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International Bareboat Skipper > Buoyage, Charts & Navigation > Flashcards

Buoyage, Charts & Navigation Flashcards

1
Q

What is IALA?

A

International Association of Lighthouse Authorities

All navaids within IALA are distinguished by:

Shape
Light
Colour
Topmark
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2
Q

IALA Region A

A
  • Europe and most of the world
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3
Q

IALA Region B

A
  • North and South america
  • Caribbean
  • Japan, Korea and Philippines
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4
Q

Describe the basic rules for IALA Zone A

A
  • Port marks are red, can shaped and may have a red flashing light of any rhythm
  • Starboard marks are green, cone shaped and may have a green flashing light of any rhythm

“Is there any red port left”

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5
Q

Decribe the basic rules for IALA zone B

A
  • Port marks are green, can shaped and may have a green flashing light of any rhythm.
  • Starboard marks are red, cone shaped and may have a red flashing light of any rhythm.

“Red right returning”

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6
Q

What is the shape of port marks in the IALA system?

A
  • Square/can shape or have a can shape topmark
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7
Q

What is the shape of starboard marks in the IALA system?

A
  • Conical or have a conical shaped top mark
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8
Q

Describe this Buoy. What system is it associated with?

A
  • Square can shaped
  • Port hand mark
  • Red
  • IALA system A
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9
Q

Describe this Buoy. What system is it associated with?

A
  • Conical shaped
  • Starboard hand mark
  • Green
  • IALA system A
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10
Q

Describe this Buoy. What system is it associated with?

A
  • Can shaped
  • Port hand mark
  • Green
  • IALA system B
  • (F) 1s or 4s
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11
Q

Describe this Buoy. What system is it associated with?

A
  • Conical in shape
  • Starboard hand mark
  • Red
  • IALA system B
  • (Fl) 1s or 4s
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12
Q

Isolated Danger Buoy

A
  • Indicates a point of potential hazard
  • Red and Black in colour
  • Have two round balls at the top
  • White light Fl(2)5s or 10s
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13
Q

Describe this Buoy.

A
  • Red and Black
  • Two round balls at top
  • Isolated Danger Buoy
  • Fl(2)5s or 10s
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14
Q

Safe Water Mark

A
  • Used to indicated end/start of a channel, open, deep and safe water lies ahead.
  • Red and white vertical stripes
  • Also known as a fairway Buoy
  • White light and will flash Morese code A, occulting, Isophase or long flash every 10 seconds
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15
Q

Special Mark

A
  • Indicate the boundary of an obstruction, administrative area such as a speed limit, water skiing or mooring area
  • Yellow in colour
  • Yellow light one quick flash every 5 seconds
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16
Q

Wreck Buoy

A
  • Used to temporarily indicate a wreck until the wreck is cleard or permanent marks are set up.
  • Alternating blue and yellow light
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17
Q

Describe this Buoy

A
  • North Cardinal Buoy
  • Black over yellow
  • Both triangles pointing up
  • White light with continuous flash
  • Vessels should pass hazard to the North
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18
Q

Describe this Buoy

A
  • East Cardinal Buoy
  • Black/Yellow/Black
  • Triangles pointed away
  • White light Flashing in group of 3
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19
Q

Describe this Buoy

A
  • South Cardinal Buoy
  • Yellow over Black
  • Triangles pointed down
  • White light flash in group of 6 followed by 1 long flash
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20
Q

Describe this Buoy

A
  • West Cardinal Buoy
  • Yellow/Black/Yellow
  • Triangles point in
  • White light flash in group of 9
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21
Q

(Fl)4s

A
  • A light with 1 flash every 4 seconds
  • 15 flashes per minute
  • 0.5 sec flash; 3.5 sec. eclipse
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22
Q

Mo(A)6s

A
  • Morse Code A
  • A white light in which a 0.3 second flash is followed by a 0.6 second eclipse then a 1 second long flash repeated at a rate of 10 times per minute
  • Fairway Buoy
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23
Q

(Q)1s

A
  • A white light in which indentical flashes are repeated at a rate of 60 flashes per minute (1 flash every second)
  • North Cardinal Buoy
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24
Q

