Saturday, April 12, 2014

Boeing 787 Operational problems

The Boeing 787 has been involved in multiple aviation incidents and operational problems. In December 2012, Boeing CEO James McNerney stated that the problems were no greater than those experienced with the introduction of other models such as the Boeing 777.[294][295]
Operational problems[edit]

A Japan Airlines (JAL) 787 experienced a fuel leak on January 8, 2013, and its flight from Boston was canceled.[296] On January 9, United Airlines reported a problem in one of its six 787s with the wiring near the main batteries. After these incidents, the U.S. National Transportation Safety Board subsequently opened a safety probe.[297] Later, on January 11, 2013, another aircraft was found to have a fuel leak.[298]

Also on January 11, 2013, the FAA announced a comprehensive review of the 787's critical systems, including the design, manufacture and assembly; the Department of Transportation secretary Ray LaHood stated the administration was "looking for the root causes" behind the recent issues. The head of the FAA, Michael Huerta, said that so far nothing found "suggests [the 787] is not safe".[299]

On January 13, 2013, a JAL 787 at Narita International Airport outside Tokyo, was found to also have a fuel leak during an inspection, the third time a fuel leak had been reported within a week. The aircraft reportedly was the same one that had a fuel leak in Boston on January 8.[300] This leak was caused by a different valve; the causes of the leaks are unknown.[301] Japan's transport ministry has also launched an investigation.[302]

On July 12, 2013, a fire started on an empty Ethiopian Airlines 787 parked at Heathrow Airport before it was put out by the airport fire and rescue service. No injuries were reported.[303][304] The fire caused extensive heat damage to the aircraft.[305] The FAA and NTSB sent representatives to assist in the investigation.[306] The initial investigation found no direct link with the aircraft's main batteries.[307] Further investigations indicated that the fire was due to lithium-manganese dioxide batteries powering an emergency locator transmitter (ELT).[308][309] The UK Air Accidents Investigation Branch (AAIB) issued a special bulletin on July 18, 2013 requesting the US FAA ensure that the locator is removed or disconnected in Boeing 787s, and to review the safety of lithium battery-powered ELT systems in other aircraft types.[310]

On July 26, 2013, ANA said it had found wiring damage on two 787 locator beacons. United Airlines also reported that it had found a pinched wire in one 787 locator beacon.[311] On August 14, 2013, the media reported a fire extinguisher fault affecting three ANA airplanes,[312] which was caused by a supplier assembly error.[313]

On September 25, 2013, the Wall Street Journal reported that all of the five Dreamliners owned by LOT had been grounded for inspection for missing low pressure fuel filters. One 787 was found with none in both engines and another was missing a filter in one engine.[314] On September 28, 2013, a LOT 787 had to divert to Reykjavik due to a faulty self-identification system.[315]

On September 28, 2013, Norwegian Long Haul decided to take one of its two 787s in its fleet at the time out of service after the two aircraft broke down on more than six occasions in September.[316] The company will lease anAirbus A340 for its long-haul operations while the 787 is returned to Boeing for repair.[317] On December 20–22, 2013, Norwegian Long Haul experienced technical problems keeping two of its three 787 aircraft grounded at Fort Lauderdale airport and delayed six flights.[318][319]

On October 15, 2013, an Air India flight from New Delhi to Bangalore lost an 8 ft by 4 ft fairing panel from its underside before landing safely.[320] On November 4, 2013, an Air India flight from Sydney to Melbourne experienced a cracked window shortly before safely landing at Melbourne.[321]

On November 22, 2013, Boeing issued an advisory to airlines using General Electric GEnx engines on 787 and 747-8 aircraft to avoid flying near high-level thunderstorms due to an increased risk of icing on the engines. The problem was caused by a build up of ice crystals just behind the main fan, causing a brief loss of thrust on six occasions.[322]

On January 21, 2014, a Norwegian Air Shuttle 787 experienced a fuel leak which caused a 19-hour delay to a flight from Bangkok to Oslo.[323] Footage of the leak taken by passengers show fuel gushing out of the left wing of the aircraft.[324] The leak became known to pilots only after it was pointed out by concerned passengers.[325] It was found later that a faulty valve was responsible.[326] This fuel leak is one of numerous problems experienced by Norwegian Air Shuttle's 787 fleet.[323] Mike Fleming, Boeing's vice president for 787 support and services, subsequently met with executives of Norwegian Air Shuttle and expressed Boeing's commitment to improving the 787's dispatch reliability, "we’re not satisfied with where the airplane is today, flying at a fleet average of 98 percent... The 777 today flies at 99.4 percent ... and that's the benchmark that the 787 needs to attain”.[327][328] Dispatch reliability is an industry standard measure of the rate of departure from the gate with no more than 15 minutes delay due to technical issues.[329][330]
Battery problemsMain article: Boeing 787 Dreamliner battery problems

The Aft Electronics Bay that held the JAL 787 battery that caught fire

Japan Airlines 787 battery comparison; Left: typical original battery. Right: damaged battery.

