TEACHING SLIDES FOR

THEORY COURSES

CHARTWORK – PASSAGE PLANNING

BUOYAGE – FOG NAVIGATION

83 SLIDES

©

ROYAL YACHTING ASSOCIATION 2000

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ACKNOWLEDGEMENT

The RYA thank the publishers of the Macmillan Almanac and

the United Kingdom Hydrographic Office for their kind

permission to reprint some tables and diagrams contained in

these slides.

Slides compiled by

Jan & Michael Collings of Longbow Sail Training and Alison

Noice

COPYRIGHT

The information contained in slide 8 of this product is reproduced with

the permission of the Controller of Her Majesty’s Stationery Office and

the United Kingdom Hydrographic Office.

It may not be sold, either whole or in part, reproduced or transmitted in

any form or by any means, electronic, mechanical, photocopying,

recording or otherwise without prior permission of the Crown.

©

ROYAL YACHTING ASSOCIATION 2000

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CHART DESCRIPTION

ENGLAND - SOUTH COAST

MANACLE POINT TO BOLT HEAD

DEPTHS IN METRES

SCALE 1:150,000 at Lat 50 00

´

Depths are in metres and are reduced to Chart Datum, which is

approximately the level of Lowest Astronomical Tide.
Heights are in metres. Underlined figures are drying heights above

Chart Datum; all other heights are above Mean High Water Springs.
Positions are referred to World Geodetic Survey (1984)
Navigational marks: IALA Maritime Buoyage System - Region A

(Red to port).
Projection: Mercator.
Sources: The origin, scale, date and limits of the hydrographic

information used to compile the chart are shown in the Source

Data diagram.

©

ROYAL YACHTING ASSOCIATION 2000

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LATITUDE & LONGITUDE

Longitude (from
Greenwich)

Northern Hemisphere

Southern
Hemisphere

Equator

Latitud
e

Meridia
n

Longitud
e

Latitud
e

x

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ROYAL YACHTING ASSOCIATION 2000

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CHART PROJECTIONS

Transverse

Mercator

W

N

E

S

Longitud
e

Mercator

Latitud
e

Longitud
e

Used for Large Scale

charts

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ROYAL YACHTING ASSOCIATION 2000

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MERCATOR
PROJECTION

Distortion greater near

the polar region

Less distortion near the
equator

Longitud
e

Longitud
e

Latitude

Scale

Light

Source

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ROYAL YACHTING ASSOCIATION 2000

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VARIATION

Westerly
Variation
s

Easterly

Variations

Magnetic

North

Magnetic

South

T

T

M

T

M

True North
Pole

Magnetic

North Pole

©

ROYAL YACHTING ASSOCIATION 2000

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COMPASS ROSE

©

ROYAL YACHTING ASSOCIATION 2000

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MAGNETIC BEARINGS

True

North

Magneti

c

North

63°

71°

8

°

55

°

BEARING
Magnetic Bearing
071°
Variation
8°W
True Bearing
063°

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ROYAL YACHTING ASSOCIATION 2000

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MAGNETIC BEARINGS

True

North

Magnetic

North

63°

71°

8

°

55

°

BEARING
Magnetic Bearing
071°
Variation

8°W
True Bearing

063°

RELATIVE BEARING
Boat's heading

305° (T)

55° W of N

True Bearing 063° (T)
Relative Bearing 118° to
Starboard

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ROYAL YACHTING ASSOCIATION 2000

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DEVIATION

Similar in application to variation
Varies with boat's heading
Need a current Deviation Chart for each

fixed

compass on board
Not used with handbearing compass
(but need to check for gross errors)
Need to swing compass annually and

check

deviation occasionally

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ROYAL YACHTING ASSOCIATION 2000

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EFFECT OF COMPASS DEVIATION

N

S

W

E

N

S

W

E

N

S

W

E

N

S

W

E

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ROYAL YACHTING ASSOCIATION 2000

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000

090

270

360

180

045

135

225

315

2

4

6

0

2

4

6

West

East

Ship’s Head

Compass

(°C)

Deviation

Ship’s Head

Magnetic (°M)

