MIL-HDBK-274A
4.4.2.2.4 Defective cables. Since many electrical problems are caused by defective cable plugs, it is imperative that cable plugs be carefully and frequently examined for bare or broken wires, or other damage prior to connection to the aircraft. It is also extremely important that the cable and connector be thoroughly checked and tested after repair and before being returned to service. The U.S. Navy Support Equipment, Basic Handling and Safety Manual, NAVAIR 00-
80T-96, paragraph 3-3200, addresses the hazards of electric shock associated with defective electrical cables and connectors.
4.4.2.2.5 Deck edge power. Deck edge power supplied by the ship's electrical system is not grounded to the ship's structure. The neutral of the 3-phase power is not tied to the ship's structure and therefore the system represents a floating neutral power source.
4.4.2.3 RF electromagnetic energy. Today's environment has many unintended side effects caused by radio frequency transmitting devices used in conjunction with naval flight operations. Of concern are those high power communication and radar transmitters that may be located near parked aircraft. The best example of this situation is the aircraft carrier flight deck, which probably contains the highest concentration of transmitted RF energy to be found on any base from which aircraft operate. Although high power communication and radar transmitters may be found at greater distances from parked aircraft at a shore station, an aircraft may be affected by any adjacent aircraft whose onboard communication system or radar transmitters are being tested. Aircraft aboard ship could be similarly affected.
4.4.2.3.1 Amount of RF energy. The principal problem is the amount of RF energy induced into the aircraft frame and circulating on the aircraft skin. This quantity or level of RF energy is greatly affected by the position of the aircraft relative to a particular RF transmitter, the power output of the transmitter and the actual frequency of the RF energy being transmitted. It is further affected by the actual location of any connections between aircraft and ground (deck). Where position of one ground may have a significant effect on induced current, other ground connections from different locations on the aircraft to other locations on the deck may not have the same effect. Any existing aircraft grounding scheme should not be altered in an effort to provide the aircraft with additional protection against RF energy. If the ground connection is broken while the RF transmission is in progress, an electric arc may be drawn. This is an important fact to note. If an arc is produced while disconnecting a ground, the source may be RF energy, caused by a local transmitter and the current flow can be high. (A power line short
circuit to ground may also produce an arc when the ground is disconnected.) If, on the other hand, an arc is drawn while a ground is being attached to the aircraft, the source is static electricity and the current flow will be light.
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