Boeing and the Federal Aviation Administration (FAA) are investigating why a landing gear was improperly installed on a new 777 jet, leading to an emergency landing at Paine Field during a test flight earlier this month.
Boeing and the Federal Aviation Administration (FAA) are investigating why a landing gear was improperly installed on a new 777 jet, leading to an emergency landing at Paine Field during a test flight in May.
Boeing said Tuesday incorrect rigging of the landing gear during final assembly caused the incident.
“It is a workmanship issue,” said Boeing spokeswoman Debbie Heathers.
Most Read Stories
She said mechanics are supposed to precisely follow an engineering document as they adjust the landing gear during assembly.
“They didn’t follow the instructions,” she said, leaving “about a quarter-inch of play” in a mechanical part of the system.
After the plane landed without incident, mechanics found a broken part in the landing gear.
The same part has since been replaced on several other 777s, said Heathers.
On May 23, Boeing voluntarily disclosed the incident to the FAA, said agency spokesman Allen Kenitzer.
The pace of manufacturing work in Everett has recently increased.
In May, production of the 777 ramped back up from five a month to seven a month.
A Boeing employee familiar with the incident said self-inspection by mechanics is increasingly the norm within the factory, and no quality inspectors signed off on the work independently of the mechanics who rigged the landing gear.
“This is a case of hurry up and get it done,” the employee said.
Heathers declined to comment on that criticism.
The incident happened May 10 during a routine test flight on a 777 newly rolled out of the factory.
During the flight, a cockpit warning message told the pilots the left main landing gear was not locked into place, said Heathers.
The pilots returned to the airfield and flew low past the air traffic control tower for a visual inspection.
Firetrucks were positioned at the edge of the runway as a precaution. However, the airplane landed safely.
Heathers said mechanics inspected the jet’s landing gear afterward and found that a cylindrical metal bearing called a bushing had broken.
Mechanics replaced the bushing and engineers signed off on the airplane, which was delivered to Etihad Airways of the United Arab Emirates a few days later than planned.
“As a precaution, we’ve been checking that part in other 777s, and in some cases we’ve been removing and replacing it,” Heathers said. “Deliveries have been ongoing.”
Boeing must also determine if any 777s already in passenger service should be checked.
Heathers said the Boeing investigation continues.
“We’re figuring out why it happened and what we have to do to make sure it doesn’t happen again,” she said.
Separately, the FAA’s Kenitzer said that an earlier review of manufacturing procedures at Boeing’s factories in Renton and Everett is still going on a month after it started.
That review came after metal shavings were discovered inside the fuel tank of a new Japan Airlines (JAL) 767 passenger jet during ground maintenance in April.
The FAA is looking at Boeing’s procedures for preventing what the industry calls FOD, or Foreign Object Debris, meaning any material or object that isn’t supposed to be on the airplane when it leaves the factory.
Both the FOD review and the inquiry into the landing-gear incident are “active issues” said Kenitzer.
“We have follow-up investigations under way,” he said.
Dominic Gates: 206-464-2963 or firstname.lastname@example.org