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

NWP 4-01.4NoteAOE-6 Class ships use a unique RCC drivewith fixed pitch propellers instead ofcontrollable pitch propellers to achievespeeds less than about 12 knots. Shipsshould be in direct drive, which bypassesthe RCC, for maximum maneuverabilityduring underway replenishments.2.2.3 Approach Procedures1. The control ship, when ready to receive a shipalongside, hoists ROMEO close up (see Figure2-2). At night, ROMEO close up must be signaledby flashing light.2. The approach ship, when ready for UNREP at thedesignated stations, commences the approach andhoists ROMEO close up. At night, ROMEO closeup must be signaled by flashing light.3. The approach ship slows, so as to be moving atreplenishment speed when in position alongside.(Use of high approach speeds and/or backingbells is permissible, but only if weather conditionsare favorable and personnel are proficient.)4. The conning officer on the bridge of the approachship attains proper fore-and-aft position alongsideby observing the appropriate ship structureor the station-keeping aid on the control ship.Appendix K provides additional information andillustrations of the station-keeping aid.5. When both ships are in the proper relative position,the lines are passed. Both ships haul downROMEO when the first messenger is in hand onthe receiving ship.2.2.4 Lateral Separation. The approach ship mustensure adequate lateral separation during the approach,particularly when its bow passes the control ship’s stern.There is a risk of collision at this stage, unless lateral separationis adequate. The differential in water pressure cancause the approach ship’s bow to veer in toward the controlship. Relative speed should be reduced when replenishingin shallow water. Shallow water increases theeffect of the differential in water pressure. Adequate lateralseparation is vital at night and during periods of poorvisibility when depth perception is impaired.When steering by magnetic compass, the approachship must make a wider approach than would normallybe required using the gyrocompass. Conning officersand helmsmen must be alert for the swing of the magneticcompass toward the other ship. The swing occurswhile the approach ship is coming alongside.2.2.5 Distance Between Ships. The approachship must maintain station at a sufficient distance fromthe control ship to ensure that the replenishment can beaccomplished safely and efficiently. The proper distancebetween ships depends on several factors:1. Wind and sea conditions2. Sizes and types of ships3. Ability of ships to maneuver while alongside4. Types of transfer rigs employed5. Depth of the water6. Replenishment speed.Figure 2-3 provides the distances between ships forthe transfer rigs in use. The following guidelines applyto the information in the table:1. Optimum distance between ships normally lies betweenthe upper and lower limits of the normal interval.2. Minimum safe distance between ships is thelower limit of the normal interval.3. When tensioned and nontensioned rigs are usedtogether, the distance between ships should notexceed that specified for the nontensioned rig.CAUTIONShips that have protrusions that extendoutward from the hull must measure thedistance between ships from the outermostprotrusion, perpendicular to the centerline.Certain operational considerations have an effect onthe distance between ships:1. When replenishing in water of less than 35 fathoms(64 m), increase the distance between shipsas the depth of the water decreases.2. Increase the distance between ships as replenishmentspeed increases. At a speed of 15 knotsor more, distance between ships should be nearthe maximum limit.2-5 ORIGINAL