Q(3)10s

A
  • A white light in which a group of 3 flashes is regularly repeated 6 times per minute every 10 seconds.
  • East Cardinal Buoy
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25
Q

(Q(6)+LFl)15s

A
  • A white light in which a group of 6 quick flashes is followed by a single long flash. Repeated 4 times per minute or every 15 seconds
  • South Cardinal Buoy
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26
Q

Q(9)15s

A
  • A white light in which a group of 9 flashes is repeated 4 times per minute or every 15 seconds.
  • West Cardinal Buoy
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27
Q

FI(2)5s

A
  • A white light in which a group of 2 flashes is regularly repeated 12 times per minute or every 5 seconds.
  • Isolated Danger Buoy
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28
Q

Bifurcation Buoys

A

A bifurcation buoy is used to mark the point where a channel divides into different branches. They can be passed on either port or starboard side when travelling upstream but the prefered channel is the one indicated by the color of the top band.

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29
Q

Describe this Buoy

A
  • Port Bifurcation Buoy
  • Green Red Green
  • Green light, Fl(2+1)6s
  • The preferred channel is to the right (starboard)
  • You should keep the buoys on your port (left) side
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30
Q

Describe this Buoy

A
  • Starboard Bifurcation Buoy
  • The preferred channel is to the left (port)
  • These buoys are kept on your starboard (right) side
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31
Q

Describe this Buoy

A
  • Fairway Buoy
  • This buoy marks safe water at landfalls, channel entrances or channel centres
  • Should be kept on the port (left) side when going in either direction
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32
Q

Describe this Buoy

A
  • Anchorage Buoy
  • Yellow with anchor symbol
  • Flashing yellow light
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33
Q

Cautionary Buoys

A
  • Yellow buoys
  • Mark danger areas such as areas where there is no safe channel, underwater hazards
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34
Q

Describe this Buoy

A
  • Mooring Buoys
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35
Q

Information Buoy

A
  • Orange symbol on white pillars, cans or spars
  • Squares provide information such as places to find food, supplies and repairs
  • They also give direction, distances and other non-regulatory information
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36
Q

Hazard Buoy

A
  • Orange symbols on white pillars, cans or spars
  • Diamonds warn of hazards such as rocks, shoals, or turbulent waters.
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37
Q

Control Buoy

A
  • Orange symbol on white pillar
  • Circles indicate a restricted boating area such as no wake, idle speed, speed limit or wash restrictions
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38
Q

Keep-Out Buoys

A
  • Orange symbols on white pillars, cans or spars
  • Crossed diamonds indicate areas where pleasure craft are prohibited such as dams and spillways
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39
Q

Describe this day beacon

A
  • Starboard hand day beacon
  • Red triangle in the centre of a white background and red border
  • Keep on your starboard side when travelling upstream
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40
Q

Describe this day beacon

A
  • Port Hand Day Beacon
  • They have a black or green square in the centre of a white bacground and a green border
  • Keep them on your port side when travelling upstream
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41
Q

Describe this day beacon

A
  • Port Bifurcation Day Beacon
  • Junction (preferred channel to right)
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42
Q

Describe this day beacon

A
  • Starboard Bifurcation
  • Junction (Preferred channel to left)
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43
Q

Identify this chart symbol

A
  • North Cardinal Buoy
  • Black over yellow
  • Two upward triangles
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44
Q

Identify this chart symbol

A
  • East Cardinal Buoy
  • Black Yello Black
  • Traingles in opposite direction
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45
Q

Identify this chart symbol

A
  • South Cardinal Buoy
  • Yellow over black
  • Triangles facing downward
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46
Q

Identify this chart symbol

A
  • West Cardinal Buoy
  • Yellow/Black/Yellow
  • Triangles facing inward
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47
Q

Identify this chart symbol

A
  • Isolated Danger Buoy
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48
Q

Identify this chart symbol

A
  • Isolated Danger Buoy with white light
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49
Q

Identify this chart symbol

A
  • Safe Water Mark
  • Red and white vertical stripes
  • Safe water such as midchannel and landfall marks
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50
Q

