USCG Master 100 flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Overtaking vessel

Rule 13: any vessel overtaking another must keep clear of the vessel being overtaken until finally past and clear; if in doubt, treat the situation as overtaking.

Head-on meeting

Rule 14: two power-driven vessels meeting head-on or nearly so each alter course to starboard and pass port to port.

Crossing situation

Rule 15: when two power-driven vessels cross, the one with the other on her starboard side is the give-way vessel and must keep clear.

Stand-on vessel duty

Rule 17: the stand-on vessel keeps her course and speed but may sound a warning, and must act if collision cannot be avoided by the give-way vessel alone.

Restricted visibility

Rule 19: in fog, heavy rain, or similar conditions, proceed at a safe speed for the circumstances, sound the proper signals, and no vessel has the right of way.

Danger signal

Five or more short and rapid blasts on the whistle means doubt about the other vessel's intentions or that a risk of collision exists.

Sidelight arc

Each sidelight shows over 112.5 degrees, from dead ahead to 22.5 degrees abaft the beam; red is on the port side and green is on the starboard side.

Masthead light arc

A masthead light shows over 225 degrees, from dead ahead to 22.5 degrees abaft each beam, and is white; required ranges depend on vessel length.

Speed-time-distance formula

Distance equals speed in knots multiplied by time in hours; when time is given in minutes, divide speed times minutes by 60.

TVMDC

Compass conversion sequence: from True apply easterly or westerly variation to get Magnetic, then apply deviation the same way to get Compass.

Minute of latitude

One minute of latitude equals one nautical mile, about 6,076 feet; one minute of longitude equals one nautical mile times the cosine of the latitude.

IALA Region B

In the United States, red buoys with even numbers mark the starboard side when returning from sea, while green buoys with odd numbers mark the port side.

Dip of the horizon

The dip in nautical miles is about 1.17 times the square root of the height of eye in feet; it is subtracted from the observed sextant altitude.

Rule of twelfths

Estimates tidal height change: over the six hours of a tide, the fractions of total rise per hour are 1/12, 2/12, 3/12, 3/12, 2/12, and 1/12.

Set and drift

Set is the direction toward which a current flows and drift is its speed in knots; both are plotted as a vector from the dead reckoning position.

Preferred channel buoy

A red and green horizontally banded buoy marks a channel junction; the color of the top band shows the side on which the preferred channel lies.

Bowline

A knot forming a fixed loop at the end of a line that will not slip or jam, used for passing a line around a post or over a bitt.

Clove hitch

A hitch of two half hitches around an object, used to secure a line to a piling or rail, but it can slip under an intermittent load.

Safe working load

The maximum load that line, wire, or chain may safely carry, calculated as the breaking strength divided by a safety factor of about five or six.

Anchoring scope

The ratio of anchor rode length to water depth; use about 5 to 7 times the depth, and more in heavy weather to keep the shank horizontal.

Right-hand propeller

A propeller that turns clockwise when viewed from astern while going ahead; when backing, the vessel's stern tends to walk to port.

Free surface effect

Liquid that can shift in a partially filled tank moves to the low side, raising the center of gravity and reducing metacentric height and stability.

Righting moment

Displacement multiplied by the righting lever GZ; it is the moment that returns a heeled vessel upright and must exceed the heeling moments.

Class B fire

A fire in flammable liquids such as gasoline, diesel, or oil; extinguish with foam, carbon dioxide, or dry chemical, never with a water stream.

MAYDAY

The radiotelephone distress signal for grave and imminent danger requiring immediate assistance, transmitted on VHF channel 16 or 2182 kHz.

PAN-PAN

The urgency signal for a situation concerning the safety of a vessel or person that does not yet require immediate assistance; spoken three times.

PASS

Fire extinguisher technique: Pull the pin, Aim at the base of the flames, Squeeze the handle, and Sweep the nozzle side to side.

EPIRB

An emergency position indicating radio beacon on 406 MHz; float-free or manual, registered to the vessel, it alerts rescue services with the vessel's identity.

Man overboard first actions

Shout man overboard, throw a life ring, put the rudder hard over toward the side the person fell, and post a lookout to keep the person in sight.

Hypothermia

Body core temperature falls below normal after cold water immersion; the H.E.L.P. posture conserves heat and avoids movement that circulates cold blood.

Commercial BAC limit

A person operating a commercial vessel with a blood alcohol content of 0.04 percent or more is subject to enforcement action by the Coast Guard.

Abandon ship procedure

Send a MAYDAY with position, don immersion suits, launch the liferaft, take the EPIRB and water, take a head count, and the master leaves last.