to the extent of causing HP pump cavitation - the damage found within the pumps that alerted the investigators to the loss of fuel pressure.
"This is the first such event in 6.5 million flight hours and places the probability of the failure as being 'remote.'"
To see the report in full visit the Air Accidents Investigation Branch website by clicking here
