MIL-HDBK-274 Electrical Grounding For Aircraft SafetyThis handbook has been prepared to provide U.S. Navy and Marine Corps aircraft maintenance and operations personnel with the background and technical details of the different types of aircraft grounds and how they are applied. In addition, this handbook provides background information for aircraft grounding, static electricity theory and how it affects aircraft, and techniques used for measurement of grounding points. This handbook is intended for use by all U.S. Navy and Marine Corps aircraft maintenance and operations personnel for the purposes of ensuring that aircraft are properly and safely grounded. This handbook is for guidance only and cannot be cited as a requirement.

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5.11.2 Ordnance loading/downloading. Personnel injury or death may result from the inadvertent discharge of explosive devices.  No electrical power transient should be applied to the aircraft during ordnance loading/downloading evolutions per NAVSEA OP 4 and NAVSEA OP 5.

5.11.3 Aircraft ground connections.  The grounding matrices in Tables VI and VII are intended as a quick reference guide for general aircraft grounding.  Refer to the U.S. Navy and Marine Corps Aircraft Naval Air Training and Operating Procedures Standardization (NATOPS) Flight Manual and Maintenance Instruction Manual (MIM) for detailed procedures and specific aircraft ground point locations.  Aircraft NATOPS Flight Manual, MIM or operations manual direction will take precedence over this document in the event of a conflict.

5.11.3.1  Failure to ground. Failure to ground to a designated certified power ground, when necessary, may result in generating a charge potential, if discharged,  and could result in personnel injury or death.

5.11.3.2 Aircraft tie-down chains. Aircraft tie-down chains do NOT provide an appropriate static ground.  For ordnance loading/downloading and aircraft fueling/de-fueling evolutions, a separate grounding cable should be used to connect the aircraft to an approved grounding point.  If an approved grounding point is not available, then the deck padeye is an acceptable static ground if metal-to-metal contact is ensured by grinding the teeth of the ground clamp into the padeye to ensure paint is not impeding the ground to padeye connection.

5.12  Shore-based grounding guidelines. Table VI outlines standard grounding guidelines for aircraft during shore-based operations.  An "X "indicates the appropriate aircraft grounding methods; flight line, hangar or Forward Arming and Refueling Point (FARP) designated grounding point for the corresponding aircraft operation.

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