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Friday, April 26, 2013

Boeing teams get to work on putting 787s back into flight

After waiting three months with its 787 Dreamliners grounded across the globe, Boeing wasted little time Friday in starting the modifications that will allow the planes to resume flying.


After waiting three months with its 787 Dreamliners grounded across the globe, Boeing wasted little time Friday in starting the modifications that will allow the planes to resume flying.
Teams of mechanics began making fixes to the 787’s lithium ion battery system as soon as the Federal Aviation Administration formalized its approval Friday afternoon.
United, the sole U.S. 787 operator, could fly one within a week, though the initial flights likely will be without passengers.
A United pilot, speaking on condition of anonymity, said the airline will first fly the planes with passengers on domestic routes out of Houston, but is “very anxious” to start using the 787 between Denver and Tokyo.
So it’s good news for both United and Boeing that the FAA did not alter the Dreamliner’s ETOPS (“extended operations”) certification, which means the 787 keeps its regulatory approval to fly up to three hours away from the nearest airport.
“I’m looking forward to flying it,” the pilot said.
More than 300 specialists will make the battery system modifications, which should take about five days per jet. Boeing said they also will upgrade the 787’s electrical generators and will inspect and if necessary replace power distribution panels that have proved unreliable.
“We’re very excited and happy to be headed down this path now,” said Boeing vice president Mike Sinnett, chief project engineer on the 787, in a conference call with journalists. “It’s been a long haul, that’s for sure.”
The 787 has been grounded since Jan. 16 after two battery overheating incidents. One battery caught fire on an empty jet parked in Boston; another smoldered on a flight in Japan and forced an emergency landing and slide evacuation.
Sinnett declined to speculate on how long it will take airlines to get the 787 back into passenger service, saying only it will be “in the near term.”
The airplanes will be modified in approximately the order they were delivered, which puts the Japanese airlines first in line.
The FAA, having certified the battery re-design, will issue a new Airworthiness Directive early next week mandating its installation to allow passenger service.
But regulators in other countries wil have to follow the FAA’s lead before foreign carriers can fly passengers.
After the new batteries are installed, the logistics of moving airplanes and support needs into place will vary from airline to airline. They also will have different requirements for functional check flights and pilot refresher training, and will need time to reschedule flights and sell tickets on routes that have been suspended.
The worldwide fleet of 50 in-service Dreamliners is unlikely to resume all planned 787 passenger routes worldwide before June.
The unprecedented setback of the grounding will cost Boeing more than $600 million just to pay for the labor and parts in developing, testing, certifying and retrofitting the fix, according to one Wall Street analyst’s estimate.
Beyond that, it will undoubtedly owe compensation to airlines for lost revenue. That can’t be reliably estimated because some customers will take price breaks on future orders instead of cash.
Boeing executives, understandably, were jubilant at the FAA’s clearance to fly.
CEO Jim McNerney said “the promise of the 787 and the benefits it provides to airlines and their passengers remain fully intact.”
The redesigned battery “made a great airplane even better,” said Boeing Commercial Airplanes CEO Ray Conner.
Federal regulators, led by Transportation Secretary Ray LaHood, insisted that their decision to give the Dreamliner the green light to fly again doesn’t weaken their committment to safety.
FAA Administrator Michael Huerta said he approved the fix only after “a team of FAA certification specialists observed rigorous tests ... and devoted weeks to reviewing detailed analysis of the design changes.”
Sinnett said Boeing spent a total of 200,000 engineering hours developing its solution and 100,000 hours testing it.
The modifications include a steel containment box around the battery and a titanium tube connecting the box to the fuselage skin. If the battery overheats, the tube will suck out any gases, including oxygen, from the box.
This “completely prevents any possibility of fire,” Sinnett said. Indeed, he said the enclosure and venting system is designed to be so safe that “a worst-case battery failure doesn’t even require the airplane to divert.”
Engineers also added electrical and thermal insulation around the eight cells of the battery to minimize short circuits and prevent any overheating from spreading cell to cell.
Sinnett provided details from Boeing’s lab tests that he said demonstrate the efficacy of the internal battery design changes.
When Boeing forced a cell failure by using a heating element to cook a cell inside the original battery design, the temperature hit 300 degrees Celsius for half an hour after the first cell ruptured and vented gas, and caused all the other cells to overheat and vent.
On the new battery design the same test yielded a very brief peak temperature of less than 150 degrees C, and only two cells overheated enough to vent.
Two fresh aspects of Friday’s 787 announcements provide good news for airlines.
First, the FAA’s decision not to reduce the 787’s ETOPS certication will come as a relief, after the head of the agency, Huerta, told a Senate hearing Tuesday that this approval was under review.
Maintaining the three-hour allowed flight time away from the nearest airport is crucial to the jet’s use for flying long routes over the ocean or the poles, a key feature for airlines.
Second, Boeing’s decision to take the opportunity to replace or upgrade other electrical 787 components may improve reliability, particularly of the power panels.
Last December, a United 787 had to divert after a power panel short circuit caused a generator to go offline. That was one of at least four such inflight failures last year, which Boeing later blamed on bad circuit boards in the power panels.
In addition to replacing those, if necessary, Sinnett said the battery teams will check that each plane’s six electric generators are “up to the latest standard.”
U.S. Rep. Rick Larsen, D-Everett, welcomed the 787’s clearance, while cautioning that the battery failures in January demand more investigation.
He said that during a late March briefing by the company on the battery fix, “I was impressed with the ingenuity the Boeing engineers put into this.”
However, “once the fixes are done and these planes are back up and flying, Congress needs to go back and look at the certification process and figure out how did we ever get to this place,” said Larsen, the ranking Democrat on the House Aviation Subcommittee.
That scrutiny is set to begin Tuesday when the National Transportation Safety Board opens two days of hearings into the original design and certification of the 787 batteries.
Witnesses scheduled to appear include Boeing’s Sinnett and some of his technical staff, as well as top FAA certification personnel and managers from battery system supplier Thales of France and battery-maker GS Yuasa of Japan.
Friday, Sinnett said that Boeing will closely analyze what went wrong on the 787 battery design and learn from it for the future.
“There will be some very significant attention given to this and what we have to learn from it,” Sinnett said.


seattletimes.com

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