FAA tells airlines to check panels on second Boeing plane

The Federal Aviation Administration recommended that airlines late Sunday evening begin visual inspections of door plugs installed on Boeing 737-900ER planes, the second Boeing model to come under scrutiny this month.

The FAA said the plane has the same door plug design as the 737 Max 9, whose fleet's 171 jets were grounded after a door panel blew off one of the jets shortly after an Alaska Airlines flight left Portland, Oregon, on Jan. 1 . 5., forcing an emergency landing.

The door plugs are placed as a panel where there would otherwise be an emergency door if an aircraft had more seats.

The federal Aviation Safety Agency subsequently grounded the 737 Max 9 fleet and announced it was investigating whether Boeing failed to ensure the plane was safe and met the agency's approved design .

The FAA said Sunday that the door plug on the 737-900ER, which is not part of the Boeing Max line, has not yet been a problem.

“As an additional layer of safety, the Federal Aviation Administration recommends that operators of Boeing 737-900ER aircraft visually inspect the center exit plugs to ensure the door is properly secured,” the agency said in a statement.

The FAA recommends that airlines operating the Boeing 737-900ER immediately inspect the four locations used to attach the door plug to the airframe. The Boeing 737-900ER has more than 11 million operating hours and approximately four million flight cycles, according to the FAA

“We fully support the FAA and our customers in this action,” Boeing said in a statement.

Alaska Airlines, United Airlines and Delta Air Lines, which operate the 737-900ER, each said in statements that they had already begun checking their fleet's door plugs. None of them expect any disruptions to their activities.

The incident involving the Alaska Airlines 737 Max 9 flight earlier this month did not result in serious injuries, but it could have been much more serious if it had occurred when the plane was at cruising altitude. The National Transportation Safety Board is investigating the incident in hopes of finding out what caused the door plug to be dislodged from the plane.

In the meantime, the FAA recently ordered an initial round of inspections of 40 of the grounded Boeing 737 Max 9 aircraft as it works to develop final inspection instructions for the planes.