The specialist aviation blog Leeham News, which first reported the discovery of the “foreign object debris” (FOD), said it was unlikely that the inspections would delay the recertification of the jets. However, it will take up to three days to inspect each plane because fuel must be drained and vapours dissipated before the fuel tanks can be opened.
Mark Jenks, the general manager of the 737 programme, said in a memo to employees that the debris was “absolutely unacceptable” and that the company was taking steps to address the problem in its production system.
“During these challenging times, our customers and the flying public are counting on us to do our best work each and every day,” Jenks said, adding: “One escape is one too many.”
It is less than a year since the second fatal crash of a Boeing 737 Max resulted in the grounding of the model’s entire global fleet and the company is racing to recertify with regulators that the planes can fly safely.
The fuel tank problem is unrelated to the flaws to sensors thought to have contributed towards the two crashes.