San Francisco, September 26 (Xinhua) -- The National Transportation Safety Board of the United States has issued emergency safety recommendations to Boeing and the Federal Aviation Administration on the 26th to address the issue of possible jamming or restriction in the rudder control system of some Boeing 737 models.
On February 6th, a Boeing 737-8 (MAX model) aircraft operated by United Airlines landed at Newark Liberty International Airport in New Jersey. While taxiing on the runway, the rudder pedal got stuck. The captain operated the aircraft through the rudder in the cockpit, and all 155 passengers and 6 crew members on board were unharmed.
Boeing aircraft component supplier Collins Aerospace has confirmed that during the production process of rudder actuators, incorrect assembly of sealed bearings can easily cause moisture, leading to icing and limiting the rudder system. Since February 2017, Collins has delivered at least 353 problematic components to Boeing and installed them on some Boeing 737NG and 737MAX models.
The National Transportation Safety Board stated in a statement that the rudder actuator is located at the tail of the aircraft and is designed to control the rudder during approach, landing, and taxiing. The Boeing 737 flight manual instructs pilots to apply maximum force to overcome a rudder jam or restriction. But the National Transportation Safety Board of the United States is concerned that applying such a large force during landing or taxiing operations may cause excessive force on the rudder pedal, causing the rudder to suddenly move, resulting in the aircraft losing control or deviating from the runway.
The National Transportation Safety Board of the United States recommends that Boeing revise its flight manual and remove the recommendation for pilots to use maximum pedal force to control a stuck rudder. The committee also recommends that the Federal Aviation Administration of the United States decide whether to remove problematic components from the aircraft. If the Federal Aviation Administration of the United States determines that the affected components should be removed, it should also notify aviation regulatory agencies in other countries.