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Boeing grounds 787 test fleet
Originally published June 24, 2010 at 3:43 PM | Page modified June 24, 2010 at 4:04 PM
Boeing has grounded its 787 fleet temporarily because of a quality problem in the horizontal tails of the 787 Dreamliners built by Italian manufacturing partner Alenia.
By Dominic Gates
Seattle Times aerospace reporter
Boeing has grounded its 787 fleet temporarily because of a quality problem in the horizontal tails of the 787 Dreamliners built by Italian manufacturing partner Alenia.
The problem was discovered within the past week.
Engineers are inspecting all 23 planes already built, and some will need a fix that may take up to eight days' work.
Dreamliner program spokeswoman Yvonne Leach said Thursday the problem is "regrettable but under control."
"We made a decision to be prudent and do the inspections first," Leach said.
She said it won't cause another delay in the schedule for completing flight testing and first delivery of the new airplane, which has already been delayed by more than two and a half years.
"We're going to deal with it and we have a plan in place," Leach said.
Leach said the problem should not affect the plan to fly Dreamliner No. 3 to the Farnborough Air Show next month.
Alenia mechanics in Foggia, Italy, improperly installed brackets used to attach the horizontal tail to the fuselage, according to a person familiar with the problem.
The error, which was discovered during final assembly in Everett, involved small pieces of composite material, called shims, that are used routinely to fill small gaps when assemblying structural parts.
The shims at the horizontal tail attachment became compressed after installation and the material degraded. Potentially, this could create a small amount of play in the structural join that would increase localized stresses and could cause fractures that shorten the life of the tail attachment.
"Shims were improperly installed in a manner that could lead to lower-than-expected longevity for a joint within the horizontal stabilizer," said Leach.
"An inspection and rework plan is already implemented for airplanes in production. For those airplanes requiring rework, we expect it will take up to eight days for each airplane."
Leach said no actual cracks had been found and that the airplanes can be fixed without taking off the horizontal tail.
"It is not unusual for these issues to arise in the course of production programs," she said. "They are identified, dispositioned and dealt with through our normal processes."
Until the issue is resolved, Boeing first decided to limit the operating parameters of the flight test airplanes "to ensure continued safe operation," she said. Leach said such restrictions "are not unusual" during flight test programs. They are decided by Boeing and implemented in coordination with the Federal Aviation Administration (FAA), she said.
However, Boeing then decided to ground the flight test airplanes until the intial inspections are complete.
"Flight test airplanes will be inspected and reworked if necessary over the course of the next several weeks," Leach said.
Leach said the expectation is that Boeing can maintain its steady march toward certification.
"We expect that this issue will be addressed within the existing program schedule," Leach said. "The 787 remains on track for first delivery to ANA by the end of this year."
"Today, that's our assessment," she said, even though, until inspections are completed, Boeing won't know precisely how many Dreamliners need to be fixed.
"The airplanes are differing in the amount of re-work they need," she said. "Some have the issue and others do not. We are in the process of scoping the situation."
Airplanes that are not part of flight test and are currently on the flight line in Everett won't necessarily have to be fixed until later. Those planes are already required after certification to undergo various modifications due to other late design changes.
This is not the first issue with Alenia's workmanship.
Exactly a year ago, Boeing issued a stop-work order to Alenia's other 787 plant in Grottaglie, Italy, after Everett engineers discovered wrinkles in the 787 fuselage skins.
The wrinkles arose because the edges of the fuselage stiffening rods, called stringers, that Alenia had manufactured were way out of the specified thickness.
Boeing had to patch 22 completed barrels and strengthened subsequent barrels with thicker skin plies to accommodate the out-of-spec stringers.
Bill Dugovich, spokesman for Boeing's white-collar union, the Society of Professional Engineering Employees in Aerospace (SPEEA) said the tail problem is "yet another indication that Boeing's far-flung supply chain is not working."
