775635-5 — Air Cycle Machine Repair & Overhaul

Component Overview

An air cycle machine (ACM) is the rotating heart of an air cycle refrigeration pack in the environmental control system, mounted downstream of the bleed-air heat exchangers. It typically integrates a centrifugal compressor and an expansion turbine on a common shaft, with the turbine extracting energy from pressurized bleed air and dropping its temperature sharply to condition cabin and avionics air. The shaft rides on air-bearing or oil-lubricated journal and thrust bearings that demand precise tolerances and balance. Service drives overhaul because high rotational speeds and thermal cycling produce bearing wear, shaft scoring, foil-bearing fatigue, seal leakage, blade erosion, and rotor imbalance. Inspection commonly reveals coking, corrosion, and clearance loss, all of which degrade pressure ratio and cooling capacity until restoration is required.

Aircraft Application

Part number 775635-5 (Air Cycle Machine) is installed on the Beech 1900. QTC supports operators and MROs servicing this platform with certified repair and overhaul.

Our Repair Capability

QTC repairs and overhauls 775635-5 to the original manufacturer's specifications under our FAA and EASA Part 145 approvals. Our team — including former OEM air cycle engineers — performs teardown, inspection, cleaning, component replacement, functional testing, and certification, returning a serviceable unit with the appropriate airworthiness release. We also develop repairs for rejected and beyond-economic-repair (BER) hardware.

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Related Parts

Other air cycle machine part numbers we repair — view all Air Cycle Machine parts →

Frequently Asked Questions