Aviator
2015-04-26 18:35:41
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B787 är en skam för Boeing och USA
A Japan Airlines (JAL) 787 experienced a fuel leak on January 8, 2013, and its flight from Boston was canceled.[320] 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 Boardsubsequently opened a safety probe.[321]Later, on January 11, 2013, another aircraft was found to have a fuel leak.[322]
Also on January 11, 2013, the FAA completed 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".[323]
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.[324] This leak was caused by a different valve; the causes of the leaks are unknown.[325] Japan's transport ministry has also launched an investigation.[326]
On July 12, 2013, a fire started on an emptyEthiopian Airlines 787 parked at Heathrow Airport before it was put out by the airport fire and rescue service. No injuries were reported.[327][328] The fire caused extensive heat damage to the aircraft.[329] The FAA and NTSB sent representatives to assist in the investigation.[330] The initial investigation found no direct link with the aircraft's main batteries.[331] Further investigations indicated that the fire was due to lithium-manganese dioxide batteries powering an emergency locator transmitter (ELT).[332][333] 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.[334]
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.[335]On August 14, 2013, the media reported a fire extinguisher fault affecting three ANA airplanes,[336] which was caused by a supplier assembly error.[337]
On September 28, 2013, Norwegian Long Hauldecided 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.[338] The company will lease anAirbus A340 for its long-haul operations while the 787 is returned to Boeing for repair.[339]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.[340][341]
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 buildup of ice crystals just behind the main fan, causing a brief loss of thrust on six occasions.[342]
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.[343] Footage of the leak taken by passengers show fuel gushing out of the left wing of the aircraft.[344] The leak became known to pilots only after it was pointed out by concerned passengers.[345] It was found later that a faulty valve was responsible.[346]This fuel leak is one of numerous problems experienced by Norwegian Air Shuttle's 787 fleet.[343] 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”.[347][348]
Battery problemsEdit
Main 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 AirwaysFlight 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 (65 km) west of Takamatsu, 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 atBoston's Logan International Airport within the same week led the Federal Aviation Administration to ground all Boeing 787s in service at the time.[349]
On January 16, 2013, both major Japanese airlines ANA and JAL voluntarily grounded their fleets of 787s after multiple incidents involving different 787s, including emergency landings. At the time, these two carriers operated 24 of the 50 Dreamliners delivered.[350][351] The grounding is reported to have cost ANA some 9 billion yen (US$93 million) in lost sales.[352][353]
On January 16, 2013, the FAA issued anemergency 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.[354] This was the first time that the FAA has grounded an airliner type since 1979.[355] Industry experts disagreed on consequences of the grounding: Airbus was confident that Boeing would resolve the issue[356] and that no airlines will switch plane type,[357] while other experts saw the problem as "costly"[358] and "could take upwards of a year".[359]
The FAA also conducted an extensive review of the 787's critical systems. The focus of the review was on the safety of the lithium-ion batteries[355] made of lithium cobalt oxide(LiCo). The 787 battery contract was signed in 2005,[197] when LiCo batteries were the only type of lithium aerospace battery available, but since then newer and safer[360] types (such as LiFePO), which provide less reaction energy during thermal runaway, have become available.[195][361] FAA approved a 787 battery in 2007 with nine "special conditions".[362][363]A battery approved by FAA (through Mobile Power Solutions) was made by Rose Electronics using Kokam cells;[364] the batteries installed in the 787 are made by Yuasa.[193]
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,[365] and the charging unit passed tests. The battery had signs of short circuitingand thermal runaway.[366] Despite this, by January 24, the NTSB had not yet pinpointed the cause of the Boston fire; the FAA would not allow Dreamliners based in the U.S. to fly again until the problem was 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.[367]
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[368] to near zero.[369] All cells had signs of thermal damage before thermal runaway.[370] ANA and JAL had replaced several 787 batteries before the mishaps.[369]As of January 29, 2013, JTSB approved the Yuasa factory
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