(New York) An aircraft mechanic has contacted the American civil aviation regulator, the FAA, to alert it of possible assembly and maintenance defects on 787 aircraft, which Boeing claims have already been addressed.

Richard Cuevas worked, on a contract basis but not as an employee, for Spirit AeroSystems, Boeing’s main subcontractor, according to his lawyers, Debra Katz and Lisa Banks.

As part of its Boeing aircraft repair work, the whistleblower said it observed quality practices “below standards” concerning a bulkhead of the fuselage of the 787, a long-haul aircraft.

In detail, workers would have drilled too large holes in this part of the device, which led to a risk of electrical failure and depressurization in flight, according to him.

Mr. Cuevas says he has seen these defects on three planes and estimates that at least ten to twelve 787s could be affected.

He also indicates that he witnessed the improper application of a waterproofing coating.

The mechanic made a report to Spirit AeroSystems, then to Boeing.

But neither company “corrected these practices,” according to the whistleblower’s lawyers. “Mr. Cuevas was fired [in March 2024] after his manager suspected him of being the source of the report.”

Boeing told AFP that it had carried out investigations after a report by a “contract worker of a subcontractor” and said it had “addressed” the questions raised by this report, “which did not present a security risk”.

“We are studying the documents submitted today and will investigate any new reports,” added the aircraft manufacturer.

“Our managers are aware of these allegations and are looking into them,” a Spirit AeroSystems spokesperson commented. “We encourage all Spirit employees to raise any concerns they may have, knowing they will be protected. »

In mid-April, four whistleblowers, including an engineer and former Boeing employees, testified before a US Senate committee of inquiry to prevent “serious problems” in the production of Boeing 737 MAX, 787 Dreamliner and 777.

The American manufacturer is going through one of the most tormented periods in its history.

Entangled in a series of production and compliance problems for several years, it saw regulators put additional pressure on it after an in-flight incident in early January.

An Alaska Airlines 737 MAX 9 aircraft had a door come loose in mid-flight, with an investigation revealing that it had been improperly secured.