Identify this chart symbol

A
  • Safe Water Mark with white light
  • Red and white vertical stripes
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51
Q

Identify these general chart symbols

A
  • Special Marks
  • Not primarily used to assist navigation but to indicate special features
  • Examples include, cautionary buoys, information and control buoys, hazard buoys etc…
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52
Q

Identify this chart symbol

A
  • Buoy or beacon symbol out of position
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53
Q

Identify this chart symbol

A
  • Starboard Hand Buoy
  • Red
  • Conical shape
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54
Q

Identify this chart symbol

A
  • Starboard Hand Buoy
  • Red
  • Red flashing light
  • Conical in shape
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55
Q

Identify this chart symbol

A
  • Port Hand Buoy
  • Green
  • Can shaped
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56
Q

Identify this chart symbol

A
  • Port Hand Buoy
  • Green
  • Green flashing light
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57
Q

Identify the chart symbol

A
  • Safe Water Buoy, Fairway Buoy
  • Red and White vertical stripe
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58
Q

Identify this chart symbol

A
  • Starboard Bifurcation Buoy
  • Red Green Red
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59
Q

Identify this chart symbol

A
  • Starboard Bifurcation Buoy
  • Red Green Red
  • Red flashing light
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60
Q

Identify this chart symbol

A
  • Port Bifurcation Buoy
  • Green Red Green
61
Q

Identify this chart symbol

A
  • Cautionary Buoy
  • Anchorage Buoy
  • Yellow
62
Q

Identify this chart symbol

A
  • Keepout Buoy
  • Control Buoy
  • Information Buoy
63
Q

Identify this chart symbol

A
  • Diving Buoy
64
Q

Identify this chart symbol

A
  • Fixed point
65
Q

Identify this chart symbol

A
  • Flood tidal stream with rate
66
Q

Identify this chart symbol

A
  • Ebb tidal stream with rate
67
Q

Identify this chart symbol

A
  • Ebb tidal stream with rate
68
Q

Identify this chart symbol

A
  • Position of tabulated tidal stream data with designation
69
Q

Identify this chart symbol

A
  • Sounding in true position
70
Q

Identify the following chart symbol

S

A

Sand Seabed

71
Q

Identify the following chart symbol

R

A

Rock Seabed

72
Q

Identify the following chart symbol

Cy

A

Clay Seabed

73
Q

Identify the following chart symbol

A

Kelp, Weed Seabed

74
Q

Identify the following chart symbol

A

Weed(including kelp) Seabed

75
Q

Identify the following chart symbol

Si

76
Q

Identift this chart symbol

G

77
Q

Identify this chart symbol

A

Danger line

  • A danger line draws attention to a danger which would not stand out clearly enough if represented solely by its symbol (e.g. isolated rock) or delimits an area containing numerous dangers, through which it is unsafe to navigate.
78
Q

Identify this chart symbol

A

Rock (Islet)

  • Which does not cover, height above the plane of reference for elevations
79
Q

Identify this chart symbol

A

Rock which covers and uncovers, with height known or unknown above chart datum

80
Q

Identify this chart symbol

A

Rock awas at chart datum

81
Q

Identify this chart symbol

A

Under rock of unknown depth, dangerous to surface navigation

82
Q

Identify this chart symbol

A

Underwater rock of known depth, not dangerous to surface navigation

83
Q

“Chart Datum”

A

Chart Datum is the reference point from which all depths and drying heights or lowest level of tide are measured on a nautical chart.

  • British Admiralty metric charts use lowest Astronomical Tide (LAT)
  • American charts use Mean Lower Low Water (MLLW)

Chart datum is defined as the level below which water seldom falls. Soundings refer to depths at datum.

84
Q

Charted Depth

A

The distance below chart datum of a feature is referred to as “Sounding”

85
Q

Drying Height

A

This is the height of an object or feature above chart datum; these features such as rocks or submerged objects may be uncovered at low water.

86
Q

Height of Tide

A

This is the height of the water above Chart datum and is found by using the tide tables to find high or low water and then applying the corrections derived from the appropriate tables.

87
Q

High Water

A

The time at which a tide reaches its maximum height. The tide tables predict the times that high and low water are expected to occur as well as the heights expected.

