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

NWP 4-01.43. When ships are yawing excessively, distance betweenships should be near the maximum limit.4. When all transfer stations are located on the quarterof a large ship, distance between ships shouldbe near the upper limit of the normal interval. (Thisis due to the forces that tend to draw the ships together.It is of particular importance when the shipalongside is a destroyer or other small unit.)5. When using a Burton rig, the strain on thewinches will be greater at wider distances betweenships.6. Since transfer rate is directly proportional to distancebetween ships, replenishing near the maximumlimit will take much longer thanreplenishing near the lower limit.2.2.6 Maintaining Station. Maintaining stationalongside the control ship requires precise maneuveringby the approach ship. Steaming too far apart willput an undue strain on the transfer rigs. Steaming tooclose will restrict maneuverability and increase the turbulencebetween the ships. With some loaded oilers,turbulence can throw seas into the tank deck and endangerpersonnel who must work there. Steaming too closewhen using tension/detension rigs will increase theprobability of a collision. Refer to paragraph 2.2.5 andFigure 2-3 for minimum safe distances between ships.2.2.7 Pressure Effects. A ship underway createsa hull wash (Figure 2-4a). There are areas of increasedwater pressure at the bow and stern and areas of decreasedwater pressure (suction) amidships. This venturieffect results from the differences in velocity in theflow of water around the hull.When ships are underway alongside, the venturieffect is increased. It is complicated further by the interminglingof the pressure areas. Pressure effects varywith distance between ships, size and configuration ofships, replenishment speed, and depth of the water.When ships of the same size are alongside, the bestposition is exactly abeam. If the approach ship is considerablysmaller than the control ship, the best positionis in between the bow and stern pressure areas.Figure 2-4b shows ships that are in dangerous positions,because they are being acted on by radically differentpressures. A change in relative position willimpose rapid changes in the pressure effects on theirhulls. Either position may require quick rudder actionby the smaller ship. The hazard is increased when speedis reduced. A radical speed change will further aggravatethe situation.Replenishment operations usually are conducted inrelatively deep water. In shallow water, where pressureeffects are more pronounced, extra care is requiredwhile maneuvering.CAUTIONExcept in wartime or in an emergency, shipswill not operate underway alongside unlessthe depth of the water is at least three timesthe draft of the ship with the greatest draft.aPRESSURE AREASUCTIONAREASUCTIONAREAb2.2.8 Steering Control. The following requirementspertain to steering control during a replenishmentoperation:1. Prior to going alongside, check steering control inall modes of operation, in accordance with applicablePMS, from both the pilot house and aftersteering. Determine gyro error and the operabilityof the standby gyro and associated alarms.PRESSURE AREAFigure 2-4. Dangers of Hull Wash2. Whenever feasible, assign a commissioned line officeras ship control safety officer on the bridge.Whether or not a regularly assigned OOD/JOOD,the ship control safety officer must have completedPQS and demonstrated proficiency to thecommanding officer or his designated representative,prior to assignment. The ship control safetyofficer shall ensure that steering control stationpersonnel acknowledge and comply with all2-8 ORIGINAL