The squat effect is the hydrodynamic phenomenon by which a vessel moving quickly through shallow water creates an area of lowered pressure that causes the ship to be closer to the seabed than would otherwise be expected. This phenomenon is caused when water that should normally flow under the hull encounters resistance due to the close proximity of the hull to the seabed. This causes the water to move faster, creating a low-pressure area with lowered water level surface
as per rule number 13 part (B),
a vessel shall be deemed to be overtaking when coming up with other vessel frm a direction more than 22.5 degree abaft her beam, that is , in such a position with the ref. to the vessel she is overtaking , that at night she would be able to see only the stern light of that vessel bt nither of her side lights
when the vessel coming from 22.5degree abaft the beam of own vessel then it is said to vessel overtaking
A vessel is said to be overtaking when coming up from the direction of 22.5 deg abaft of the beam in such position with the ref. of overtaking vessel she will be able to sea at night time only the stern light neither of her side lights.
international convention for prevention of pollution from ship
MARPOL is an international regulation made for prevention of marine pollution
In 1973 IMO has organised a conference in which they have passed two protocols in P-1 they made a report from the past accidents caused by the harmfull substances and in P-11 they introduce the aritarbution.this conference conducted from 19th oct to 2nd nov 1973. And in 1978 IMO again called a conference and passed five different annex from annex-1 to annex-5 and in 1997 they introduce the annex-6.
these all annex includes the regulation for the prevention of marine pollution or we can say MARPOL 1973/78.
total mass of cargo,fuel,f/w,etc that a ship can carry at the time she is floating in SW with her summer loadline at the water surface.
When a ship is delivered from the yard (with machinery, appurtenances, fixtures) its weight without stores, fuel, crew, etc is called "Light ship". Anything weight which is not a part of Light Ship is called deadweight. Eg Crew, fuel, stores, ballast, cargo, lubes etc.
Deadweight tonnage (often
abbreviated as DWT for
deadweight tonnes) is the
displacement at any loaded
condition minus the lightship
weight. It includes the crew,
passengers, cargo, fuel, water,
and stores. Like Displacement, it
is often expressed in long tons or
in metric tons.
WIG craft move at high speed. to distinguish from distance
Air cushioned vessel r susceptible to wind effect.
brendon n kamlesh
1) Inform Master.
2) Inform E/R.Get engines ready for manoeuvering.
3)obsrve visually and make a note of all the traffic in sight,
4)switch on ARPA and commence plottng.
5)Switch on navigational lights.
6) change over to hand sterering,
7) switch on the other stering motor,
8) post double lookouts, one on the bridge wing, other on forecastle.
9)try out pneumatic wistle and electric klaxon and the manual foghorn, by giving a very short blast on each, try out automatic fog signal unit,
10) stop all noises on decks so that the fog signals of other vessels would not get drowned in the noise ,,
11) keep open the outer doors of the wheel house so that the fog signals of other ships may be heared, even if they are very faint,
12) commence sounding fog signal before entering into the fog.
13) reduce to safe speed before entering fog.
14)restrict hold ventilation.
15) record all the happnings in bridge record book.
inform master n engine room
post look outs
switch on n operate radar
switch on nav lights
activate sound signals
proceed at safe speed
brendon n kamlesh
inform to master, stop all noisy work, switch on the navigational lights, one pro longed blast in interval not more than 2 min
inform to master
inform to engine room keep the engine raedy to manouvere and in safe speed
start sounding the signal as per ror
stop all noisy work like chipping
switch on all navigation lights
keep the bridge wing door open
continuos observation of radar and arpa mUST
keep plotting the position by all available means
if it idicates the presence of any other vessel,acess the suitation and take the action immidiately in ample time
Garboard strake is the first horizontal wooden strip laid next to the keel of a wooden ship
sheer strake is the longitudinal upward curwature of the deck, gunwale and lines of vsl as when viewed from the side