Since the crash landing of a Boeing 777 returning from Beijing to London’s Heathrow Airport on January 17, 2008, speculation and the rumor bill have looked for an explanation as to what caused a crash landing on a grassy area short of the runway after a seemingly normal flight. One persistent version blamed electromagnetic interference from the many WiFi systems in densely populated London. More recently, papers have noted that a cavalcade of cars brought Prime Minister Gordon Brown and a number of VIPs to Heathrow that morning for departure on an overseas flight. Could the electronics from the high end automobiles be the source of EMI? Now, a Special Report from the Air Accidents Investigation Branch (AAIB) seemingly rules out EMI and other popular theories. According to the report, “Extensive examination of the aircraft and detailed analysis of the recorded data have revealed no evidence of an aircraft or engine control system malfunction. There is no evidence of a wake vortex encounter, a bird strike, or core engine icing. There is no evidence of anomalous behavior of any of the aircraft or engine systems that suggests electromagnetic interference. The fuel has been tested extensively; it is of good quality, in many respects exceeding the appropriate specification, and shows no evidence of contamination or excessive water.” So what did cause the sudden non-response from the aircraft engines? The ongoing investigation will focus on the fuel system of both aircraft and the engines. Investigations are underway at Rolls-Royce, the manufacturer of the engines, and at Boeing, in Seattle, WA. The primary challenge at Boeing is to replicate the conditions the plane encountered as it flew over Siberia at an altitude of up to 40,000 feet and in temperatures as low as -76 degrees C. The investigation is ongoing. The interim Special Report is posted on the AAIB website.The shielding and testing of onboard instrumentation has long been recognized as critical factors. In your view, will EMC professionals find an expanding role in achieving aircraft safety? Post your thoughts at the Aerospace Community Forums.
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Interference Technology
Established in 1970, Interference Technology helps EMI/EMC engineers find solutions to their various testing, design, application and regulatory issues by publishing articles, news and other practical content. We help suppliers in these areas to find the right customers for their components, materials, test equipment and services through a wide range of marketing services, including lead generation, branding, market research and events. The publication is available in various printed and electronic media formats, with readers in over 60 countries. We also publish issues in local languages in China, Japan and Europe.