Sources Sought: Aircraft Intermittent Fault Operational Environment Stimulation
Intermittent faults are a growing problem and many of the maintenance issues of which repair facilities contend with are directly related to interconnectivity problems on the aircraft Electrical Wiring Interconnect System (EWIS) or within Line Replaceable Unit/ Weapon Replaceable Assembly (LRU/WRA) electronic equipment. Hard failures, where wiring issues are evident, are relatively routine to detect and repair, and not all hard failures involve wiring. However, major electrical issues and even critical down-line failures may occur when an electrical fault appears only intermittently, in short duration, under operational conditions (such as high G-force loading and extremes in temperature or stress, or vibrational states) that are difficult to replicate. These intermittent faults are difficult to identify, isolate, and ultimately repair.
There was no standardized, automated, DOD-approved process to consistently detect these faults. Industry developed Intermittent Fault Detection (IFD) and diagnostic equipment to identify these faults. In addition, this industry development included the integration of the diagnostic equipment with environmental test chambers and vibration tables to simulate the LRU/WRA or EWIS operating environment.
The challenge is environmentally stimulating LRU/WRA or EWIS in the aircraft. Care must be taken to environmentally stimulate LRU/WRA or EWIS, but not damage the aircraft components. In addition, access and space on the aircraft is limited, so that any environmental stimulation must be small and compact. Further consideration must also be given in regard to the Electromagnetic Interference (EMI) and aviation fuel environment of an aircraft.