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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Earth ground.

3. A Certified Power Ground will have a current certification (dated within a 24-month period) and be labeled with resistance values of less than 25 ohms referenced to the power system neutral (Ref NAVSEA OP 5, Chapter 5).

4. When a MEPP is utilized, a grounding cable must be attached from the MEPP to the aircraft airframe (Ref NATOPS Flight Manual/ MIM).

5. FLEDS operations also recommend grounding of the aircraft airframe to the FLEDS

earth neutral.

6. Grounding triangulation (fuel delivery system bonded to aircraft and aircraft grounded to static ground) is recommended during fueling/defueling operations (Ref NATOPS Flight Manual/ MIM)

7. Refer to Aircraft NATOPS Flight Manual and Aircraft Refueling NATOPS Manual

(Ref. NAVAIR 00-80T-109, Chapter 16)