Boeing blames missing paperwork for Alaska Air incident, prompting NTSB reprimand

Renton, Washington
CNN
—

Missing documents on a 737 MAX plane that lost its door seal on an Alaska Airlines flight in January not only make it difficult to figure out who made this tragic mistake. Boeing revealed this week that the documents may have caused the problem in the first place.

It was already known that no documents had been found showing who worked on the door plug. What was revealed this week at a press conference at Boeing's 737 MAX factory in Renton, Washington, is that a lack of paperwork is the reason the four screws needed to hold the door plug in place were not installed before the plane left the factory in October. Workers who needed to reinstall bolts never had a work order telling them what work needed to be done.

Without the screws, the door seal mishap was pretty much inevitable. Fortunately, it was not fatal.

It’s a sign of quality problems along Boeing’s assembly lines, the focus of several federal investigations and whistleblower revelations, and the cause of delays in aircraft deliveries that are causing headaches for airlines and passengers around the world.

But Boeing may have gotten itself into more trouble with regulators by revealing details at this stage. The National Transportation Safety Board (NTSB) rebuked Boeing on Thursday for releasing “non-public investigative information” to the media. It said in a statement that the company “blatantly violated” the agency's rules.

“During a press conference Tuesday about quality improvements…a Boeing executive provided investigative information and provided analysis of previously released factual information. “Both actions are prohibited,” the NTSB said.

The agency said Boeing will no longer have access to information generated by the National Transportation Safety Board during the investigation, adding that it is referring Boeing's conduct to the Justice Department.

“As a party to numerous NTSB investigations over the past decades, there are few entities that know the rules better than Boeing,” the NTSB said.

Boeing did not immediately respond to CNN's request for comment outside normal business hours.

During Tuesday's briefing, Boeing said the problem with the door seal on the Alaska Air plane occurred because two different sets of employees at the plant were assigned to do the work, with the first group removing the door seal and the second group reinstalling it as the plane passed along the assembly line. .

The first group of employees removed the door seal to address issues with some bolts manufactured by the supplier, Spirit AeroSystems. But they did not create paperwork indicating that they removed the door plug, as well as the four screws needed to hold it in place, in order to do the work.

When a different group of employees put the plug back in place, Boeing said they did not think the plane would actually fly in this condition.

Instead, they would just plug the hole with caulk to protect the inside of the fuselage from the weather while the plane was moving out. This group of employees often does this type of temporary repair.

“The door team closes the plane before transporting it outside, but it is not their responsibility to install the bolts,” said Elizabeth Lund, senior vice president of quality for Boeing's commercial aircraft unit.

These employees will likely assume that there is paperwork proving that the plug and screws have been removed, and that this paperwork will prompt someone else down the line to install the screws.

But without the paperwork, no one elsewhere on the assembly line would have known that the door plug had been removed, or that its screws were missing, Lund said. Removing the door seal after the plane arrives from Spirit AeroSystems rarely happens, Lund added. So no one was aware that the door plug needed attention.

“The (permanent) reinstallation process is performed by another team based on paperwork showing incomplete tasks,” Lund said. “But there were no papers, so no one knew to follow up.”

In fact, the plane flew for about two months with the door plug in place even though there were no screws. But minutes after an Alaska Airlines flight took off from Portland, Oregon, on January 5, the door plug exploded, leaving a gaping hole in the side of the plane. The passengers' clothes and phones were snatched from them and sent hurtling into the night sky. Fortunately, none of the passengers were seriously injured, and the crew was able to land the plane safely.

The missing bolts were identified in the National Transportation Safety Board's preliminary findings, but that report did not assess liability for the accident. The final report is not expected to be issued for about a year or more. An NTSB spokesman said the safety agency is continuing its investigation and will not comment on Boeing's explanation of how the error was made.

In February, the committee issued a preliminary report in which it said it discovered that the bolts were missing when they left the Boeing factory, but did not specify who was responsible. The final report is not expected to be issued for a year or more from now.

NTSB Chair Jennifer Homendy has testified about the missing papers at congressional hearings since then.

Lund said Boeing is addressing the problem by reducing the speed at which planes move along assembly lines, making sure planes don't encounter problems on the assumption that those problems will be dealt with later in the assembly process.

“We have slowed down our factories to ensure that the situation is under control,” she said.

“I am very confident that the measures we have taken” will ensure the safety of every aircraft leaving this factory, she added.