88
Q

Low Water

A

The time at which a tide reaches its minimum height

89
Q

Mean High Water (MHW)

A

This is the average height of high waters for a particuloar place: this average is worked out over a 19 year period. This is the point from which the height of structure such as bridges and lighthouses are measured.

90
Q

Mean Lower Low Water (MLLW)

A

The average of the lower low waters of each tidal day over a 19 year period. Used as Chart Datum on US and Canadian Charts. Using this datum, there will be often less water than is shown on the chart.

91
Q

How many feet in a nautical mile?

A

6076.12 feet

92
Q

How many nautical miles are in one minute of latitude?

A

1 Nautical Mile

93
Q

How many nautical miles are in one degree of latitude?

A

60 nautical miles

94
Q

A 10 tenth of a minute or a decimal minute degree of latitude is equal to what distance?

A

600 feet

185 meters

95
Q

What is Scale on a Chart?

A

A charts scale is the ratio of the distance on a chart to the distance on land or water.

  • A scale of 1:8000 means that the chart is one-eight thousandths of the size of the area it represents
  • Objects shown as a centimetre apart are physically 8000 centimetres (80 metres) apart
96
Q

List five items that appear in the title block of a chart

A
  1. Area of coverage
  2. Scale
  3. Projection
  4. Reference level for soundings
  5. Standard of measurement
97
Q

Two degrees, 15 minutes of latitude equal how many nautical miles

A

135 nautical miles

Each degree equals 60 nautical miles (60 + 60 = 120 NM)

Each minute equals 1 nautical mile (15 x 1 = 15 NM)

98
Q

Name 8 tools used on coastal navigation

A
  1. Compass
  2. Dividers
  3. Course plotter
  4. Parallel ruler
  5. Watch
  6. Hand held compass
  7. Depth sounder
  8. Knotmeter, pencil and eraser
99
Q

List six official publications, apart from charts, used by boaters.

A
  1. Chart 1
  2. NOTMARS
  3. Sailing Directions
  4. Small Craft Guides
  5. Tides and current tables
  6. Collision regulations
  7. Canadian aids to navigation
100
Q

What is the purpose of Notice to Mariners?

A

To update charts and marine publications and to draw attenon to new hazards

101
Q

List five factors to consider in preparing a passage or piloting plan.

A
  • Safe route
  • Shortest distance
  • Crew capability
  • Equipment
  • Hazards
  • Navigation methods
  • Tide and current
  • Weather conditions
102
Q

Indentify this chart symbol

A

Water Tower

103
Q

Identify this chart symbol

A

Rock which covers and uncovers with drying height

104
Q

Identify this chart symbol

A

Foul area dangerous to surface navigation

105
Q

Identify this chart symbol

A

Submarine cable

106
Q

Identify this chart symbol

A

Light flashing every 15 seconds, 85 ft high and visible from 15 nautical miles

107
Q

Identify this chart symbol

A

Sector light, fixed red showing arc of visibility, 36 metres high, visible for 11 nautical miles

108
Q

When proceeding out of a port in the IALA B region a green can marker must be kept to starboard or port?

109
Q

Explain the following light characteristic

Fl(3)12s44ft14M(U)

A

Light flashing in groups of three every 12 seconds. Height 44 feet and visible for 14 miles. Unattended

110
Q

Explain the following light characteristic

(VQ(6) + LF1)10s

A
  • Six very quick flashes follwed by a long flash, repeating every 10 seconds
  • South Cardinal Buoy
111
Q

Explain the following light characteristic

FlR

A
  • Flashing Red Light
  • Starboard Buoy (IALA B Region)
112
Q

What is the difference between Course, Heading and Bearing?

A
  • The direction a boat travels is its course
  • The direction a boat’s bow is pointed is its heading
  • A bearing is the direction of an object determined by a compass
113
Q

How do you calculate “Reciprocal Direction”

A
  • Add 180 if the intial direction is less than 180
  • Subtract 180 if the initial direction is more than 180
114
Q

What is the reciprocal of 085 degrees?

