Aerospace Turbine Rotables (ATR) has enhanced the overhaul process for the hydraulic Prestolite Power Pack that it manufactures and which is used on a variety of general aviation aircraft. The Wichita-based subsidiary of First Aviation Services said the new process increases the reliability of the power pack.

Specifically, the overhaul includes replacing the motor’s armature and field coils as well as valves, springs, gaskets, O-rings, pressure adjusting screws, and eyelets. In addition, each motor goes through a qualification analysis, and other components are inspected for wear or damage and replaced if needed.

All the replacement components are manufactured to original engineering specifications. That excludes the valve body, new castings for which ATR has developed to updated standards, and engineering with stricter tolerances.

“The testing that we’re subjecting the Prestolite Power Packs to is well beyond anything we should see in operation, ensuring reliable service for many years,” said ATR assistant shop manager Jeff Horner. “The feedback we’re receiving from operators is that these extensive enhancements have had a major positive impact on reliability.”