000

4W

356

022.5

2W

020.5

045

0

045

067.5

2E

069.5

090

4E

094

112.5

5E

117.5

135

6E

141

157.5

5E

162.5

180

4E

184

202.5

2E

204.5

225

0

225

247.5

2W

245.5

270

4W

266

292.5

5W

287.5

315

6W

309

337.5

5W

332.5

360

4W

356

COMPASS DEVIATION TABLE

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MNEMONICS

“Error

W

est - Compass Best

Error

E

ast - Compass

Least”

NB Order and sign of corrections are

important

“

C

adbury's

D

airy

M

ilk

V

ery

T

asty +

E

xciting

(-

W

)”

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ROYAL YACHTING ASSOCIATION 2000

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APPLYING CORRECTIONS

T

rue Bearing

apply

D

eviation

M

agnetic

Bearing

apply

V

ariation

C

ompass

Bearing

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DEVIATION CHECK

True

North

N

S

W

E

305°(T)

Transit bears:
True 305°
Variation
8°W
Magnetic 313°
Compass 308°

DEVIATION 5°E

8

°

Magneti

c

North

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DEVIATION CONVERSIONS

Finding Course to
Steer

True Course (from chart) 060°(T)

Variation (from chart) 9°W

Magnetic Course 069°(M)

Deviation (from table) 2°E

Compass Course to Steer 067°(C)

Finding Course to
Plot

Compass Course Steered 240°(C)

Deviation (from table) 2° W

Magnetic Course 238°(M)

Variation (from chart) 8° W

True Course (to plot on chart) 230°(T)

23

0

°

24

0

°23

8°

060

°

06

7°

06

9°

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PLOTTING SYMBOLS

.

2
0

160
0

211
7

194
5

O
R

200
6

225
3

O
R

DR (Dead
reckoning)

EP (Estimated
position)

Fix (Observed
position)

Position
line

Transferred position
line

Range / Distance
of

Depth contour
line

Water
track

Ground
track

Tidal
stream

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ROYAL YACHTING ASSOCIATION 2000

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POSITION FIXING

THE THREE POINT

FIX

Perfect
fix

Cocked
hat

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ROYAL YACHTING ASSOCIATION 2000

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POSITION AND POSITION LINES

Position:

114°(T) from L/H 5M

OR

52°55'N 05°40'W

294°(T
)

114°(T)

Give Position FROM object

Take Fix
TO
object

Position Line

5°40'W

52°55'N

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ROYAL YACHTING ASSOCIATION 2000

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POTENTIAL FIX INACCURACIES - 1

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ROYAL YACHTING ASSOCIATION 2000

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POTENTIAL FIX INACCURACIES - 2

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FIX BY BEARING AND SOUNDING

Fi
x

1115

Log

1433

1115 Lighthouse bears
346

°

(T)

Depth 20 metres

20

20

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FIX BY DIPPING OR RISING LIGHT

Loom of light well

below horizon

Eye Level
2 metres

Geographical Range

Heig
ht
of
light
20m

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FIX BY DIPPING OR RISING LIGHT

Eye Level
2 metres

Geographical Range

Heig
ht
of
light
20m

Loom of light well

below horizon

Light just below horizon

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FIX BY DIPPING OR RISING LIGHT

Loom of light well

below horizon

Light just below horizon

Light breaks

horizon

(Rising Distance)

Eye Level
2 metres

Geographical Range

Heig
ht
of
light
20m

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ROYAL YACHTING ASSOCIATION 2000

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DIPPING DISTANCE TABLE

metres

1

2

3

4

5

metres feet

10

12

14
16
18

20
22

33

39

46
53

59

66

72

8.7

9.5

10.2

10.8

11.3

9.3

10.1

10.8

11.4

11.9

9.9

10.7

11.4

12.0

12.5

10.4

11.2

11.9

12.5

13.0

10.9

11.7

12.4

13.0

13.5

11.4

12.2

12.9

13.5

14.0

11.9

12.7

13.4

14.0

14.5

feet

3

7

10

13

16

Height of Eye

Height of

light

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DEAD RECKONING (DR)

The DR is deduced from:

1.

Course steered (taken from the

Compass)

2.

