User:RepublicUSAir/MetroJet Flight 2710

MetroJet Flight 2710 was a regularly scheduled flight from Orlando International Airport in Orlando, Florida to Bradley International Airport near Hartford, Connecticut. The flight experienced uncommanded rudder movement on February 23 1999 while flying over Maryland at 33,000 feet, and successfully landed at Baltimore-Washington International Thurgood Marshall Airport in Maryland. This incident is notable because of its similarities to other Boeing 737 rudder issues, and that in this case the rudder moved slowly to its blowdown limit in contrast to the sudden hardover experienced by USAir Flight 427.

Incident
At approximately 11:15 a.m., while flying over Salisbury, Maryland, the Boeing 737-2B7 experienced an unintended wheel deflection while on autopilot and cruising at about 260 knots.  The pilots noticed the control wheel turn to the left, and quickly realized that the autopilot was turning the wheel to counteract rudder movement despite the rudder pedals having not been touched. The first officer discovered that the pedals were displaced to the right, so he disengaged the autopilot and pushed the left pedal to return the rudder to the center position. The pedals did not respond and seemed to be jammed. The pilots immediately followed an emergency procedure that had been created after the crash of USAir Flight 427. They disengaged the yaw damper and activated a standby rudder system that utilizes a backup hydraulic valve; the rudder pedals then moved back to center. After declaring an emergency and informing the passengers of the flight control problem, the pilots diverted the aircraft to Baltimore and landed without incident at 11:30 a.m.

Investigation
Preliminary results of kinematic analysis and computer simulations using data from the flight data recorder indicated that the rudder moved slowly to its blowdown limit. Examinations of the rudder system did not reveal evidence of a servo valve failure or jam or any other malfunction that would explain the sudden rudder hardover. A final report on what caused the incident has not been released.