Wednesday, August 20, 2014

US aviation agency grounds Air India Dreamliner

NEW DELHI: The US Federal Aviation Administration (FAA) on Wednesday grounded an Air India Dreamliner in Seoul to examine its engines. The American regulator's move came after some other airline's aircraft saw an inflight failure of its General Electric (GE) engine.

FAA then decided to ground all aircraft fitted with the same series of GE engines wherever they were and examine the engines before allowing them to take off. The problem, say sources, could be with the engine's "angle valve" which work as the gear box.

The AI Dreamliner (VT-ANP) operating on Delhi-Hong King-Seoul-HK-Delhi route was also fitted with the same series of GE engine and was grounded for checks by the FAA in Seoul. AI had to cancel the return leg of the flight to Delhi that this plane had to operate. The aircraft will be released after checks if the engine is found to be alright. The airline has put up stranded passengers in hotels.

The inflight engine failure is not the first trouble some GE engines fitted on Boeing 787 and 747-8 have been experiencing for some time now. But it is the most serious one.

Earlier, Boeing has asked Air India not to fly near thunderstorms as it could lead to icing on the GE engines used on it. AI has changed the routes on some sectors after this advisory.

"Boeing has issued an advisory to Air India to avoid flying the B-787 (Dreamliner) aircraft near high-level thunderstorms due to an increased risk of icing on the General Electric GEnx engines used on it," Minister of state for civil aviation G M Siddeshwara had told Parliament last month.

This issue is being witnessed possibly due to formation of ice crystals behind the main fan of the engine and then leads to a brief loss of thrust.

Boeing has changed the operating procedures for AI's Dreamliners. The new procedure reduces the risk of icing on the engines and improves safety. Icing occurs when supercooled water freezes on impact with any part of the external structure of an aircraft during flight. It can reduce a plane's performance, lead to loss of lift, stall the aircraft and result in loss of control.

Earlier, the problem of icing on certain engines of GE used on the Boeing 787 and B-747' latest version had led Boeing to ask airlines to stay away from certain clouds that have electric charge in them. Last winter, Japan airlines had withdrawn Dreamliner on Delhi-Tokyo route due to this fear. AI also got nod to fly the Dreamliner to Japan with great difficulty as a very limited airspace over China is open for civilian traffic which does not give much room for airlines to steer clear of clouds with lightening. 


- Source:  http://timesofindia.indiatimes.com