The key source of qualitative design feedback is the fleet avionic maintenance technician. The maintenance technician is now aware of problems relating to C/F/M and is an excellent source for qualitative input relating to new design. Steps are being taken at all levels of maintenance to attempt to combat the problems through the use of state-of-the-art maintenance procedures, materials, tools and equipment for cleaning and preservation of all types of avionic equipment. Information on equipment problems recognized by the technicians generally are not documented, but are acquired by on-site visitation and interviews. He is the customer who knows the equipment best.
FLEET CORROSION PROGRAM
The avionic maintenance technician had long been faced with repair and replacement requirements due to corrosion, but it was not until the mid-1970s that the need to train and equip maintenance personnel for their particular encounters with corrosion became a recognized requirement. Toward that end, the NAVAIR 16-1-540 "Avionic Cleaning and Corrosion Prevention/Control" Manual11 was issued. This manual provides the maintenance technician with a better understanding of corrosion as it relates to his specific type of avionic equipment, and it identifies materials and procedures for cleaning, corrosion removal, repair and corrosion prevention.
FLEET MAINTENANCE REQUIREMENTS
In 1978, a test program was established at the IMA at NAS Whidbey Island, WA, to evaluate the possibility of cleaning avionic equipment through the use of mechanical cleaning equipment, solvent and aqueous ultrasonic cleaning equipment, aqueous spray booths, and various types of drying ovens. In one part of the evaluation, 160 items were inducted into the prototype cleaning facility after bench verification of a non-RFI (Ready-For-Issue) condition. Following cleaning and drying, 50% of the non-RFI items were found to be RFI upon subsequent bench check.12 From the foregoing, it would appear that clearly a very significant portion of the avionic equipment removed from service for cause at that facility could be returned to RFI condition by virtue of cleaning alone. This program was the first indication of the significance of the cleanable films as a cause of failures. First hand reports from fleet maintenance technicians of corrosion found on disassembled avionic equipment verify that C/F/M related problems are a major cause of avionic equipment reliability degradation in service.
FLEET MAINTENANCE IMPACT ON NEW DESIGN
The NAVAIR 16-1-540, "Avionic Cleaning and Corrosion Prevention/Control" Manual, has become the maintenance technicians"'corrosion control bible" and should be reviewed by the design engineer. In reviewing this document, the design engineer should give consideration to the cleaning and preservation procedures and techniques being used by maintenance technicians. Granted, design to facilitate these maintenance functions is not presently a formal requirement, but the design engineer should be aware of the possible impact these maintenance functions may have on new equipment design. Clearly, maintenance practices and equipment design must be compatible.