(Pls read this in conjunction with pervious topic of continuous position monitoring.)
One must always pay attention to below:-
1. Make a detailed passage plan with distances/clearances and when any of the reference/limits are getting breached, what is your maximum tolerance, recheck your clearances with radar. And what are your options.
2. What is the wind speed and direction
If beam wind if preventing from building adequate ROT, immediately put wheel hard over and use Short burst of higher RPM instead of losing precious time and vessel moving too close to edge/danger
Turning away from wind may be very difficult. Has any VLCC(in Ballast) or Container master experienced that vessel is not turning to stbd with wind More than 30 knots from port bow just after picking up anchor. This is more of an issue for VLCC in ballast due to very high windage area and comparatively less engine power. So plan in advance, if there is possibility to approach differently by turning into the wind.
Normally any time wind more than 15 knots, you must pay lots of attention to anticipated wind effects while planning and executing maneuver.
3. Tide
Tide is single most important factor in shiphandling, berthing and unberthing. During unberthing time not giving due consideration to tide may create difficult situation very rapidly, hence it is utmost important to pay due consideration to tide before unberthing. Normally during inward passage/berthing since we had already been tackling tide during approach, we are aware of it, but during unberthing due to complacency or hurry we forget to check tide.
Always be aware of tidal flow. Where vessel will drift. Specially be cautious in location with sudden change of tide like entering breakwater or some shoal/island creating change in flow of water. I suggest Masters try to build up rapport with pilots, try to pick up these local peculiarities from him.
When reducing speed, keep in mind that your drift will increase, so you must increase your set angle as you reduce speed. If by you are asked to wait or hold your position waiting for pilot, head you bow into the current before completely stopping the vessel.
Develop habit of observing visually the flow of tide by checking buoys, flow of water under the jetty piles, flow of tugs wake etc.
For more info read https://www.shiphandlingpro.com/effect-of-current-tidal-stream
4. What tugs are made fast
I suggest all Master should make a small pocket card. Draw your vessel, draw final berthing clearances fwd and aft, mark at what bollard number your bridge will be positions at berth, wind speed direction, current direction and draw position of tugs, names and bollard pull, Channel of communication so that they are ready to communicate with tugs in case pilot is incapacitated.
Image: Sample bridge wing card
Master should keep this card in front of him even when he is on bridge wing. (Don’t leave it behind on chart table or be ignorant about it), And I suggest you draw by hand instead of using readymade templates as when you draw, you tend to be more involved and you will have better situational awareness
Typical tugs order for a 50 ton tug with approximate forces:
Line tight/touch push - 10 ton
Slow pull/push - 20 ton
Half pull/push - 30 ton
Full pull/push - 40 ton
Max Pull/push - 50 ton (only for short duration in extreme emergencies as it creates huge stress on tugs engine)
Studying some more about tugs will help in long run.
5. What is your speed and engine status/ keeping reserve power for short kicks.
If you are approaching sharp bends, your speed should be less than your engine speed…?
Say you are approaching a bend at speed 8 knots and also your are now planning to reduce speed, so now you kept engine at dead slow ahead, your dead slow ahead speed is only 4 knots. Now the water thrust force created by propeller is slower than the water flow speed of 8 knots, hence thrust of water hitting propeller is not very strong. If your vessel is not building adequate ROT due to this, you may be forced to go half ahead or full ahead on engine to generate enough thrust on rudder. Hence it is advisable to reduce speed to optimum before reaching the sharp bend so that you will have adequate thrust force on rudder, if required you can also use short burst of higher engine. Using higher engine for short duration is advisable with wheel hard over. E.g. it’s better to use burst of half ahead and quickly generate ROT instead of using slow ahead for longer duration as latter will cause vessel to pick up speed.
6. If pilot is incapacitated, even 5 meter from the berth, Master should never try to berth the vessel, it is always advisable to use tugs to pull out the vessel and abort berthing. Because If Master tries to berth the vessel and some incident happens, there may be severe financial liabilities.
7. A Pilot is always thinking of contingencies. As a Master we must also think about what can go wrong at each stage of passage, what are contingencies. Never over commit, as Navigation related mistakes can turn out to be very costly.
8. And in last, avoid distractions while navigating, avoid using mobile, frequently going and checking computer etc.
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