Distance run (from the distance

Log)

Dis

tan

ce r

un

6.2

mil

es

Fix
0800
25.1
M

Wat

er T

rack

070

°(T)

+

DR
0900
31.3
M

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ESTIMATED POSITION (EP)

DR Deduced from
Log and Compass

Distance
Run 6.2M

Fix
0800
25.1
M

Wat

er T

rack

070

°(T)

+

DR
0900
31.3
M

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ESTIMATED POSITION (EP)

.

Distance
Run 6.2M

DR Deduced from
Log and Compass

Fix
0800
25.1
M

+

Tidal
Stream

Estimated
Position
(No
leeway)
0900
31.3M

Wat

er T

rack

070

°(T)

DR
0900
31.3
M

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ESTIMATED POSITION (EP)

DR Deduced from
Log and Compass

Fix
0800
25.1
M

DR
0900
31.3
M

.

Tidal
Stream

Speed over ground

7.2 kn

Estimated
Position
(No
leeway)
0900
31.3M

Wat

er T

rack

070

°(T)

Ground Track 090°
(T)

+

Distance
Run 6.2M

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LEEWAY

Win
d

Water Track = Heading + or -
LEEWAY

Cou

rse

07

0°(

T)

Not

Plo

tte

d

Water Track
075°(T)
Course Plotted

Leeway 5°

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ROYAL YACHTING ASSOCIATION 2000

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ESTIMATED POSITION WITH

LEEWAY

Wind

Tidal Stream

075

°(

T)

5°

07

0°(

T)

090°(T)

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ROYAL YACHTING ASSOCIATION 2000

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TRANSITS

Nearing

transit

On

trans

it

Past

trans

it

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ROYAL YACHTING ASSOCIATION 2000

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FIX BY TRANSFERRED POSITION

LINE

USING ONE CHARTED FEATURE

1st Position
Line

+ D

R

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ROYAL YACHTING ASSOCIATION 2000

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1st Position
Line

Tidal
Strea
m

Wat

er

Trac

k

+D

R

FIX BY TRANSFERRED POSITION

LINE

USING ONE CHARTED FEATURE

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ROYAL YACHTING ASSOCIATION 2000

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1st Position
Line

Tidal
Strea
m

Wat

er

Trac

k

+D

R

2nd Position
Line

FIX BY TRANSFERRED POSITION

LINE

USING ONE CHARTED FEATURE

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ROYAL YACHTING ASSOCIATION 2000

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1st Position
Line

Tidal
Strea
m

Wat

er

Trac

k

+D

R

Fi
x

Transferred
Position
Line

2nd Position
Line

FIX BY TRANSFERRED POSITION

LINE

USING ONE CHARTED FEATURE

©

ROYAL YACHTING ASSOCIATION 2000

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FIX BY TRANSFERRED POSITION

LINE

USING TWO CHARTED FEATURES

.

+

D
R

1st Position
Line

Wat

er

Trac

k

Tidal
Strea
m

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ROYAL YACHTING ASSOCIATION 2000

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+

D
R

1st Position
Line

Wat

er

Trac

k

Tidal
Strea
m

2nd Position
Line

FIX BY TRANSFERRED POSITION

LINE

USING TWO CHARTED FEATURES

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ROYAL YACHTING ASSOCIATION 2000

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.

+

D
R

Wat

er

Trac

k

Tidal
Strea
m

Fi
x

Transferre
d
Position
Line

RUNNING FIX

2nd Position
Line

1st Position
Line

FIX BY TRANSFERRED POSITION

LINE

USING TWO CHARTED FEATURES

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ROYAL YACHTING ASSOCIATION 2000

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COURSE TO STEER (CTS)

EP
0800
25.1
M

Win
d

Tidal Stream

150°(T)

.

Ground Track

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COURSE TO STEER (CTS)

EP
0800
25.1
M

Tidal
Stream

Tidal Stream

150°(T)

.

Ground Track

Win
d

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COURSE TO STEER (CTS)

Ground Track

EP
0800
25.1
M

Tidal
Stream

Wat

er T

rack

Tidal Stream

150°(T)

.

Win
d

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COURSE TO STEER (CTS)

EP
0800
25.1
M

Tidal
Stream

Allo

wan

ce

for

Lee

way

7°

Tidal Stream

150°(T)

Wat

er T

rack

.

