Side Boys

Side boys are a part of the quarterdeck ceremonies when an important person or Officer comes on board or leaves a ship. Large ships have side boys detailed to the quarterdeck from 0800 to sunset. When the side is piped by the BMOW, from two to eight side boys, depending on the rank of the Officer, will form a passageway at the gangway. They salute on the first note of the pipe and finish together on the last note. 

In the days of sail, it was not uncommon for the Commanding Officers of ships sailing in convoy to convene aboard the flagship for conferences. It was also not uncommon for COs to invite each other to dine aboard their vessels. Unfortunately, there was no easy way to bring visitors on and off a ship while underway. And there was no dignified may for a high ranking officer to scurry up or down a rope ladder hanging down the side of a ship. 

Often the boatswain's chair, a rope and wood sling, would be used to hoist the guest onto and off the ship. The Boatswain's Mate would control the heaving by blowing the appropriate commands with a whistle known as a Boatswain's Pipe. The number of "strong backs" needed to bring the visitor aboard depended upon the size of the "load" being hoisted. Somewhere along the line, it was noted that the more senior the visitor's rank, the more Sailors were needed to "man the side." Over time, the need to hoist visitors onto and off of Navy ships went away, but the custom of mustering the Sideboys and piping distinquished visitors aboard ship remains.

Knot

The term knot, or nautical mile, is used world-wide to denote one's speed through water. Today, we measure knots with electronic devices, but 200 years ago such devices were unknown. 

Ingenious marines devised a speed measuring device both easy to use and reliable, the "log line." From this method we get the term "Knot." The log line was a length of twine marked at 47.33-foot intervals by colored knots. At one end a log chip was fastened. It was shaped like the sector of a circle and weighted at the rounded end with lead. When thrown over the stern, it would float pointing upward and would remain relatively stationary. The log line was allowed to run free over the side for 28 seconds and then hauled on board. Knots which had passed over the side were counted. In this way, the ships speed was measured.

Crow's Nest

The raven, or crow, was an essential part of the Vikings' navigation equipment. These land-lubbing birds were carried on aboard to help the ship's navigator determine where the closest land lay when weather prevented sighting the shore. In cases of poor visibility, a crow was released and the navigator plotted a course corresponding to the bird's flight path because the crow invariably headed towards land. 

The Norsemen carried the birds in a cage secured to the top of the mast. Later on, as ships grew and the lookout stood his watch in a tub located high on the main mast, the name "crow's nest" was given to this tub. While today's Navy still uses lookouts in addition to radars, etc., the crow's nest is a thing of the past.

International code of signal and their alphabetic equivalent

Each flag represents a letter or number and can spell out a word or messsage. Each alphabetic flag can also mean a common word or phrase.

letters	phonetic alphabet	meanings
A	Alfa	Diver below, OR undergoing speed trial
B	Bravo	taking or discharging explosives
C	Charlie	Affirmative/Yes
D	Delta	Keep clear; Maneuvering with difficulty
E	Echo	Altering course to starboard
F	Foxtrot	Disabled, communicate with me
G	Golf	Need a pilot
H	Hotel	I have a pilot
I	India	Altering course to port
J	Juliette	I will send you message by semaphore; On fire with dangerous cargo, keep clear
K	Kilo	You should stop your vessel instantly. Wish to communicate
L	Lima	You should stop, I have something important to communicate
M	Mike	I have a doctor on board. Stopped and makingno way through the water
N	November	Negative/No
O	Oscar	Man overboard
P	Papa	"The Blue Peter" All aboard, vessel is about to proceed. At sea: your lights are out or burning badly
Q	Quebec	My vessel is healthy and I request free practique
R	Romeo	The way is off my ship. You may feel your way past me
S	Sierra	My engines are going full speed astern
T	Tango	Do not pass ahead of me, Keep clear, engaged in pair trawling
U	Uniform	You are coming into danger
V	Victor	I require assistance (not distress)
W	Whiskey	I require medical assistance
X	X-ray	Stop what you're doing and watch for my signals
Y	Yankee	I am carrying mails; dragging my anchor
Z	Zulu	To be used to address or call shore stations. Require tug

Flags codes

signal flags	meanings
NC	I am in distress
AC	I am abandoning my vessel
AN	I need a doctor
BR	I require a helicopter
CD	I require immediate assistance
DV	I am drifting
EF	SOS/MAYDAY has been canceled
FA	Will you give me my position?
GW	Man overboard. Please take action to pick him up
JL	You are running the risk of going aground
LO	I am not in my correct position: used by a light vessel
PD	Your navigation lights are not visible
PP	Keep well clear of me
RU	Keep clear of me; I am maneuvering with difficulty
QD	I am going ahead
QQ	I require health clearance
QT	I am going astern
QU	Anchoring is prohibited
QX	I request permission to anchor
SO	You should stop your vessel instantly
UM	The Harbor is closed to traffic
UP	Permission to enter Harbor is urgently requested. I have an emergency
YU	I am going to communicate with your station by means of the International Code of Signals
ZL	Your signal has been received but not understood.

