Boeing's much-delayed 787 Dreamliner has hit another production problem.
Hairline cracks have been discovered in the wings of some 787s that are being built. The Chicago-based manufacturer said none of the 122 jets already flown by airlines around the world is affected.
"We are confident that the condition does not exist in the in-service fleet," Boeing spokesman Doug Alder said.
"We understand the issue, what must be done to correct it and are completing inspections of potentially affected aeroplanes."
Boeing said that roughly 40 aeroplanes might be affected and that it will take one to two weeks to inspect each plane and fix any cracks found on shear ties on a wing rib.
Willie Walsh - chief of British Airways owner IAG - has said he remains committed to Boeing's new Dreamliner aircraft despite a series of faults.
He said that most new aircraft have "teething problems" but admitted that the grounding of an entire fleet was unusual, adding that social media had contributed to the outcry over the safety of the Dreamliner.
ITV News' Economics Editor Richard Edgar asked whether he was annoyed by the faults:
The chief of International Airlines Group - which owns British Airways - has said he has complete confidence in the Boeing 787 Dreamliner despite a series of faults.
Willie Walsh told me that the string of fires and faults are normal teething problems, which is good seeing as he is buying so many.
There has been a catalogue of Boeing 787 Dreamliner faults and groundings since the plane took to the skies.
In December, an United Airline Dreamliner made an emergency landing in New Orleans due to electrical problems.
In January 2013, a lithium ion battery pack sparked a fire on a Japan Airways Boeing 787.
Shortly, after all Dreamliners were grounded while safety checks were carried out, they were later cleared for service in April.
A decision by US aviation officials to order airlines to remove or inspect emergency beacons in Boeing 787 Dreamliners, follows a recent fire on a parked plane at Heathrow Airport.
Last week, UK air accident investigators also called for a review of the devices, after an investigation found the fire on the Ethiopian Airlines jet was caused by a fire in the transmitter.
Boeing said at the time that it supported the recommendations made in the report by the Air Accidents Investigation Branch.
The US Federal Aviation Administration has told airlines to remove or inspect beacons in Boeing 787 Dreamliners following a fire on a parked jet earlier this month at Heathrow Airport.
Boeing said it is "supporting the actions by regulators" following a blaze on one of the company's 787 Dreamliner jets at Heathrow airport last week:
US officials investigating the fire on a Boeing 787 Dreamliner jet at Heathrow airport last week are focused on how condensation in the plane and a possible pinched wire in an emergency beacon may have sparked the blaze, Reuters reported, citing an unnamed source.
The US Federal Aviation Administration (FAA) said it will call for inspections of the beacons made by the Fortune 100 firm Honeywell, but stopped short of requiring airlines to disable or remove the devices as the UK's Air Accidents Investigation Branch recommended.
The FAA said inspections should ensure wires are properly routed and should look for pinched wires or signs of unusual moisture or heat. It gave no further details on how those factors may have contributed to the fire.
But a source told Reuters that investigators had found a pinched wire in the casing of the emergency locator transmitter (ELT) on board the Ethiopian Airlines flight.
There has been a number of Boeing 787 Dreamliner faults and groundings since the plane hailed as the most environmentally friendly took to the skies.
In July 2012, a fan shaft on an engine failed during tests in South Carolina.
In December of the same year, an United Airline Dreamliner made an emergency landing in New Orleans due to electrical problems.
More recently, a Dreamliner bound for Florida returned to Manchester airport after developing a fault.