Japan airlines are known for being aware of safety. It has pulled certain Boeings from flying in particular international routes due to the risk of ice forming on engines. The pilots have been asked to avoid thunderstorms which may form ice crystals. Boeing 787 has been taken off from routes where the icing conditions are not favorable for flying. This decision of Japan airlines has surprised General Electric. According to the warning notice GEnx-1B-powered 787-8s and GEnx-2B-powered 747-8s pilots should stay 50 nautical miles away from high level thunderstorms. Japan airlines express its concern over the risk of ice forming on the Boeings and the harm they could cause to the engines which have been manufactured by General Electric.
The thunderstorms can form ice particles in the high altitude. It is a short term decision taken by Japan Airlines and will be operative till new improvements are made in the engine controlled software by the following year. The decision to pull the airlines off the dangerous areas was taken after five Boeing 747-8 and one 787 experienced a momentary loss of thrust. The Boeings were flying in high altitude. The warning which Japan airlines gave was received with mixed signals. Some felt it was an overtly cautious step while others felt that it signifies the strained relation of the Boeing and the airlines.
Boeing 787 was pulled off from the subtropical zones. The connection between JAL and Boeing has been going from bad to worse because of the interruptions due to 787 and consequently the service and entry problems. When the carrier acquired the Airbus A350-900 and -1000 the rapport between the two worsened. As per the Boeing advisory’s warning JAL is dismissing the services of 787 from Singapore, New Delhi and Tokyo. It has further plans of suspending the service from Sydney. Since the 90’s this sub-tropical zone, has been facing the trouble of ice formations. The airlines have been experiencing frequent instances of ice crystal icing with the growing number of airlines in this route.
To find a solution to the problem GE and Boeing are putting in efforts to discover new and advanced engine control software. They are aiming at discovering software which will start operating in the first half of 2014. GEnx-2B-powered 747-8 was flown on trial with new and changed engine control. It is designed to detect ice particles. The engine control software opens variable bleed valve doors if the presence of ice is detected. The valves are located behind the fan, and a low pressure compressor is used to emit the ice particles. The ice particles build up is ejected before the particles enter the core of the engine.
A complicated process is used to combat the problem of ice crystals. It differs from the traditional engine icing in which the cool liquid freezes when it comes in contact with the bare engine parts as the aircraft charts its course through the clouds. In engine core ice accretion, the ice particles stick to a warm metal surface. As the surface becomes cooler and drops below the freezing point it forms a store for ice and water. This prevents the ice from entering the core and minimizes faults and breakdowns. Till recent times it was believed that the ice particles would rebound or pass through bypass ducts. The ice-core events have taken place above 22,000 feet, the upper limit for clouds containing super cooled water. Thus, the chances of super cooled water causing malfunction are ruled out.