757 & A321 CARGO DOOR CONVERSION HYDRAULICS
In 2006, Kawak Aviation was contracted by Precision Aircraft Solutions of Beaverton, Oregon to help optimize their cargo door conversion for Boeing 757-200 jets which are converted for use as cargo freighters. The large cargo doors installed into the forward section of the aircraft and are operated by a Kawak hydraulic power module and components for vent, lock, latch and lift operations.
The original design of the door hydraulic system utilized components that were soon discontinued by the original manufacturer, it was at this point that Kawak was contracted to analyze the current valves and subsequently create a drop-in replacement which would not only replace the discontinued part but out-perform it as well. A unique design constraint for the program was that the entire hydraulic system operates on Phosphate-Ester hydraulic fluid which is commonly used on late-model aircraft for its reduced flammability properties. Phosphate-Ester fluid is extremely corrosive and requires special design considerations to resist breakdown effects from the fluid. Following detail component engineering and prototype manufacturing Kawak performed an extensive DO-160 program verifying the hydraulic module and components. This program was initiated and completed with all testing and FAA certification in less than 12 months. Ongoing system review and testing ultimately lead Precision Aircraft Solutions to award an additional contract to design additional valving which would improve function and reliability of the system as a whole.
Kawak continues to support Precision Aircraft Solutions with additional system engineering, testing, and manufacturing. In april of 2021 Precision Aircraft Solutions was awarded FAA Supplemental Type Certificate Number ST02716SE to the group’s new A321-200PCF freighter. Kawak supported this program by Engineering a “like-type” hydraulic system and components to the 757 program. Kawak continues to provide engineering support for the A321 cargo door conversion program and manufactures all hydraulic system and component parts for conversions.
To view more information on the Precision Aircraft Solutions conversion programs follow these links to the B757-200 or A321-200 cargo door conversions.