By Alwyn Scott and Tim Hepher
NEW YORK, March 7 Boeing Co said on
Friday that "hairline cracks" had been discovered in the wings
of about 40 787 Dreamliners that are in production, marking
another setback for the company's newest jet.
The cracks have not been found on planes that are in use by
airlines and therefore pose no safety risk, Boeing said, adding
the problem also will not alter Boeing's plans to deliver 110
787s this year.
However, Boeing said the cracks, which also occurred on the
larger 787-9 model currently undergoing flight tests, could
delay by a few weeks the date when airlines can take delivery of
their new planes.
The disclosure raised questions about repair costs and a
possible minor increase in the weight of the plane, but did not
seem to spell major trouble for Boeing, industry experts said.
Wing-maker Mitsubishi Heavy Industries Ltd notified
Boeing in February of the problem, which arose after the
Japanese company altered its manufacturing process.
"We are discussing with Boeing how to deal with the
problem," a spokesman for Mitsubishi Heavy Industries in Tokyo
said. He was unable to comment on why the company changed the
Boeing, based in Chicago, said it immediately notified
customers of potential delays. It said none of the jets
potentially affected by the problem has been delivered.
"We are confident that the condition does not exist in the
in-service fleet," Boeing spokesman Doug Alder said.
The U.S. regulator said it is aware of the situation.
"The FAA will work with Boeing to ensure that the issues are
corrected before the airplanes are delivered," the Federal
Aviation Administration said in a statement.
Boeing shares fell 54 cents, or 0.4 percent, to $128.00 in
The cracks are the latest trouble for the Dreamliner, a
high-tech jet largely made of carbon-fiber composite that has
been beset with so-called "teething issues" since entering
service in 2011, three years behind schedule.
Last year, lithium-ion batteries overheated on two
Dreamliners, prompting regulators to ground the worldwide fleet
for more than three months while Boeing redesigned the battery
system. Another battery overheated this year.
Airbus also has struggled with wing cracks on its
"If they can keep the delivery schedule going, it shouldn't
be a major problem for customers," said Richard Aboulafia,
aerospace analyst at the Teal Group in Fairfax, Virginia.
"But there is an expense."
He added that the manufacturing change was probably aimed at
reducing the weight of the plane, as was the case with the A380.
"If they have to revisit that, it could add weight to the
design, though only a modest amount," he said.
Boeing said the 787 cracks occurred in shear ties on wing
ribs, and will take one to two weeks to inspect and fix.
Wing ribs run parallel to the fuselage of the plane. The
ties, made of aluminum, hold the rib to the skin of the wing and
will be replaced with an aluminum part.
"If we find an affected area, we'll correct the issue by
trimming out the area and applying a fabricated piece in its
place," Alder said.
Boeing declined to discuss the manufacturing change that led
to the problem.
Boeing expects to deliver 110 787s this year, and to earn
revenue of between $87.5 billion and $90.5 billion. So far it
has delivered nine, including one delivered on Friday.
"Deliveries continue as normal outside this potentially
impacted 40," Alder said.
Boeing's disclosure comes as Airbus emerges from a painful
two-year program of modifications and hundreds of millions of
euros of financial charges triggered by the discovery of cracks
on brackets attached to wing ribs on the A380.
Reuters reported on Thursday that Airbus had once again
ordered more frequent inspections of the wings of the world's
largest passenger jet after discovering unexpected levels of
metal fatigue, this time during testing on a factory mock-up.
The planemaker has asked airlines to inspect the wing's
"spars" or main internal beams during regular major overhauls
carried out after six years in service, and then again at 12
years, instead of waiting for the 12-year overhaul, industry
An Airbus spokeswoman confirmed the discovery of unspecified
"fatigue findings" on a factory test plane.
"This will be addressed during routine maintenance
inspections and the aircraft remains safe to fly," she said.
Most aircraft undergo a regular pattern of checks from small
daily ones to heavy maintenance checks every five or six years.
Aircraft industry experts have known for decades that metal
fatigue cannot be eliminated, but they have worked out a system
for monitoring it backed up by mandatory maintenance schedules.