This handbook contains general guidelines for electronic equipment for operation in piloted aircraft and helicopters, missiles, boosters and allied vehicles. Detail electrical and mechanical design, performance and test requirements should be as specified in the detail specification or contract. This handbook is for guidance only. This handbook cannot be cited as a requirement. If it is, the contractor does not have to comply.
This handbook should not be invoked on a blanket basis; however, each guideline should be assessed in terms of need. This handbook is a compendium of general guidelines, the majority of which have been selected from MIL-HDBK-454, for specific applicability to airborne electronic equipment. Individual detail specifications or contract should invoke only those requirements which are applicable and necessary to that specific equipment.
A tailoring guide, Appendix B, is included to assist the acquisition activity and the contractor in applying MIL-HDBK-5400 guidelines to the various phases of equipment design, development and production.
Suggested classification for design and manufacture of electronic equipment is as follows (see 6.2).
Class 1 - Equipment designed for 15.20 km (50,000 feet) altitude and continuous sea level operation over the temperature range of −54° to +55°C (+71°C intermittent operation).
Class 1A- Equipment designed for 9.12 km (30,000 feet) altitude and continuous sea level operation over the temperature range of −54° to +55°C (+71°C intermittent operation).
Class 1B- Equipment designed for 4.56 km (15,000 feet) altitude and continuous sea level operation over the temperature range of −40° to +55°C (+71°C intermittent operation).
Class 2 - Equipment designed for 21.28 km (70,000 feet) altitude and continuous sea level operation over the temperature range of −54° to +71°C (+95°C intermittent operation).
Class 3 - Equipment designed for 30.40 km (100,000 feet) altitude and continuous sea level operation over the temperature range of −54° to +95°C (+125°C intermittent operation).
Class 4 - Equipment designed for 30.40 km (100,000 feet) altitude and continuous sea level operation over the temperature range of −54° to +125°C (+150°C intermittent operation).
Class 5 - Equipment designed for altitudes greater than 30.40 km (100,000 feet) for periods of time not exceeding 6 hours and continuous sea level operation over the temperature range of −54° to +95°C (+125°C intermittent operation).
The addition of the letter "X" after the class number, e.g., (Class 2X), will identify the equipment as operating in the ambient environment of that class, but requiring cooling from a source external of the equipment.
THIS APPENDIX IS NOT A MANDATORY PART OF THIS HANDBOOK. THE INFORMATION CONTAINED HEREIN IS INTENDED FOR GUIDANCE.
This appendix lists specifications, standards, handbooks and other publications selected for their applicability in the design and construction of airborne electronic equipment. Those parts and materials covered by documents listed in this appendix will be considered standard items. When part selection standards are referenced, the documents listed in the selection standard have the same status as those listed directly in this appendix and the parts they cover are also considered standard (unless otherwise restricted or banned for airborne applications).
When Appendix A does not provide a document suitable for the design requirement, selection of specifications and standards for nonstandard parts and materials should be specified by the contracting or design activity, unless otherwise cited herein or in the referenced MIL-HDBK-454 guidelines. Intended Use: This handbook is intended as a general design guide for use in the development and preparation of detail specifications and contracts for airborne electronic equipment to specify those requirements applicable to the specific equipment.