(CNN) — Federal authorities say they’re investigating Boeing after a whistleblower repeatedly raised concerns with two widebody jet models, and claimed the company retaliated against him.

Whistleblower Sam Salehpour, a Boeing engineer, alleges that Boeing took shortcuts when manufacturing its 777 and 787 Dreamliner jets, and that the risks could become catastrophic as the airplanes age. The New York Times was first to report the whistleblower complaint.

His formal complaint to the Federal Aviation Administration, filed in January and made public on Tuesday, is not specific to the newer 737 Max jet that has been grounded twice by the Federal Aviation Administration.

Salehpour on Tuesday said his complaint raises “two quality issues that may dramatically reduce the life of the planes.”

“I am doing this not because I want Boeing to fail, but because I want it to succeed and prevent crashes from happening,” Salehpour told reporters on a conference call Tuesday. “The truth is Boeing can’t keep going the way it is. It needs to do a little bit better, I think.”

The FAA has interviewed Salehpour as part of its investigation, his attorney Lisa Banks said. The FAA said it investigates all whistleblower complaints.

“Voluntary reporting without fear of reprisal is a critical component in aviation safety,” the FAA said.  “We strongly encourage everyone in the aviation industry to share information.”

A Senate subcommittee will also take up the concerns at a hearing next week.

Boeing did not immediately comment on the claims about the 777, but disputed Salehpour’s concerns about the 787.

“These claims about the structural integrity of the 787 are inaccurate and do not represent the comprehensive work Boeing has done to ensure the quality and long-term safety of the aircraft,” the company said in a statement.

Gaps in the Dreamliner

Boeing’s 787 Dreamliner planes, which entered service in 2011, could have 50-year lifespans – around 44,000 flights each, the company says.

But Salehpour’s complaint alleges crews assembling the plane failed to properly fill tiny gaps when joining separately manufactured parts of the fuselage. That puts more wear on the plane, shortening its lifespan and risking “catastrophic” failure, Salehpour’s attorneys alleged.

The allegations aren’t entirely new: For nearly two years starting in 2021, the FAA and Boeing halted deliveries of the new Dreamliners while it looked into the gaps. Boeing said it made changes in its manufacturing process, and deliveries ultimately resumed.

“We incorporated the join inspection and verification activity into our production system so that airplanes coming off of the production line meet these specifications,” Boeing said.

The 787 Dreamliners were not grounded, but the FAA twice investigated questions about quality control during the jet’s assembly process. The company maintained that the planes were and are safe to fly.

Salehpour’s attorneys said the FAA was surprised to discover through his complaint that the gaps were still an issue.

“I literally saw people jumping on the pieces of the airplane to get them to align,” Salehpour said. “By jumping up and down, you’re deforming parts so that the holes align temporarily … and that’s not how you build an airplane.”

Alleged retaliation led to another discovery

Salehpour said Boeing retaliated against him after he raised another concern about the 787 and a different plane model.

The whistleblower complaint said he pointed out to management the existence of drilling issues with the 787, and was then “ignored and ultimately transferred out of the 787 program to the 777 program.”

In his new role, Salehpour said he discovered subpar work with aligning body pieces, and pressure on engineers to green-light work they have not yet inspected.

In all, Salehpour said the issues involve more than 400 777s and 1,000 787s.

Boeing (BA) shares fell 2% Tuesday.

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