Navigational Watchkeeping

You may remember we talked about Taking Over Navigational Watch at Night in a previous article.  If you missed that article, read it here,
Today we are going to talk about Navigational Watchkeeping, an extension of the same article.
We now turn to the article..



Navigational Watchkeeping



First we will talk about a few things that are common to all types of ships


1. Compare compasses soon after taking over watch. Autopilots usually have a Magnetic Compass Off Course Alarm'. Ensure that it is switched on and check the 'Permissible drift value fed in . If such an alarm is not fitted, compare magnetic and gyro compasses at regular, frequent intervals to check for gyro wander. 

2. Check synchronisation of gyro repeaters at least once a watch. 

3. Fix the position of the ship at frequent, regular intervals. The intervals would be according to the Master's instructions. In coastal waters, it may be 30 minutes, 20 minutes, 15 minutes or even less, depending on the scale of the chart, speed of own ship, proximity of dangers, the current experience- ed. etc. Whenever possible. rely on visual fixes verified by Radar. Decca Navigator, Loran, etc. Do not rely on pasitions obtained by one instrument alone, Compare fixes with DR positions and obtain the set and rate of current. 

4. Check compass error as soon as reasonably possible, after taking over watch. Thereafter, if practicable, check compass error every time a major course alteration is made, after the compass has settled. Each time, enter the results in the Compass Error Book (also called Azimuth Book) for future reference. 

5. Before altering course, check the chart once more and verify that the intended course is safe and that its value has been correctiy read off. 

6. Keep a sharp lookout. Periods away from lookout, by the OOW, for any other essential work on the bridge, shouid be never more than 2 or 3 minutes at a time. 

7. Inspect the 'Navigation Light Sentinel' to ensure that each of the necessary navigation light bulbs are agiow Recheck at least once every half-hour. Once in a watch, check that the audible failure alarm' is working. 

8. Inspect the course recorder to ensure that the course steered is reasonably straight under the present weather conditions. If not, re-adjust auto- pilot controis. 

9. Ensure that the lookoutman is alert.

10. Keep an eye on the weather conditions: pressure, wind direction, wind force, air temperature, swell (direction, height and period) and visibility. Inform Master of any significant change. 

11. Compile and send out appropriate Position reporting messages' such as INSPIRE, AMVER, etc. 

12. Compile and send weather reports at synoptic hours - 0000, 0600, 1200 and 1800 GMT. 

13. Switch on weather facsimile receiver (FAX) and obtain weather analysis and prognosis maps at appropriate times. 

14. Remember to advance/retard clocks as instructed by the Master. This is usually done at 2200, 0200 and 0500 hours. 

15. Comply with the instructions written in the "Master's Bridge Orders' book. 

16. Carry out verbal instructions, if any, left by Master or Chief Officer e.g., change over of FW tanks, noid ventilation, treatment of sick persons etc., if they are not mentioned in the 'Master's Bridge Orders' book. 

17. Keep a record of any unusuai or interesting events for the information of the officer coming on watch next and also the Master. For example: Change over of FW tanks, status of health of sick persons,malfunction of equipment, replacing of echo- sounder paper or course recorder roll, replace- ment of bulbs of navigation lights, passing ships of the same nationality or the same shipowner, passing naval ships, unusual meteorological phenomena observed, etc. Since these events are of current interest only, such a record need be kept only on a piece of paper on the chart table. If the event is of lasting importance, the record should be kept in the Bridge Notebook and, if necessary, entered in the Mate's Logbook after the watch is over. 

18. Keep clear of traffic and abide by ROR. 

19. in waters less than 100 metres deep, use the echo sounder every hour (every half hour if sailing close to land), ensure that the under-keel clearance is adequate and enter the results in the Depth Record Book. This book is just a notebook with the headings: Date, ship's time, position by GPS, sounding obtained, draft and depth of water. 

20. See that all persons on deck, visible from the bridge, take proper safety precautions as per "Code of safe working practices'. For example: No smoking except in designated areas, wearing of goggles while chipping, safety harness in use by all people working aloft, safety lanyards on all portable equipment above deck level, etc. 

21. The autopilot should be tested in the manual mode at least once in a watch.

22. The Magnetic Compass Off Course Alarm should be tested at least once in a watch. 

23. Entries in the Ship's Logbook should be made only after the watch is over and having been relieved by the officer of the next watch. 

24.A general round of the ship should be taken, by the officer relieved, and its results communicated to the bridge soon thereafter 

25. NEVER leave the bridge, even for a minute, unless specifically relieved by the Master or another Navigational Watchkeeping Officer. 

26. Call the Master whenever:- 

  • In doubt: this includes doubts regarding the position of own ship, safety of courses laid out for the watch, erratic or incompre- hensible movements of other ships that cause concern, etc. 

   • A close quarters situation is likely to develop. 

   • The safety of the own ship or its personnel is likely to be affected. This includes encountering restricted visibility, ice, derelicts, debris, large oil patches, sudden changes significant reduction of engine RPM, failure in atmospheric conditions,of essential navigational equipment, inability to maintain course, development of a list, doubts about the stability or watertight integrity of the ship, possibility of heavy weather damage, etc; 

   • The safety of another ship or its personnel is likely to be affected. This includes sighting of other ships that have suffered or are suffering piracy, collision. fire, grounding, man overboard, sighting of small boats in the middle of an ocean, etc. 

  • Anything unusual that warrants the Master's presence on the bridge. 


27. Never hesitate to call the master at any time. 

28. Suggested methods to call the Master: 

   • Portable VHF or by loudhailer if he is on deck. 

   • By telephone if his location in the accom- modation is known.

   • By the ship's Public Address System (PAS) if his location on board at that time is not known.

   • in the case of the loudhailer or the PAS, the communication is one way only. Hence the following type of message is suggested: 
      * Master to the bridge please. Priority (one, two or three)
      *  Priority one: Means that Master's presence on the bridge is the required as soon as possibie as there is immediate danger. 
      *  Priority two: Means that the Master's presence on the bridge is required within five or ten minutes as a dangerous situation is likely to develop.
      *  Priority three: Means that the Master should contact the bridge, at his earliest convenience, as his instruction/advice is required. 

29. After the Master comes on the bridge, the OOW may take his advice but the Oow is still in charge of the watch uniess and until the Master specifically informs him that he has taken charge. 

30. When a pilot is on board, the OOW must remain alert in all operations concerning control of the ship, fix the position on the chart frequently and satisfy himself that the actions taken are safe and understood by him. Tactful discussion with the pilot, without distracting him, would help. 


Let us now consider a few points that apply to only a few specific ships


ON GENERAL CARGO SHIPS  


1. Check smoke detector alarm system once every watch. Inspect the controi panel for visual signs of smoke every half an hour. 

2. Attend to hold ventilation - generally the exhaust blowers are ON and the ventilator cowis are turned towards leeward.


ON TANKERS 


1. Note the reading of the IG pressure gauge on the bridge and record it every hour. 

2. Attention is invited to further points, concerning tankers, mentioned in the earlier article tiled, 'Taking Over Navigational Watch at Night ',


See you in more important articles like this in the future.  Have a nice day

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