A

265 degrees

(085 + 180 = 265)

115
Q

T V M

248 9W

116
Q

A chart shows the following variation 021 E 1999 (8’W)

What variation to the nearest 1/2 degree should be used in 2012?

A
  • 13 years x 8’ = 104 minutes
  • 104 minutesy - 60 minutes = 1 degree 44 minutes
  • Variation = 021 E - 1 degree 30 minutes (rounded down to 1/2)
  • Variation = 019.5 E
117
Q

What causes compass deviation?

A
  • Ferrous metals & electrical devices
  • Examples include:
    • Anchor
    • Radio
    • Electrical wiring
    • Winches
    • Engine
    • Fuel tank
    • Holding tank
118
Q

Using the practice deviation table complete the following T-V-M-D-C conversion

T

V - 10W

M

D

C - 080

A

T = 076

V - 10W

M =086

D = 6E

C - 080

119
Q

Using the practice deviation table complete the following T-V-M-D-C conversion

T - 340

V - 15E

M =

D =

C =

A

T - 340

V - 15E

M =325

D = 0

C = 325

120
Q

Using the practice deviation table complete the following T-V-M-D-C conversion

T - 032

V =

M - 020

D =

C =

A

T - 032

V = 12E

M - 020

D = 4E

C = 016

121
Q

How do you label a plotted course line?

A

The plotted line is labled with the course direction preceded y C, for course. Put a space after the C

122
Q

If a boat’s speed is 5 knots how far will it go in 3 1/2 hours?

A

60D = ST

D = (S x T) / 60

D = (5kts x 210 min) / 60

D = 1050 / 60

D = 17.5 nm

123
Q

If a boat’s speed is 5 knots, how long will it take to cover 6 nm?

A

T = (60 x D) /S

T = (60 x D) / S

T= (60 x 6) / 5

T = (360) / 5

T = 72 min or 1h 12 min

124
Q

How fast is a boat cruising if it covers 14 nm in 1h 45m?

A

S = (60 x D) / T

S = (60 x D) / T

S = (60 x 14) / 105 min

S = (840) / 105

S = 8 kts

125
Q

What is navigating by dead reckoning?

A

Involves calculating a new position or positions from a known departure point using estimates of speed, course and elapsed time. The DR couse is plotted on the chart with a series of DR positions and may indicate the intended path of travel.

126
Q

What are the 5 rules for plotting a DR course?

A
  1. Start from a fix, that is a known departure point, and note the time
  2. Label the DR course in True degrees
  3. Use speed through the water (knotmeter) and teh 60D=ST formulae
  4. Plot the DR postion on the hour every hour and whenever there is a change in course and speed
  5. Follow labeling coventions
127
Q

What is the labeling convention for documenting a fix, course, speed and DR position on a chart?

A
  • A fix is plotted as a small circle with a dot in the centre
  • Course is placed above the plotted line and labeled with a C
  • Speed is placed below the line under the course
  • DR position are marked on the plotted course line with a semi-circle above the line with a small dot or short stroke at the centre
128
Q

How do you label a “Line of Position”

A
  • The time of the bearing is written above the line
  • The direction of the bearing is written below
129
Q

Estimated Position

A
  • Is plotted as a point inside a small square
  • A common way to upgrade a DR position to an EP positon is to use a bearing on a charted object.
  • DR positions can be off due to current, leeway and steering errors.
130
Q

Estimated Course

A
  • It is a new course after the navigator has figured out the estimated position.
131
Q

Two Bearing Fix

A

A second LOP, plotted from a bearing taken close to the same time as the first can provide a position of such accuracy as to be a fix. The boat’s position is the point where the two LOPs intersect.

This is a two-bearing fix

132
Q

Three Bearing Fix

Cocked Hat

A
  • To increase confidence in a two bearing fix a third bearing can be added.
  • The result is usually a small triangle of position known as a cocked hat.
  • The fix can be plotted in the centre of the triangle unless a hazard is nearby; then in which case you plot your position close to the hazard for the purposes of steering away from it.
133
Q

Clearing Bearings

A
  • A line of position that is plotted to avoid hazards
  • Its direction is noted along with whether, to clear the hazard, bearings taken on the object should be not more than (NMT) or not less than (NLT) the clearing bearing.
134
Q

Speed made good (SMG)

A

The spped over the botoom that results from combining the boat’s spped through the water with the current’s set and drift is called Speed mad good (SMG)

135
Q

Course made good (CMG)

A

In current the track a boat follows is a combination of its direction and speed combined with those of current. The set of a current can affect a boat’s course by pushing it left or right of the direction being steered. It can also speed up or slow down the boats progress.

