Aviation International News senior correspondent Ian Goold has been involved in aerospace since 1964 and in aviation media for more than 40 years. He enjoyed a 20-year career at Flight International magazine, where he was latterly air-transport editor before turning freelance in 1993. A winner of the European Regions Airline Association Hank McGonagle award for excellence in aerospace journalism and a Royal Aeronautical Society Aerospace Journalist of the Year global&nbsp;award, he has edited or contributed to aerospace and aviation magazines, special publications, and websites in Africa, Asia/Pacific, Europe, the Middle East, and North and South America. Ian entered aerospace as an apprentice at the British Aircraft Corporation at Brooklands (Weybridge), where he worked on production and final assembly lines of the Vickers Super VC10, and BAC One-Eleven , and manufacture of Concorde major sub-assemblies. He subsequently graduated from the BAC Design Training School to work in the airframe structures drawing office (including design of international future projects, such as the Panavia Tornado multi-role combat aircraft) before joining Flight International in 1973. Apart from years of reading aircraft magazines and books, his first direct contact with aviation media had come during the early 1970s when he was involved at Brooklands with the Weybridge Man-powered Aircraft Group, which designed and built the tenth aircraft to fly under purely human power. As an aviation journalist, he has worked at more than&nbsp; 50 of the major biennial&nbsp;global and regional international aerospace industry shows at Le Bourget, Farnborough, Singapore, and Dubai (having missed attending only one "Farnborough" since 1960), plus innumerable NBAA, HAI, (U.S.) AOPA, and EBACE Conventions and ERA Assemblies. His favourite aircraft is the Hawker Hunter, of which – as a schoolboy – he heard hundreds make their first flights from Dunsfold, where also on September 24, 2013, he saw the penultimate landing of the VC10 (happily involving an example of which he had witnessed the maiden takeoff in 1970) a day before the last example made the design's final flight (unless, of course....).

Senior correspondent

Ian Goold

British safety officials have issued recommendations for flight-data recorders (FDRs) to record engine fuel-metering information and for reviews of landing-gear failure requirements and Boeing 777 data buffering. Accident investigators call for the action among nine safety recommendations in the final report of the Jan. 17, 2008, British Airways Boeing 777-236ER accident at London Heathrow Airport, which was released on Tuesday.
Following a 10.5-hour flight from Beijing, the 777 (flying as British Airways Flight 38) lost power on its final approach to Heathrow, as both engines suffered an uncommanded “rollback” (or power reduction) at 720 feet an8d the airliner subsequently made a forced landing about 1,100 feet short of the runway. Ice in the fuel system had restricted fuel flow to the Rolls-Royce Trent 800 engines, according to the UK Department for Transport Aircraft Accidents Investigation Branch (AAIB). 
The airplane struck the ground at “a recorded normal peak load of 2.9 g, and a descent rate of about 1,400 fpm” and slid 1,220 feet. One main landing-gear sheared off the airplane on impact, while the other penetrated the upper surface of the wing. One passenger suffered a broken leg when landing-gear items entered the cabin; 34 passengers and 12 crew, among 151 remaining occupants, suffered minor injuries. 
The investigation determined that the fuel-flow restriction occurred at the fuel/oil heat exchanger (FOHE) on the right engine and “most likely” on the left-hand FOHE. Subsequent tests and data mining suggest the possibility of other restrictions was unlikely. The AAIB said ice can form from normal concentrations of dissolved and entrained water in the fuel, while the 777 was operating with low fuel flows over a long period. The FOHE was susceptible to restriction when presented with highly concentrated soft ice while fuel temperature was “below –10 degrees C [14 degrees F] and fuel flow above flight idle.” Relevant certification requirements did not accommodate this phenomenon as the risk had not been recognized previously.
At takeoff, the left main fuel tank temperature was –23 degrees C. Investigators said “a small percentage” of 777 flights take off with a fuel temperature below 0 degrees C. Fuel temperature reached a minimum of -34°C and minimum outside air temperature reached was -45°C, circumstances that were “unusual” but within the aircraft operating envelope. But the AAIB says the flight was unique among 175,000 flights in “having a low cruise fuel flow and a high fuel flow during approach while at a low fuel temperature.”
When fuel flow became restricted during final approach, both the left- and right-engine fuel-metering valves (FMVs) moved to full open and the electronic engine controls (EECs) entered loop-in control (LIC), with no effect on the fuel flow. “Data mining did not reveal any flight, other than the accident flight and [a later, November 2008 Delta Air Lines] flight, that had indicated an EEC LIC or had a genuine FMV position versus fuel flow mismatch.” 
The fuel temperature at the time of the engine rollback was -22 °C in both events, said investigators. When the crew attempted manually to increase thrust, there was no engine response. The digital flight-data recorders did not record FMV positions, and data buffering meant the information did not reach the quick-access recorder.
“Ice probably began to accumulate in the fuel feed pipes while the warm center tank fuel flowed through cold fuel pipes that pass through the main fuel tank at the start of the flight. During the later stages of approach, accumulated ice was probably released due to engine accelerations and possibly a combination of turbulence, aircraft pitch changes, and an increase in strut temperature,” concluded AAIB.
Following earlier recommendations, Boeing introduced changes to mitigate the risk from fuel icing in Trent 800-engine 777s. The EASA has approved a modified FOHE mandated from Rolls-Royce.

Final Accident Report Cites Boeing 777 Fuel Icing, Recommends Landing Gear Review

British safety officials have issued recommendations for flight-data recorders (FDRs) to record engine fuel-metering information and for reviews of landing

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