Summary
The FAA proposes to supersede an existing airworthiness directive (AD) that applies to all Airbus Model A300 B2 and B4 series airplanes; Model A300-600 series airplanes; and Model A310 series airplanes. The existing AD currently requires, among other actions, repetitive tests to detect desynchronization of the rudder servo actuators, and adjustment or replacement of the spring rods of the rudder servo actuators, if necessary. This proposed AD would require new repetitive tests/inspections/analyses of the rudder servo actuators, and related investigative/corrective actions if necessary. Accomplishment of the new actions ends the existing repetitive requirements. This proposed AD is prompted by new reports of desynchronization of the rudder servo actuators. We are proposing this AD to prevent desynchronization of one of the three rudder servo actuators, which, if combined with an engine failure could result in the loss of the related hydraulic system and could cause the loss ofone of the two synchronized actuators. This condition could create additional fatigue loading and possible cracking on the attachment fittings and could result in the inability of the remaining synchronized actuator to maintain the commanded rudder deflection, which could result in reduced controllability of the airplane.