UNDERWAY REPLENISHMENT NWP 4-01.4 - Historic Naval Ships ...

NWP 4-01.48. Knowledge of shipboard operations9. Knowledge of approved rigging procedures forexternal loads.The landing support detachment of the combat servicesupport element within a MAGTF has the expertiseto assist in training to meet the objectives listedabove. The landing support battalion of the force servicesupport group is also capable of providing trainingto meet these objectives.10.16.6.2 Night Operations. Because of the increaseddifficulty involved in conducting external loadoperations during darkness, extensive training and detailedplanning become increasingly important. Certainproblems will exist at night that do not occur duringdaylight operations. Common difficulties include increasedtime required for hookup, a tendency for thehelicopter to drift during hover, and the lack of depthperception for aircrew and HELT personnel. Short durationchemical lights attached to the top of the load canassist the aircrew in identifying the load; likewise,chemical lights attached to the pendant hook will aidHELT personnel in the hookup operation.10.16.7 Safety. Shipboard helicopter external loadoperations require more preparedness and alertnessfrom personnel than operations ashore because of theincreased hazards. Some of the major hazards to keepin mind include:1. Confined helicopter operating area2. Pitching and rolling decks3. Wet and slippery decks4. Turbulent winds due to ship’s movement andsuperstructure5. Potential of being struck by the helicopter.10.16.7.1 Static Electricity. In flight, a helicoptergenerates and stores a charge of static electricity. Whenthe helicopter lands, this charge is grounded out. However,in flight, the charge remains stored unless a path isprovided for it to be grounded. The CH-53E is the helicopterthat generates the greatest amount of static electricity— up to 200,000 volts on a dry, hot day. Thebuildup of static electricity in all helicopters must beneutralized prior to touching the aircraft’s cargo hook,even if insulated lineman gloves are worn.WARNINGBuildup of static electricity in the helicopter’scargo hook must be grounded beforeattempting hookup with a sling. Contact of thestatic discharge grounding wand with thecargo hook must be maintained continuouslyuntil hookup is complete. Static electricity isdangerous and can cause serious injury ordeath.10.16.7.2 Rotor Downwash. Ground and deckcrew members must be aware of the effects ofdownwash from helicopters, especially the CH-53E.Excessive downwash can cause difficulty for personnelin walking or standing and its force can move unsecuredmaterial. Because the CH-53E provides thegreatest amount of downwash, ground and deck crewmembers who encounter high velocity downwashshould drop to the deck in a sitting or prone position.WARNINGThe greatest downwash velocity occurs from60 to 70 feet (18.3 to 21.3 m) from the cargohook. The CH-53E can generate downwashgreater than 120 knots. Before conduct ofexternal load operations, ground and deckcrews must be briefed on the downwashpotential of the helicopter and safetyconsiderations. Personnel who encounterhigh velocity downwash should drop to thedeck in a sitting or prone position.10.16.7.3 Additional Hazards. The hazards foundin working under a hovering helicopter are not alwaysapparent. In addition to static electricity and rotor downwash,other hazards to consider and avoid include:1. Flying debris and FOD.2. Tangling of cargo slings. This may also causefasteners to disengage, thus increasing the potentialof dropping the load.3. Objects that protrude from loads or the aircraft.4. Top-heavy or unbalanced loads. Load weightshould be verified and the hookup points checkedfor proper distribution of cG.10-36 ORIGINAL