Boeing has notified airlines of another problem with its 737 model, following two fatal crashes involving one variant.
In this case, the issue goes beyond the 737 MAX variant and affects a wing part on hundreds of aircraft worldwide.
A Lion Air 737 MAX crashed in Indonesia last October
Boeing said it had contacted operators of the 737 advising them to inspect the slat track assemblies on certain airplanes.
‘One batch of slat tracks with specific lot numbers produced by a supplier was found to have a potential nonconformance. If operators find the parts in question, they are to replace them with new ones before returning the airplane to service,’ the manufacturer said.
According to Boeing, slat tracks are used to guide the slats located on the leading edge of an airplane’s wings.
It said it ‘has not been informed of any in-service issues related to this batch of slat tracks’.
The US Federal Aviation Administration (FAA) said: ‘Following an investigation conducted by Boeing and the FAA Certificate Management Office (CMO), we have determined that up to 148 parts manufactured by a Boeing sub-tier supplier are affected.
‘Boeing has identified groups of both 737NG and 737MAX airplane serial numbers on which these suspect parts may have been installed. 32 NG and 33 MAX are affected in the U.S. Affected worldwide fleet are 133 NG and 179 MAX aircraft.’
It warned: ‘The affected parts may be susceptible to premature failure or cracks resulting from the improper manufacturing process. Although a complete failure of a leading edge slat track would not result in the loss of the aircraft, a risk remains that a failed part could lead to aircraft damage in flight.’