Ship Structural Basics

Ship Structural Basics

• Length Overall (LOA) represents the maximum length of the ship.
• The Forecastle is the forward part of the ship's structure.
• The Bridge is the area from which the ship is controlled.
• The Stern or Poop is the aft or rear part of the ship.
• Breadth is the width of the ship.
• Registered Length is the length registered with authorities.
• L.P.P. (Length between Perpendiculars) is the length between the forward and aft perpendiculars.
• Abeam refers to a direction at right angles to the ship's centerline.
• Bow is the forward part, while Stern is the rear part of the ship; Starboard is the right side, and Port is the left side when facing forward.
• Length Over All (LOA) is the total length; Registered Length is used for legal purposes and L.P.P. is for design calculations.
• Draft is depth of vessel
• Freeboard is the distance from the waterline to the upper deck, indicating reserve buoyancy.
• Height indicates the vertical extent of the ship.
• Under-Keel Clearance is the distance between the keel and the sea bottom.

Signal Flags and Their Meanings

• Alfa: "I have a diver down; keep well clear at slow speed." Accompanied by three numerals to indicate azimuth or bearing.
• Bravo: "I am taking in, or discharging, or carrying dangerous goods."
• Charlie: "Affirmative." Used with three numerals to indicate course in degrees magnetic.
• Delta: "Keep clear of me; I am maneuvering with difficulty." May be accompanied by two, four, or six numerals to indicate the date.
• Echo: "I am altering my course to starboard."
• Foxtrot: "I am disabled; communicate with me."
• Golf: "I require a pilot." For fishing vessels operating in close proximity, it means "I am hauling nets." Can be used with four or five numerals for longitude.
• Hotel: "I have a pilot on board."
• India: "I am altering my course to port."
• Juliet: "I am on fire and have dangerous cargo on board: keep well clear of me, or I am leaking dangerous cargo."
• Kilo: "I wish to communicate with you." Accompanied by one numeral to indicate the method of communication.
• Lima: "In harbor: The ship is under Quarantine." "At sea: You should stop your vessel instantly." With four numerals, it indicates latitude.
• Mike: "My vessel is stopped and making no way through the water."
• November: "Negative."
• Oscar: "Man overboard."
• Papa: "In harbor: All persons should report on board as the vessel is about to proceed to sea." At sea, used by fishing vessels to mean "My nets have come fast upon an obstruction".
• Quebec: "My vessel is 'healthy' and I request free pratique."
• Romeo: "The way is off my ship." With one or more numerals, it indicates distance in nautical miles.
• Sierra: "I am operating astern propulsion." Used with one or more numerals to indicate speed in knots.
• Tango: "Keep clear of me; I am engaged in pair trawling." Accompanied by four numerals to indicate local time.
• Uniform: "You are running into danger."
• Victor: "I require assistance." With one or more numerals, indicates speed in kilometers per hour.
• Whiskey: "I require medical assistance."
• X-ray: "Stop carrying out your intentions and watch for my signals."
• Yankee: "I am dragging my anchor."
• Zulu: "I require a tug." For fishing vessels operating in close proximity, it means "I am shooting nets". Used with one or more numerals to indicate time (UTC).
• First Sub: Repeats the first character in the sequence.
• Second Sub: Repeats the second character in the sequence.
• Third Sub: Repeats the third character in the sequence.
• Fourth Sub: Repeats the fourth character in the sequence.

SMCP General: Spelling and Procedures

• Letters are spelled using specific code words like Alfa, Bravo, Charlie, etc. for clarity.
• Numbers are pronounced using code words; Zero is "ZEERO", One is "WUN", Two is "TOO", Three is "TREE", etc.
• The Decimal point is indicated by "Decimal" and Full Stop by "Stop".
• DTG (Date Time Group) uses a 24-hour clock system with four figures of time (hhmm) and UTC is indicated by hhmm+Z.
• A six-figure group is used for the date, using ddhhmm.
• Geographical positions are indicated using latitude and longitude, specifying degrees and minutes, N/S, E/W.
• Bearings are indicated using 360 degrees notation from true north, except in the case of relative bearings.
• Courses are expressed in 360 degrees notation (TO or FROM).
• Distance is expressed in nautical miles or cables (0.1 NM).
• Speed is expressed in knots.
• When the answer is affirmative: respond "Yes, ...".
• When the answer is negative: respond "No, ...".
• When the information isn't immediately available: respond "Stand by ...".
• When unable to obtain the information requested: respond "No information.".
• When an instruction is given, respond in the affirmative with "I will/can ..." or in the negative with "I will not/cannot ...".
• MAYDAY is used to announce a distress message.
• PAN - PAN is used to announce an urgency message.
• SECURITE is used to announce a safety message.
• Readability of reception is indicated by "How do you read (me)?", answer uses signal strength.
• To remain on a VHF Channel/frequency: "Stand by on VHF Channel [number] / frequency... ."
• When accepted to remain on the VHF Channel/frequency: "Standing by on VHF Channel [number] / frequency... ."
• When it's advisable to change to another VHF Channel / frequency: "Advise (you) change to VHF Channel [number] / frequency ... ."
• When the changing of a VHF Channel / frequency is accepted: "Changing to VHF Channel [number] / frequency ... !"
• The word May is ambiguous, use "QUESTION, Do I have permission to enter the fairway?"
• The word Might is ambiguous, use “INTENTION. I will drop the anchor."
• The word Should is ambiguous, use "ADVICE. Anchor east of buoy D 5."
• The word Can is ambiguous, use "“QUESTION. Do I have permission to use the shallow draft fairway?"