A Boeing whistleblower says he saw holes being drilled incorrectly on 787 planes, adding to the chorus of people speaking up against the company

In a complaint filed by his lawyers on Tuesday to the Federal Aviation Administration, Cuevas said Spirit AeroSystems workers were drilling holes into the fasteners of the plane’s forward pressure bulkhead, which were bigger than what Boeing had specified.

They did this to “clear excess paint from the holes and speed up a slow process,” per the complaint. Cuevas said that the faults could lead to a loss of air pressure in the flight and run the risk of power failure.

However, in March, a few months after he reported his findings to Boeing and Spirit AeroSystems, he was fired from his job, the complaint said.

In a statement to BI, Boeing said it had investigated Cuevas’ concerns and determined that they were not safety threats.

“A subcontractor’s employee previously reported concerns to us that we thoroughly investigated as we take seriously any safety-related matter,” the company said. “Engineering analysis determined that the issues raised did not present a safety concern and were addressed.”

It added: “We are reviewing the documents released today and will thoroughly investigate any new claim.”

Latest in a long list of Boeing whistleblowers

Cuevas is the latest whistleblower to allege that the aircraft manufacturer has been lax with safety and quality control.

A sprawling 204-page report by the Senate subcommittee investigating Boeing’s safety and quality practices, released on June 17, cited accounts from numerous other whistleblowers.

These include Sam Mohawk, a quality assurance inspector for Boeing, who alleged that the company lost track of hundreds of faulty 737 parts and ordered staff to conceal improperly stored plane parts so that FAA inspectors would not see them.

Merle Meyers, a former Boeing quality manager, said that Boeing’s manufacturing team regularly tried to retrieve bad parts from a “reclamation” area even after they were thrown out.

John Barnett, a Boeing manager turned whistleblower, said that safety procedures were ignored in the interest of speed and efficiency in building the planes.

Just days before he was supposed to give a deposition, Barnett was found dead from a”self-inflicted gunshot wound,” the Charleston County coroner’s office told BI’s Matthew Loh. No further details were provided.

Boeing’s troubles

Boeing planes have been plagued by technical issues in recent months.

On Saturday, a Korean Air 737 Max 8 flight bound for Taiwan had to turn back and make an emergency landing after detecting a fault with the aircraft’s pressurization system.

Earlier in March, a United Airlines Boeing 777 taking off from San Francisco International Airport lost a tire just after takeoff, which crushed a car in the airport parking lot.

Most prominently, in January, a door plug came off a Boeing 737 Max 9 Alaska Airlines jet at 16,000 feet, resulting in a gaping hole in the plane.

Cuevas’ lawyers and representatives of Boeing and Spirit AeroSystems didn’t immediately respond to a request for comment from Business Insider, made outside regular working hours.