727494 — Precooler Repair & Overhaul

Component Overview

A precooler is an air-to-air heat exchanger positioned in the engine bleed-air supply, usually in the nacelle or pylon, that cools high-temperature engine bleed air using fan air before it enters the pneumatic distribution system. By lowering bleed-air temperature it protects ducting, valves, and downstream environmental control and anti-ice systems from thermal damage. As a heat transfer component it functions as a compact plate-fin or tubular core exposed to large thermal gradients and pressure differentials. Repair and overhaul are driven by core fouling and clogging, fin erosion, internal and external corrosion, thermal-fatigue cracking of tubes and headers, braze-joint failures, and internal or external leakage that degrade cooling effectiveness and can allow cross-contamination between air streams.

Aircraft Application

Part number 727494 (Precooler) is installed on the Twin Commander. QTC supports operators and MROs servicing this platform with certified repair and overhaul.

Our Repair Capability

QTC repairs and overhauls 727494 to the original manufacturer's specifications under our FAA and EASA Part 145 approvals. Our team — including former OEM heat transfer 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.

View Pre-Coolers capability →

Related Parts

Other precooler part numbers we repair — view all Precooler parts →

Frequently Asked Questions