Watchkeeping, Navigation Bridge

Q. What is the responsibility of the officer in charge of the navigational watch regarding not leaving the bridge?
The watchkeeper must in no circumstance leave the bridge until properly relieved. The navigation bridge at times is manned additionally by a helmsman and a lookout man. In certain situations the lookout man may not be there. The helmsman if absent, may be employed for some maintenance in close vicinity. The watchkeeper, however cannot leave the bridge. If he must go to the chartroom, it must be for a period as small as possible and after assuring that it is safe to do so.

Q. If the Master comes on bridge, who is responsible for the safe navigation?
The duty officer continues to be responsible for the safe navigation of the ship, despite the presence of the Master on the bridge, until the Master specifically informs the duty officer that the Master has assumed the responsibility and this is mutually understood. The duty officer, however must notify the Master when in any doubt as to what action to take. Even when Master has taken over stating this officially, the officer on watch must be vigilant about the situation and discuss the situation, targets, etc. with the Master.

Q. How will you know that the charted course is actually followed?
During the watch, the course steered, position and speed shall be checked at sufficiently frequent intervals, using any available navigational aids necessary, to ensure that the ship follows the planned course. A continuous monitoring can be done using parallel indexing technique.

Q. What precaution will you take prior altering course?
The new course is reconfirmed using the parallel ruler. The second officer might have made mistakes in writing the course. The wheel-over line can be ascertained and plotted, particularly when the second course is through restricted passage or narrow channel, etc. The duty officer must follow a practice so that there is a positive reminder in respect of the alteration point. Usually, a conspicuous light may be found abeam at the time of alteration. An appropriate rate of turn and application of the wheel while at wheel over line will ensure that the vessel is on the final course line.

Q. Why is it better to have a light abeam at alteration point?
It is for the following reasons:

  1. When a light is abeam, the bearing is course +/- 900, hence bearing need not be taken from repeater.
  2. The light coming forward of beam is a reminder that the alteration point is being approached.
  3. Usually, with the light being abeam the distance is closest, hence the error in position would be least.

Q What is the relation between radius of turn and the rate of turn per minute?
Rate of turn per minute to be maintained should be speed the ship is doing divided by the radius of turn. The helmsman must be trained to steer maintaining a given rate of turn per minute.

Q.  How do you ensure that the radius of turn is constant?
The speed of the ship reduces as she turns. To maintain a constant radius, the rate of turn must be reduced in the same proportion as the speed. Thus, if ship,s speed is 12 kn and radius of turn is 2M, the rate of turn should be 6. The rate of turn should be reduced to 5.5 if the speed reduces to 11kn.

Q. What must the duty officer know about the navigational equipment?
The officer in charge of the navigational watch must have full knowledge of the location and operation of all safety and navigational equipment on board the ship and shall be aware and take account of the limitations of such equipment. The most effective use of all navigational equipment must be made. OOW must be thoroughly familiar with the use of all electronic navigational aids carried, including their capabilities and limitations. The echo-sounder and radar provide warning in vertical and horizontal directions respectively and must be always used without hesitation, to rule out any doubt.

Q. In a sea watch, can the watchkeeper be given the task of taking inventory of publications?
The officer in charge of the navigational watch must not be assigned any duty. Any work that would interfere with the safe navigation of the ship must not be undertaken by the watchkeeper. It is the human nature that any kind of diversion can drive the mind off the subject and the period for which you are diverted is likely to increase unknowingly.

Q. What is the responsibility of an OOD while using the radar?
The most important thing to ensure when using the radar is to be aware about the range scale in use. The clutter settings and tuning should be checked frequently. The International Regulations for Preventing Collisions at Sea, in force must be duly complied with. The officer in charge of the navigational watch must use the radar whenever restricted visibility is encountered or expected, and at all times in congested waters having due regard to its limitations. The second radar must be checked for confirmation, comparison, etc. The plotting or systematic observation must be done when needed.

Q. Can the OOD alter course or use the engines at his disposal?
In cases of need, the officer in charge of the navigational watch must not hesitate to use the helm, engines and sound signaling apparatus. However, timely notice of intended availability of maneuvering engine speed shall be given where possible. The use of UMS engine controls provided on the bridge should be possible.

Q. Why the watchkeeping officer on navigation bridge must have the knowledge of maneuvering characteristics?
Officer of the navigational watch must know the handling characteristics of his ship, including her stopping distances. The amount of alteration and its effectiveness in an ROR situation or a situation where a danger has to be averted can be duly assessed only if the OOD has a good idea of maneuvering characteristics. He must also appreciate that other ships may have different handling characteristics or may not be taking appropriate actions.

Q. What facts must be recorded by the duty officer?
A proper record shall be kept during the watch of the movements and activities relating to the navigation of the ship. Thus, the passing of a navigational object, an engine movement, any important reporting, boarding / disembarking of pilot, etc are recorded in addition to the other events which are entered in the normal watch.

Q. What is the provision in respect of lookout?
At all times the officer in charge of the navigational watch must ensure that a proper look-out as stated in the colregs is maintained. This will involve the following:

  1. maintaining a continuous state of vigilance by sight and hearing as well as by all other available means, with regard to any significant change in the operating environment;
  2. fully appraising the situation and the risk of collision, stranding and other dangers to navigation; and
  3. detecting ships or aircraft in distress, shipwrecked persons, wrecks, debris and other hazards to safe navigation. The look-out must be able to give full attention to the keeping of a proper look-out and no other duties shall be undertaken or assigned which could interfere with that task.

Q. Is it appropriate that the second officer corrects the charts in the chart room?
In a ship with a separate chart room the officer in charge of the navigational watch may visit the chart room, when essential, for a short period for the necessary performance of navigational duties, but shall first ensure that it is safe to do so and that proper look-out is maintained. The chart correction, particularly in the chart room must not be done. Many masters object to any correction of charts or publications during the watchkeeping.

Q. When should you test shipboard navigational equipment?
Operational tests of shipboard navigational equipment shall be carried out at sea as frequently as practicable and as circumstances permit. They must be checked prior anticipated use. Whenever appropriate, these tests shall be recorded. Such tests shall also be carried out prior to port arrival and departure at suitable interval before the arrival or departure.

(You may also visit my youtube videos

Leave a Reply

%d bloggers like this: