Case Study – Air Force

We designed an air data calibrator, a piece of portable flight line test equipment that is continually being moved around and must withstand an immense amount of physical abuse by the Air Force. Seven hundred units were to be provided to the government, so we were under severe pressure to keep the recurring costs low.

The unit had to operate reliably with severe environmental requirements which included 300 volts per meter EMI field strength, a 36 inch drop on all corners, faces and edges, and withstand salt spray, jet fuel and an explosive atmosphere.

These requirements forced us to use conductive cooling and a sealed chassis with no external openings. The large 1 x 1 x 2 foot cast aluminum box we designed enclosed pressure vacuum pumps, filters, a pressure source, pressure bottles and control electronics that weighed 125 pounds.

Our design incorporated mounting all heat producing components to the interior walls of the chassis and utilized fins on the exterior to provide convective cooling and to add structural stiffness to the enclosure. The removable top and bottom covers were secured with draw latches for easy access. We also incorporated features that provided mechanical cover/chassis interlocks so that if the unit was dropped, the top and bottom covers would not sheer off.