Dominic Gates: 206-464-2963 or dgates@seattletimes.com
Disponível em: http://seattletimes.nwsource.com/html/busi...7_boeing25.html
Originally published June 24, 2010 at 3:43 PM | Page modified June 24, 2010 at 4:04 PM
Boeing has grounded its 787 fleet temporarily because of a quality problem in the horizontal tails of the 787 Dreamliners built by Italian manufacturing partner Alenia.
By Dominic Gates
Seattle Times aerospace reporter
Boeing has grounded its 787 fleet temporarily because of a quality problem in the horizontal tails of the 787 Dreamliners built by Italian manufacturing partner Alenia.
The problem was discovered within the past week.
Engineers are inspecting all 23 planes already built, and some will need a fix that may take up to eight days' work.
Dreamliner program spokeswoman Yvonne Leach said Thursday the problem is "regrettable but under control."
"We made a decision to be prudent and do the inspections first," Leach said.
She said it won't cause another delay in the schedule for completing flight testing and first delivery of the new airplane, which has already been delayed by more than two and a half years.
"We're going to deal with it and we have a plan in place," Leach said.
Leach said the problem should not affect the plan to fly Dreamliner No. 3 to the Farnborough Air Show next month.
Alenia mechanics in Foggia, Italy, improperly installed brackets used to attach the horizontal tail to the fuselage, according to a person familiar with the problem.
The error, which was discovered during final assembly in Everett, involved small pieces of composite material, called shims, that are used routinely to fill small gaps when assemblying structural parts.
The shims at the horizontal tail attachment became compressed after installation and the material degraded. Potentially, this could create a small amount of play in the structural join that would increase localized stresses and could cause fractures that shorten the life of the tail attachment.
"Shims were improperly installed in a manner that could lead to lower-than-expected longevity for a joint within the horizontal stabilizer," said Leach.
"An inspection and rework plan is already implemented for airplanes in production. For those airplanes requiring rework, we expect it will take up to eight days for each airplane."
Leach said no actual cracks had been found and that the airplanes can be fixed without taking off the horizontal tail.
"It is not unusual for these issues to arise in the course of production programs," she said. "They are identified, dispositioned and dealt with through our normal processes."
Until the issue is resolved, Boeing first decided to limit the operating parameters of the flight test airplanes "to ensure continued safe operation," she said. Leach said such restrictions "are not unusual" during flight test programs. They are decided by Boeing and implemented in coordination with the Federal Aviation Administration (FAA), she said.
However, Boeing then decided to ground the flight test airplanes until the intial inspections are complete.
"Flight test airplanes will be inspected and reworked if necessary over the course of the next several weeks," Leach said.
Leach said the expectation is that Boeing can maintain its steady march toward certification.
"We expect that this issue will be addressed within the existing program schedule," Leach said. "The 787 remains on track for first delivery to ANA by the end of this year."
"Today, that's our assessment," she said, even though, until inspections are completed, Boeing won't know precisely how many Dreamliners need to be fixed.
"The airplanes are differing in the amount of re-work they need," she said. "Some have the issue and others do not. We are in the process of scoping the situation."
Airplanes that are not part of flight test and are currently on the flight line in Everett won't necessarily have to be fixed until later. Those planes are already required after certification to undergo various modifications due to other late design changes.
This is not the first issue with Alenia's workmanship.
Exactly a year ago, Boeing issued a stop-work order to Alenia's other 787 plant in Grottaglie, Italy, after Everett engineers discovered wrinkles in the 787 fuselage skins.
The wrinkles arose because the edges of the fuselage stiffening rods, called stringers, that Alenia had manufactured were way out of the specified thickness.
Boeing had to patch 22 completed barrels and strengthened subsequent barrels with thicker skin plies to accommodate the out-of-spec stringers.
Bill Dugovich, spokesman for Boeing's white-collar union, the Society of Professional Engineering Employees in Aerospace (SPEEA) said the tail problem is "yet another indication that Boeing's far-flung supply chain is not working."
Dominic Gates: 206-464-2963 or dgates@seattletimes.com
Disponível em: http://seattletimes.nwsource.com/html/busi...7_boeing25.html
