Each enclosure had to be light weight and support several hundred pounds of commercial electronic equipment, yet survive crash safety and protect the electronics from the low level vibration of the helicopter.
Each cabinet was four feet tall and two feet deep, the left one four feet wide and the other two feet wide. We elected to use a custom machined base and top plate with thin riveted aluminum sheet metal sides to keep the weight within acceptable limits.
The two cabinets sit near the engine in an extreme heat area. Both cabinets were designed to use heat exchangers, interior thermal insulation blankets and high impedance fans to circulate the cooling air. Each cabinet had to be designed to accommodate approximately 600 pounds of rack mounted commercial radar electronics mounted to an internal frame. The frame was shock isolated to the top and bottom cabinet structure with Aeroflex isolators.
The design had to meet twenty “g” crash safety and airworthiness stress analysis. The electronics also needed to operate reliably in the low frequency random vibration environment of a helicopter.
Due the aggressive schedule, our client elected not to perform any environmental testing and the units worked right the first time they were flown.