Actuators Repair & Overhaul

Actuators convert electrical, pneumatic, or hydraulic input into the controlled mechanical motion that drives aircraft systems. They position and move flight and system hardware on demand, from a horizontal stabilizer actuator that trims the aircraft, to a DC rotary actuator or general actuator assembly driving a valve or mechanism, to a landing light actuator that extends and retracts a lamp. Related driveline hardware such as flexible shaft assemblies transmits that motion to the load, and sequence timers like a horizontal stabilizer de-ice sequence timer coordinate when actuation occurs.

Electromechanical actuators pair a motor with a gear train, and often a clutch, brake, or position-feedback device, to produce precise rotary or linear travel. Hydromechanical units use fluid pressure acting on a piston or rotary element, regulated by internal valving, to develop high force in a compact package. In every case the device must deliver the correct travel and torque, hold position, and respond predictably to command.

Wear is the principal driver for overhaul. Gear teeth, bearings, and bushings wear and develop backlash, motor brushes and windings degrade, clutches and brakes lose grip, and seals on hydromechanical units fatigue and leak. These conditions show up as lost travel, reduced output torque, slow or erratic response, or internal leakage. Repair and overhaul replace the worn mechanical and sealing elements and re-establish the unit's rated travel and torque performance.

QTC overhauls actuators and their associated driveline components within its Part 145 scope. Each unit is functionally tested as received, then fully disassembled so gears, bearings, bushings, motors, clutches, brakes, and seals can be inspected and measured. Worn or out-of-tolerance components and fatigued seals are replaced, parts are cleaned and inspected for wear, corrosion, and damage, and the unit is reassembled and rigged to its required backlash and clearances.

The rebuilt actuator is then functionally tested against its specification. Travel, torque-versus-travel, and rate are verified, position feedback and limit/sequence functions are checked, and hydromechanical units are run and leak-checked across their operating range. Once the unit meets its travel, torque, and functional requirements, it is certified and returned to service with the appropriate airworthiness documentation.