On January 16, 2013, All Nippon Airways Flight NH-692, en route from Yamaguchi Ube Airport to Tokyo Haneda, had a battery problem warning followed by a burning smell while climbing from Ube about 35 nautical miles west ofTakamatsu, Japan. The aircraft diverted to Takamatsu and was evacuated via the slides; three passengers received minor injuries during the evacuation. Inspection revealed a battery fire. A similar incident in a parked Japan Airlines 787 at Boston's Logan International Airport within the same week led the Federal Aviation Administration to ground all Boeing 787s in service at the time.[331]

On January 16, 2013, both major Japanese airlines ANA and JAL announced that they were voluntarily grounding or suspending flights for their fleets of 787s after multiple incidents involving different 787s, including emergency landings. These two carriers operate 24 of the 50 Dreamliners delivered to date.[332][333] The grounding is reported to have cost ANA some 9 billion yen (US$93 million) in lost sales.[334][335]

On January 16, 2013, the FAA issued an emergency airworthiness directive ordering all American-based airlines to ground their Boeing 787s until yet-to-be-determined modifications were made to the electrical system to reduce the risk of the battery overheating or catching fire.[336] This was the first time that the FAA has grounded an airliner type since 1979.[337] Industry experts disagreed on consequences of the grounding: Airbus was confident that Boeing would resolve the issue[338] and that no airlines will switch plane type,[339] while other experts saw the problem as "costly"[340] and "could take upwards of a year".[341]

The FAA also announced plans to conduct an extensive review of the 787's critical systems. The focus of the review will be on the safety of the lithium-ion batteries[337] made of lithium cobalt oxide (LiCo). The 787 battery contract was signed in 2005,[193] when LiCo batteries were the only type of lithium aerospace battery available, but since then newer and safer[342] types (such as LiFePO), which provide less reaction energy during thermal runaway, have become available.[191][343] FAA approved a 787 battery in 2007 with nine "special conditions".[344][345] A battery approved by FAA (through Mobile Power Solutions) was made by Rose Electronics using Kokam cells;[346] the batteries installed in the 787 are made by Yuasa.[189]

On January 20, the NTSB declared that overvoltage was not the cause of the Boston incident, as voltage did not exceed the battery limit of 32 V,[347] and the charging unit passed tests. The battery had signs of short circuitingand thermal runaway.[348] Despite this, the NTSB announced on January 24 that it had not yet pinpointed the cause of the Boston fire; the FAA will not allow Dreamliners based in the U.S. to fly again until the problem is found and corrected. In a press briefing that day, NTSB Chairwoman Deborah Hersman said that the NTSB had found evidence of failure of multiple safety systems designed to prevent these battery problems, and stated that fire must never happen on an airplane.[349]

The Japan Transport Safety Board (JTSB) has said on January 23 that the battery in ANA jets in Japan reached a maximum voltage of 31 V (below the 32 V limit like the Boston JAL 787), but had a sudden unexplained voltage drop[350] to near zero.[351] All cells had signs of thermal damage before thermal runaway.[352] ANA and JAL had replaced several 787 batteries before the mishaps.[351] As of January 29, 2013, JTSB approved the Yuasa factoryquality control[353][354] while the NTSB continues to look for defects in the Boston battery.[355] The two major battery thermal runaway events in 100,000 flight hours was much higher than the rate of one in 10 million flight hours that Boeing predicted.[331]

The only American airline that operated the Dreamliner at the time was United Airlines, which had six.[356] Chile's Directorate General of Civil Aviation (DGAC) grounded LAN Airlines' three 787s.[357] The Indian Directorate General of Civil Aviation (DGCA) directed Air India to ground its six Dreamliners. The Japanese Transport Ministry made the ANA and JAL groundings official and indefinite following the FAA announcement.[358] The European Aviation Safety Agency has also followed the FAA's advice and grounded the only two European 787s operated by LOT Polish Airlines.[359] Qatar Airways has announced that they are grounding their five Dreamliners.[360] Ethiopian Airlines was the final operator to announce temporary groundings of its four Dreamliners.[361] By January 17, 2013, all 50 of the aircraft delivered to date had been grounded.[361][362]

On January 18, Boeing announced that it was halting 787 deliveries until the battery problem is resolved.[363] On February 7, 2013, the FAA gave approval for Boeing to conduct 787 test flights to gather additional data.[364][365] In February 2013, FAA oversight into the 2007 safety approval and certification of the 787 have come under scrutiny.[366]

On March 7, 2013, the National Transportation Safety Board released an interim factual report about the 787 battery fire at Boston's Logan Airport on January 7, 2013. The investigation[367] stated that "heavy smoke and fire coming from the front of the APU battery case". Firefighters "tried fire extinguishing, but smoke and flame (flame size about 3 inches) did not stop".[368][369]

Boeing completed its final tests on a revised battery design on April 5, 2013. Qatar Airways said it expected to have its Dreamliners back in revenue service by the end of April.[370] The FAA approved Boeing's revised battery design with three additional, overlapping protection methods on April 19, 2013. The FAA published a directive on April 25 to provide instructions for retrofitting battery hardware before the 787s can return to flight.[371][372] The repairs are expected to be completed in weeks.[373]

Following the FAA approval in the United States,[374] Japan gave permission for passenger airlines to resume Boeing 787 flights in the country effective April 26, 2013.[375] On April 27, 2013, Ethiopian Airlines took a 787 on the model's first commercial flight after battery system modifications.[372][374]

On January 14, 2014, a battery in a JAL 787 emitted smoke from the battery's protection exhaust while the aircraft was undergoing pre-flight maintenance.[376][377] The battery partially melted in the incident;[378] one of its eight lithium-ion cells had its relief port vent and fluid sprayed inside the battery's container.[379] It was later reported that the battery may have reached a temperature as high as 660 Celsius, and that Boeing did not understand the root cause of the failure.[380]