British Airways Flight 38

British Airways Flight 38 was a scheduled international passenger flight operating the flight from Beijing Capital International Airport in Beijing, China, to Heathrow Airport in London, United Kingdom, an 8,100-kilometre (4,400 nmi; 5,000 mi) trip. On 17 January 2008, the Boeing 777-200ER aircraft, which crash-landed short of the runway at Heathrow, touched down hard on the grass undershoot, breaking off the landing gear and skidding across the turf infield before sliding to the right of the threshold, 330 metres from its initial impact point. Of the 152 people on board, no fatalities resulted, but 47 people were injured, 1 of them seriously. The extensively crippled aircraft (registered as G-YMMM), which sustained heavy damage to both engines, both wing roots, wing-to-body fairing, flaps, right-hand horizontal stabilizer's leading edge, fuel tanks (which were punctured by the gear breaking off) as well as the lower fuselage belly from the ground slide, was written off as a result, becoming the first hull loss of a Boeing 777.

The accident was investigated by the Air Accidents Investigation Branch (AAIB) and their final report was issued in February of 2010. Ice crystals in the jet fuel were blamed as the cause of the accident, clogging the fuel/oil heat exchanger (FOHE) of each engine. This restricted fuel flow to the engines when thrust was demanded during the final approach to Heathrow. The AAIB identified this rare problem as specific to Rolls-Royce Trent 800 engine FOHEs. Rolls-Royce developed a modification to the FOHE; the European Aviation Safety Agency (EASA) mandated all affected aircraft to be fitted with the modification before 1 January 2011. The US Federal Aviation Administration noted a similar incident occurring on an Airbus A330 fitted with Rolls-Royce Trent 700 engines and ordered an airworthiness directive to be issued, mandating the redesign of the FOHE in Rolls-Royce Trent 500, 700, and 800 engines.