TIDAL STREAMS

The movement of the horizontal flow of the sea is called streams. These streams when related to the rise and fall of the local tide are called tidal streams. It usually flows in and out of harbour and along the coast. The tidal stream that flow into a harbour with a rising tidal is called the “ingoing tide”. The one that flow in with a falling tide is called the “outgoing tide”. When it is off-shore, they are called according to the direction in which they flow i.e. “eastgoing” or “westgoing”. Tidal streams flow fastest where the water is deeper or the channel narrower.

Causes

Tidal streams are caused in response to the tide rising forces. It’s movements are affected by current which are caused by the differences of water temperature, barometric pressure or wing and irregularities in the seabed. It does not cause any net transfer of water with its flow.

Fathom

Fathom was originally a land measuring term derived from the Ango-Saxon word "faetm" meaning to embrace.

In those days, most measurements were based on average size of parts of the body, such as the hand (horses are still measured this way) or the foot (that's why 12 inches are so named).

A fathom is the average distance from fingertip to fingertip of the outstretched arms of a man — about six feet. Since a man stretches out his arms to embrace his sweetheart, Britain's Parliament declared that distance be called a "fathom" and it be a unit of measure. A fathom remains six feet.

The word was also used to describe taking the measure or "to fathom" something. Today, of course, when one is trying to figure something out, they are trying to "fathom" it.

Naval Coastal Battery

Naval Coastal Battery is the branch of armed forces concerned with operating anti-ship artillery or fixed gun batteries in coastal fortifications. It was also used as observation posts for soldiers who guarded the harbour.

It has been held as a general rule of thumb, that one shore-based gun equalled three naval guns of the same calibre, due to the steadiness of the coastal gun which allowed for significantly higher accuracy than their sea-mounted counterparts. Land-based guns also benefited in most cases from the protection of walls or earth mounds which gave the guns an added measure of protection.

The use of coastal artillery expanded during the Age of Discoveries, in the 16th century; when a colonial power took over an overseas territory, one of their first tasks was to build a coastal fortress, both to deter rival naval powers and to subjugate the natives. The Port Siloso at Sentosa is an excellent example of a widely used coastal fort which mounted defensive artillery, in this case muzzle-loading cannon. During the 19th century China also built hundreds of coastal fortresses in an attempt to counter Western naval threats.

Three Mile Limit

The original three-mile limit was the recognized distance from a nation's shore over which that nation had jurisdiction. This border of international waters or the "high seas" was established because, at the time this international law was established, three miles was the longest range of any nation's most powerful guns, and therefore, the limit from shore batteries at which they could enforce their laws. (International law and the 1988 Territorial Sea Proclamation established the "high seas" border at the 12-mile limit.)

 

Snake Boat Race

Man and Cheer Ship

Manning and Cheering ship as a collective mark of respect in honour of a person or of another ship is a very old custom. In the days of sail the yards and shrouds were manned as well as the decks, but now a days only decks are manned. Some example of occasions on which this mark of honour is paid are: visit of Sovereign to the Fleet, the entry into port of ships which have shared a victory, the final departure of a ship from a foreign station on her way home to pay-off.

New Year's Day - Striking 16 Bells

It is the custom for the youngest member of the ship's company to "ring out the Old Year and ring in the New" by striking 16 bells at midnight on the New Year's Eve.

Navigator's Chronometer

Next in line, and still within the orbit of the "happy ship," comes the navigator.  With the ship at sea and under way "The Pilot" seldom leaves his navigating bridge. In harbour there are his charts to correct and a number of small jobs such as checking range-finder ranges which help the gunnery officer. He also has charge of the ship's chronometers - and here again tradition steps in. 

Time was when a ship's chronometer, used for determining by calculation the ship's precise longitude at any moment, were one of the most important items of her equipment. Latitude, the other geographical dimension, could always be found from the sun at noon, or the Pole-star at night; but to find the longitude necessitated a very accurate time-keeper which was never allowed to run down and of which the error on Greenwich time was known accurately to a second from day to day.

Since in the knowledge of a ship's position at sea lies the safety of the ship the responsibility for the care of and the regular winding of the chronometers was always paramount - not only for the officers, but also for the men.

