Boeing has warned fifteen airlines about high altitude ice forming on its 727-8 and 787 Dreamliner aircraft.
Some General Electric engines have dangerous ice accumulation when the airplanes fly near thunderstorms at high altitude.
Boeing told the airlines that Dreamliners using General Electric’s GEnx engines should stay at least 50 nautical miles from thunderstorms with ice crytals to avoid the risk of high altitude ice.
Japan Airlines has decided to cancel two international routes – Tokyo-Singapore and Tokyo-Delhi – because of high altitude ice. Other aircraft will be used for those flights.
A Boeing spokesman said, “Boeing and JAL share a commitment to the safety of passengers and crews on board our airplanes. We respect JAL’s decision to suspend some 787 service on specific routes.”
Six incidents of high altitude ice
Since April 2013 there have been six incidents – one 787 and five 747-8s – all of them linked to General Electric’s (GE’s) GEnx engines. High altitude ice caused the engines to suffer temporary loss of thrust.
According to GE, the problem occurs when there is a buildup of ice crystals which starts behind the front fans and runs through the engine. GE emphasized that in all six cases the aircraft reached their destinations and landed safely.
Japan Airlines (JAL) added that it is scrapping plans to use 787s for its Tokyo-Sydney flights from December 2013. The company says it will continue using Dreamliners for its other international and domestic routes as they are rarely affected by the cumulonimbus clouds which create high altitude thunderstorms.
787s are powered either by Trent 1000 (made by Rolls-Royce Plc) or GE, while all 747-8s are powered by GE engines.
Reuters quoted a GE spokesman who said “The aviation industry is experiencing a growing number of ice-crystal icing encounters in recent years as the population of large commercial airliners has grown, particularly in tropical regions of the world.”
Boeing and GE say they are improving the software to the engine control system, which will hopefully resolve the problem.
High altitude ice one of many Dreamliner problems
High altitude ice is just one of several problems Boeing’s Dreamliner aircraft have had this year.
On October 10th, Market Business News reported that JAL had to turn two Dreamliners around in mid-flight due to technical issues. In one of the flights six of the aircraft’s seven toilets suffered electrical problems and became unusable.
In June, JAL had to turn around a Tokyo-Singapore flight.
In September, budget airline Norwegian Air Shuttle complained of several glitches with its two 787 Dreamliners. One of its planes developed hydraulic pump failure at Bangkok airport. The airline had to replace the aircraft with an Airbus A340 leased from HiFly.
Below is a list of some other Dreamliner problems:
- January 8th – a JAL 787 suffered a fuel leak. The flight from Boston was cancelled.
- January 9th – United Airlines reported wiring problems near the main batteries of six aircraft.
- January 12th – JAL reported a cracked cockpit.
- January 13th – JAL reported a fuel leak at Narita International Airport in the same plane that suffered a leak in Boston. This time the problem had a different cause.
- January 16th – ANA (All Nippon Airways) reported a battery problem following by a burning smell as the aircraft left Ube Airport in Tokyo. The plane landed in a nearby airport and passengers were evacuated via the slides (three minor injuries).
- January 16th – ANA and JAL grounded their entire Dreamliner fleet.
- January 16th – the US Federal Aviation Authority grounded all Dreamliners in the USA.
- January 17th – Dreamliners were grounded around the world.
- July 12th – a fire broke out in an empty Ethiopian Airline aircraft. British inspectors said it was caused by the lithium-manganese dioxide batteries that power the emergency locator transmitter.
- July 26th – two ANA Dreamliner locator beacons had damaged wiring. United Airlines reported a pinched wire in a locator beacon.
- August 14th – faulty fire extinguishers were reported in three ANA aircraft.
- August 18th – the Aft Electronic Bay that holds the battery caught fire in a JAL aircraft.
- September 2013 – Poland’s flagship carrier, LOT, reported that its aircraft lacked gas filters. Another LOT Dreamliner flying from Canada to Norway was forced to land in Iceland (see video).