Maneuvering the Sally Maersk

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Voyage Management SystemThe voyage management system is at the top of the automation hierarchy andcompared to the next level down—the auto pilot—the voyage management system isa significantly more complex and flexible system. Steering and speed control are atthe core of both systems—yet the voyage management system works on input from awider selection of sensors and is capable of more refined steering control.Figure 20. Inputs and outputs to the voyage management system.The voyage management system consists of three major units: the voyagemanagement system unit, the conning station (including conning display), and theplaning station. For now we need only notice that the calculations performed by thevoyage management system can be used to steer the vessel because the voyagemanagement system is hooked up to the auto pilot. The voyage management systemcan override the track following performed by the auto pilot. In order to understandthe essence and utility of this particular automation function we need to consider thenavigational aspects in the use of the voyage management system.The passage planThe Sally Mærsk never leaves a harbor without a detailed plan of where to go andhow to get there safely and on time. One does not just head out from A in the generaldirection of B. Every step of the voyage is carefully planned before initiating thevoyage. The document specifying the route to be sailed between two subsequent portsis referred to as the passage plan. The passage plan is provided by the master andcarefully reviewed on board by the navigating crew prior to departure.During the voyage the passage plan (figure 21) is available to the navigators inthree formats: alphanumeric (digital and hard a copy of an Excel spreadsheet,graphical representation in the sea charts, and plotted as a graphical superimpositionon the digital sea charts displayed by the voyage management system.The basic content of a track plan is a list of way points WP defining certainactions—most commonly the position where a course change is to take place. Thecolumns labeled LATITUDE and LONGITUDE specify the geographical position of theway point, the position at which to take action.10
Passage plan: ROTTERDAM DEPARTUREWP Latitude Longitude RL/GL Course Dist. Dist. rem. Notesnm nm52 51°57,80N 004°05,27E RL 83° 1,5 6,3 ROT: 2xspeed53 51°58,58N 004°05.56E RL 12,9° 0,8 5,5 ROT: 2xspeed54 51°59,78N 004°0165E RL 296,4° 2,7 2,855 52°00,80N 003°57,50E RL 291,7° 2,8 0 Mass PilotTotal distance: 7,7 nm.Charts:132-122Radar chart: ROTRadar route: DEPROT2Admiralty list: NP 286/1Figure 21. Passage planPilot information:Mass Pilot / Mass ApproachVHF Channel: 02/01Tide information:See table NP. 201Local phenomena:Consult pilotHave in mind that positions ofbuoys might differ betweenthe chart and the actualpositions.Buoys may be extinguished ormissing—ask Pilot.The column marked COURSE specifies the course to be sailed from the specifiedway point onwards; that is, the course to be sailed in order to arrive at the subsequentway point. Distance (DIST) lists the distance of the present course segment—thedistance to the next course change, and distance remaining (DIST. REM.) shows theremaining distance to be sailed within the present part of the passage plan. Thecategory NOTES can hold different sorts of information of relevance to the navigation.In the presented plan 1 the first two notes specify that the course change—or rather theturn that will take the vessel from one course segment onto the next—should beperformed at a turn rate (measured in degrees per minute) of two times the speed ofthe vessel: if the vessel travels at 10 knots the turn should be performed at a rate of20° per minute.The first column in the lower part of the passage plan shows a list of the sea chartsto be used during the passage; the totality of sea charts needed for a voyage isreferred to as the chart portfolio. The on board radars are capable of superimposingsketched charts of lanes and course lines (called 'nav lines') onto the radar image:ROT and DEPROT2 are the file names of the respective radar chart and route to beloaded while leaving the port of Rotterdam. PILOT INFORMATION lists the name of thetwo pilot services of the Rotterdam harbor, and VHF CHANNELS lists the channels onwhich the pilots can be contacted on the VHF radio. TIDE TABLES play an importantrole in determining the time frame within which the sufficient water depth allowingthe vessel to enter/exit a harbor will be available. Tides should allow for no less thanone meter of water under the keel during navigation in and around the harbor area.While the vessel is moored (made fast) at the quay, the acceptable limit is at 30centimeters. The category labeled LOCAL PHENOMENA may list any peculiarities orspecifics of the present harbor. The third column is another set of general remarks tobe taken into account during the approach.System modesThe voyage plan is keyed into the voyage management system via the planing station.The way point positions can be entered into the voyage management system in twodifferent ways: they can be established by pointing to the position in one of the1The format of the shown passage plan is in accordance with the passage plan used on board the SallyMærsk—only the contents is fictive.11
Page 1 and 2: Maneuvering the Sally MaerskM O R T
Page 3 and 4: MANEUVERING THE SALLY MÆRSKIntrodu
Page 5 and 6: Figure 2. Helm standThe rudder move
Page 7 and 8: Auto PilotThe auto pilot is capable
Page 9: identical function but the limitati
Page 13 and 14: Figure 22: Turning circle for Sally
Page 15 and 16: Figure 25. Main engine telegraph.Ba
Page 17 and 18: Figure 28: The crash astern test.Fi
Page 19: Figure 31: Thruster controls.The th

Maneuvering the Sally Maersk

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