136
Q

Finding Set and Drift

A
  • Plot a DR course from a fix
  • Establish a DR position at the same time as acquiring a fix
  • Draw a line representing the current from the DR position to the fix
  • Label the SET
  • Determine the distance in nautical miles using dividers
  • Determine the elapsed time in minutes since the previous fix and use the 60D=ST formula to find the speed of the current.
137
Q

Course to Steer

The Hour Diagram

Plotting Set and Drift

A

An hour diagram is the plotting technique used to find the course to steer and the speed made good. It takes into account the influence of the set and drift over one hour and applies it to the entire distance traveled.

  • The current vector is drawn from the point of departure in the direction of the currents set. Its length is the distance of the drift in one hour. For example, two knots of drift would be plotted as a vector two miles long.
138
Q

Course to Steer

Plot Course to Steer

A

A line is drawn from the end of the current vector to intersect the course to make good.

  • The length of the line is the speed of the boat over 1 hour
  • For example, if the boat is travelling 4 knots per hour then the distance is 4 nautical miles so you would take your dividers and meaure 4 minutes off the chart and draw a line.
139
Q

What are sector Lights ?

A

Sector lights, are directional lights that lead vessels through hazardous waters or narrow channels at night. These lights are used when approaching or leaving harbours.

140
Q

What are the three arcs of sector lights

A

Red sector – indicates the port side of the channel. The vessel needs to steer to starboard to return to the white sector.

Green sector – indicates the starboard side of the channel. The vessel needs to steer to port to return to the white sector.

White sector – indicates safe water.

141
Q

Geographic Range of Light

A

Lighthouse visibility is available on charts, both paper and digital, and is stated in terms of nominal range. This is the rating of the power of the light ad describes the distance at which the light will be seen in standard “clear” conditions.

142
Q

Nominal Range
Visual Range of ATON

A

The “Nominal Range” is the maximum distance at which a given light may be seen in “clear weather.” (Clear weather being defined as a meteorological visibility of 10 nautical miles).

The nominal range of any given light is shown on and can be read directly from nautical charts.

143
Q

Geographic Range
Visual Range of ATON

A

The “Geographic Range” is function of the curvature of the earth and is determined solely from the heights above sea level of the light itself and of the observers eye.

144
Q

What is the geographic range in navigation?

A

The maximum distance at which light from a light or other aid to navigation can reach an observer. It is limited by the curvature of the earth and refraction in the atmosphere and by heights of the observer and of the light or aid.

145
Q

Where can you find Geographic Range Tables?

A

Canadian Coast Guard List of Lights, Buoys and Fog Signals

United States Coast Guard Light List

146
Q

What is the Luminous Range?

A

The nominal range given in the Light List is the maximum distance a given light can be seen when the meterological visibility is 10 nautical miles. If the existing visibility is less than 10 NM, the range at which the light can be seen is reduced.

If the visibility is greater than 10 NM the light can be seen at a greater distance.

The distance at whic a light may be expected to be seen in the prevailing visibility is called its luminous range.

147
Q

What is the Geographic Range Nomogram?

A

By using the nomogram a geographical range can be determined by placing a straightedge against the height of the respective light and the height of the observer above water level.

148
Q

What is the nominal range diagram used for?

A

When a mariner obtains the meterological visibility from the weather report, he can find the distance the light can be seen at night from the nominal range diagram.

Example: the light list gives the nominal range 16 nautical miles. The weather report gives the meterological visibility 2 nautical miles. The point on the bottom of the diagram marked 16 is followed upwards until it intersects the curve marked 2 nautical miles.

Follow the height horizontally to the left margin to find that the visibility of the light is 5 nautical miles.

International Bareboat Skipper (7 decks)

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