Compressor Section
Draws in and compresses air for combustion. Inspection, blade replacement, balancing and case repair.
APU Overhaul, Repair & Maintenance
Auxiliary Power Unit MRO across all major sections, compressor, combustion, turbine, load compressor and accessory gearbox. Performed in-house under FAA & EASA Part 145 authority.
APU Core Components
From core sections to accessories
A small gas turbine engine that provides electrical power and pneumatic (bleed) air to the aircraft when the main engines are not running.
Combustion Chamber
Where fuel and air mix and ignite. Liner inspection, fuel-nozzle servicing, ignition system check.
Turbine Section
Converts hot-gas energy into mechanical power. Blade NDT, nozzle vane repair, shaft balancing.
Load Compressor
Supplies bleed air for engine start and air conditioning. Overhaul, surge valve service.
Generator
Converts APU mechanical energy into electrical power. Brush gear, bearings, BIT system test.
Starter Motor
Spins the APU to self-sustaining speed. Brush replacement, commutator turning, full functional test.
Auxiliary Systems
Fuel, lubrication, air & electrical
Every supporting system fully overhauled with calibrated test stands.
Fuel & Control
- Fuel Control Unit (FCU)
- Fuel pump & pressure regulator
- Fuel nozzles & manifold
- Fuel scheduling calibration
Lubrication
- Oil pump rebuild
- Oil filter & bypass
- Oil cooler service
- Bearing & gear inspection
Air & Exhaust
- Bleed air valve overhaul
- Surge bleed valve
- Exhaust duct inspection
- Plenum gasket service
Electrical & Control
- ECU / control box
- Wiring harness inspection
- Ignition exciter test
- BIT functional verification
Sensors & Monitoring
- EGT (Exhaust Gas Temperature)
- Speed (RPM) sensor
- Oil pressure & temperature
- Air-system pressure switches
Accessory Gearbox
- Gear set inspection
- Shaft NDT
- Seal replacement
- Pad-mount accessory test
Fault Diagnosis
Common APU faults we resolve
Decades of fleet-wide experience translate into rapid root-cause analysis and dependable returns to service.
Hot Start
Excessive EGT during start-up, typically traced to fuel-scheduling, ignition timing or compressor stall. We diagnose, correct & verify.
Hung Start
APU fails to accelerate to self-sustaining speed, starter, ignition, fuel-flow or compressor surge investigations.
Overspeed Events
RPM exceeds safe limits, governor verification, FCU test, full functional re-validation prior to release.
Oil System Faults
Oil consumption, contamination or pressure drops, pump, cooler, seal & bearing investigation.
Bleed Air Loss
Insufficient or unstable bleed pressure, surge valve, load compressor & ducting integrity checks.
Electrical Output Issues
Generator output low, fluctuating or absent, brush, bearing, rectifier & control box rebuild.
Reduce APU downtime
Maximize availability with a partner who lives APUs
Send us your APU and we'll deliver an overhauled, fully tested asset on a predictable schedule.