And how easy it is to forget to wind a watch or a clock - we all know that, But chronometers must not be forgotten - and, moreover, they must be wound at the same time each day. So the problem of clock forgetfulness was overcome by the simple process of requiring a Colour Sergeant, to follow the navigating officer (whose duty it is to wind the chronometers) like a shadow from eight a.m. onwards until the job has been done. Once they are wound, the "shadow" reports to the captain – "Chronometers wound" - a simple report but one which, in the old days before the advent of wireless time-signals, held in its grasp the safety of all on board. Even to-day, with wireless  pips" going almost every half-hour from one station or another, the tradition of safety is maintained and the report continues.

Semaphore

Semaphore Flags are a system for conveying information at a distance by means of visual signals with hand-held flags, rods, disks, paddles, or occasionally bare or gloved hands. Information is encoded by the position of the flags; it is read when the flag is in a fixed position. It is still used during underway replenishment at sea and is acceptable for emergency communication in daylight or, using lighted wands instead of flags, at night.

The newer flag semaphore system uses two short poles with square flags, which a signalman holds in different positions to signal letters of the alphabet and numbers. The signalman holds one pole in each hand, and extends each arm in one of eight possible directions. Except for in the rest position, the flags cannot overlap. The flags are coloured differently based on whether the signals are sent by sea or by land. At sea, the flags are coloured red and yellow (the Oscar flag), while on land, they are white and blue (the Papa flag). 

Displacement of a ship

A ship's displacement is its mass at any given time, generally expressed in metric tons or long tons. The term is often used to mean the ship's mass when it is loaded to its maximum capacity. A number of synonymous terms exist for this maximum mass, such as loaded displacement, full load displacement and designated displacement. Displacement is a measurement of mass, and should not be confused with similarly named measurements of volume or capacity such as net tonnage, gross tonnage, or deadweight tonnage.

The word displacement refers to the mass of the water that the ship displaces while floating. Another way of thinking about displacement is the amount of water that would spill out of a completely filled container, were the ship to be placed into it. A floating ship always displaces an amount of water of the same mass as the ship.

The density (mass per unit of volume) of water can vary. For example, the average density of seawater at the surface of the ocean is 1025 kg/m³ (10.25 lb/gallon, 8.55 lb/US gallon), fresh water on the other hand has a density of about 1000 kg/m³ (10.00 lb/ga, 8.35 lb/US gallon). Consider a 100-ton ship passing from a saltwater sea into a freshwater river. It always displaces exactly 100 tons of water, but it has to displace a greater volume of fresh water to amount to 100 tons. Therefore it would sit slightly lower in the water in the freshwater river than it would in the saltwater sea.

It can be useful to know a ship's displacement when it is unloaded or partially loaded. Terms for these measurements include light displacement, standard displacement, and normal displacement. These terms are defined fully below.

Mediterranean Mooring

In some harbours where there is sufficient room to berth many ships alongside, ships may be obliged to berth at right-angles to a jetty, with their sterns secured to it by berthing lines and their anchors(s) laid out ahead.

This type of mooring can only be employed where there is a negligible range of tide, and is commonly used in Mediterranean ports; for this reason it is often called the Mediterranean (or Med) moor. 

The major considerations are to veer sufficient cable so that the ship can swing clear of other ships at the berth when leaving, to lay the anchors sufficiently far apart to make the ship more secure in wind, and to ensure the anchors do not foul those of other ships. 

In a shallow harbour it is recommended that a frigate veers about 4 shackles of cable on each anchor, and that cables are spanned with and included angle of about 50 degrees, so as to make the ship more secure in a wind. It is obvious, however, that to berth will not be safe if a gale blows from abeam.

If such weather is forecast it is advisable to put to sea or seek a sheltered anchor berth. Ships fitter with a single anchor can, in theory, carry out a Med moor; however, the single anchor will hold the bows steady only in benign weather conditions.

Hypothermia

Hypothermia is a lowered body temperature less than 95 degrees F. Cold water near-drowning is considered a submersion accident often leading to unconsciousness or coma in water temperatures of 70 degrees F or less. A long submersion time is considered 4 to 6 minutes or greater.


Hypothermia may be mild, moderate, or severe. The presentation may range from shivering and piloerection ("goosebumps"), to profound confusion, irreversible coma and death. Significant hypothermia begins at temperatures of 95 degrees F and below. The lowering of the body temperature occurs as the body is robbed of heat by the surroundings.


Water conducts body heat away up to 26 times faster than air of the same temperature. Normal body functions slow down with decreasing heart rate, decreasing respiratory and metabolic rate. Thinking is impaired and speech becomes confused. Reflexes are slowed and muscles become stiff and unusable. Then dangerous life-threatening heart rhythms develop which are hard to reverse.
Hypothermia is the opposite of hyperthermia, the condition that causes heat exhaustion and heat stroke.


Hypothermia describes a state in which the body's mechanism for temperature regulation is overwhelmed in the face of a cold stressor. All survivors should know that hypothermia is a potential killer.