(The Hill) - The Federal Aviation Administration (FAA) has said an operator of a 737 Max plane discovered loose bolts in a rudder control system for the plane.
The FAA said it received a report about a missing nut, washer and "migrated" bolt in the system from an operator in December of last year.
It said Boeing then inspected all 737 Max 8, 737 Max 8-200, and 737 Max 9 planes in production and turned up another “under-torqued nut at the same location.”
Boeing said in a statement to The Hill on Friday that operators have inspected more than 1,400 737 MAX airplanes since late December and no other airplane was found with the condition that initiated the inspection.
Inspections on related jets have been completed, the company added.
The FAA, meanwhile, said in a statement on Thursday that inspections recommended by Boeing in December had been completed by all U.S. airlines in early January.
“The FAA carefully reviewed the inspection results, which found no missing or loose rudder bolts," the FAA said.
An airworthiness directive from the FAA that will require “a one-time inspection” of the system in which the loose bolts were discovered for certain Max airplanes is scheduled to be published Monday.
The agency’s directive follows last month’s incident in which an “explosive decompression” occurred on an Alaska Airlines 737 Max 9 flight from Portland, Ore., to Ontario, Calif., when a panel plugging an unused emergency exit door blew off during the plane's flight.
An attorney for more than 20 passengers on the Alaska Airlines flight that experienced the blowout said the plane was “essentially a time bomb” in the wake of a National Transportation Safety Board (NTSB) preliminary report that found bolts missing from the plane.
“A plane was delivered by Boeing to Alaska Airlines without four critical bolts, which means the plane was essentially a time bomb. This door plug could have blown off at any time,” attorney Mark Lindquist said to Fox News’s “Fox and Friends.”
The NTSB’s Tuesday report found that the four bolts that secure a door plug on the Max 9 aircraft were missing before it experienced the blowout.
“Overall, the observed damage patterns and absence of contact damage or deformation around holes associated with the vertical movement arrestor bolts and upper guide track bolts in the upper guide fittings, hinge fittings, and recovered aft lower hinge guide fitting indicate that the four bolts that prevent upward movement of the MED [mid exit door] plug were missing before the MED plug moved upward off the stop pads,” the report states.