US FAA issues safety alert over Boeing 737 rudder issue

The Federal Aviation Administration said on Tuesday it issued a safety alert to airlines warning of the potential for limited or jammed rudder movement on certain Boeing 737 aeroplanes after a safety official urged the agency to take action.

The National Transportation Safety Board on Sept. 26 issued urgent safety recommendations to Boeing and the FAA after investigating the potential for rudder issues in some 737 planes, which prompted the FAA to convene a corrective action review board.

The NTSB recommendation came as they investigated a February incident involving a United Airlines flight.

The safety alert directs pilots and airline operators to review Boeing's procedure for responding to a jammed rudder. The FAA said it will collect data as a result of the recommended check and investigation but does not plan to propose a directive that would require airlines to replace the parts that can stick.

Last week, the NTSB said more than 40 foreign operators of Boeing 737 aeroplanes may be using 737 or 737 Next Generation planes with rudder components that could pose safety risks.

The FAA said the alert provides information on an existing automated check of the rudder system "that would identify limited or jammed rudder movement during approach prior to landing" and said airlines should warn pilots the rudder "could potentially become jammed or restricted in flight or during landing due to moisture that could accumulate and freeze."

The NTSB said 271 impacted parts may be installed on aircraft in service operated by at least 40 foreign air carriers as well as 16 that may still be installed on US-registered aircraft and up to 75 may have been used in aftermarket installation.

Boeing in August informed affected 737 operators of a "potential condition with the rudder rollout guidance actuator" in what is known as a Multi Operator Message.

Boeing said on Tuesday it continues to work under the oversight of regulators and has "reminded operators of the proper actions that flight crews should take if they encounter rudder restriction."

The NTSB is investigating an incident in February in which the rudder pedals on a United 737 MAX 8 were stuck in the neutral position during a landing at Newark Liberty International Airport in New Jersey. There were no injuries to the 161 passengers and crew.

United said last month the rudder control parts at issue were in use in only nine of its 737 aircraft originally built for other airlines and that the components were all removed earlier this year.

The FAA disclosed on Tuesday that in March, an Aeromexico Boeing 737 MAX experienced a rudder pedal restriction accompanied by a noticeable sound and sensation in the flight deck. Aeromexico did not immediately comment.

The NTSB earlier criticised Boeing for failing to inform United the 737s it received were equipped with actuators "mechanically connected to the rudder control system" and expressed concerns other airlines were unaware of their presence.