Ground
Track

Win
d

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ESTIMATED TIME OF ARRIVAL (ETA)

Duration of Passage = 4.4 x 60min = 52min
5.1

ETA = 0800 + 0052 = 0852

.

Ground Track

0800
25.1
M

Distance to Destination 4.4M

Distance Capability in 1 Hour 5.1M

Tidal Stream

150° (T)

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COURSE SHAPING - WIND

STRATEGY

Tide

Cherbourg to
Salcombe

Port

or

Starboard

Tack?

Tack on Tide Change

This maximises relative

wind

Known as “ Lee-bowing ”

Win
d

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ROYAL YACHTING ASSOCIATION 2000

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COURSE SHAPING

Tide

Get on any natural transit and steer

into tide to stay on it

Course to

be made

good

PORT ENTRY - CROSS TIDE

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COURSE SHAPING

PORT ENTRY - CROSS TIDE

When close enough to see, transfer to more

appropriate transit until out of tide

Tide

Course to

be made

good

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ROYAL YACHTING ASSOCIATION 2000

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STRATEGY ON APPROACH TO HARBOUR

If wind shifts, you

are never far of

course

Tack when approx.

15°

either side of track

to destination

Wind

©

ROYAL YACHTING ASSOCIATION 2000

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LEADING LINES

1

9

2

°(

T

)

Keep lights in line

on

192°(T) for transit

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LEADING LINES AND LIGHTS

Leading

Lights

in line 215°(T)

As
seen

Spire and

Cone

in line

210°(T)

Ld

g

L

ts

2

1

5

º(

T

)

As
charted

S

p

ir

e

a

n

d

c

o

n

e

i

n

l

in

e

2

1

0

°(

T

)

+

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BEARINGS

1

9

2

°(

T

)

Keep buoy on

228°(T)

until leading lights

are in transit

228

°(T)

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ROYAL YACHTING ASSOCIATION 2000

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CLEARING BEARINGS

No less

than

162°(T)

No greater

than 190°(T)

+

+

+

+

+

+

Beacon
Tower

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CARDINAL MARKS

Continuous

Flashing

3 Flashes

6 Short + 1
Long

9
Flashes

2
Flashes

DANGER

Safe

Wate

r

Safe

Wate

r

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LATERAL AND OTHER BUOYAGE

MARKS CAN BE BUOYS OR ON POSTS
COLOUR DEFINES PURPOSE

Port Hand

Any R except (2 +

1)

Special Marks

Yellow, any rhythm

except used for

white lights

Starboard Hand

Any G except (2 +

1)

Safe Water

Iso, Occ,
L Fl 10s or

Mo(A)

KEEP TO

PORT

OR

STARBOARD

Direction

of

Buoyage

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LATERAL AND OTHER BUOYAGE

Starboard Hand

Any G except (2 + 1)

Preferred Channel

to Stbd Fl (2 + 1)R

Port Hand

Any R except (2 + 1)

Safe Water

Iso, Occ,

L Fl 10s or Mo(A)

Special Marks

Yellow, rhythm not

used for white lights

Preferred Channel
to Port Fl (2 + 1)G

Direction

of

Buoyage

KEEP TO

PORT

OR

STARBOARD

MARKS CAN BE BUOYS OR ON POSTS
COLOUR DEFINES PURPOSE

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RHUMB LINE SAILING

Great
Circle

Rhumb
Line

Mercator
Projection

Gnomonic
Projection

Great
Circle

Rhumb
Line

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PASSAGE PLANNING

Define objective

Constraints on operation

Crew, time available etc

Assemble navigation equipment

Charts, Pilots, Tide Tables and

Tidal Stream Atlases

Plan provisions (including emergency

stock)

Personal kit

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Constraints on departure - locks, sills?

If so - departure time is set within

these limits -

Plan

FORWARD

Constraints on arrival - locks, sills?

If so - arrival time is set between these

limits -

Plan

BACKWARDS

Passage constraints - races, strong tides?

If so - transit time is set by the

phenomenon

If more than one constraint

Plan waiting period when appropriate

PASSAGE PLANNING

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Calculate distance and expected

passage time

Calculate times between waypoints

for high

speed navigation

Plan for departure/arrival by day/night

Plan for optimum use of tide

Plan waypoints

Is fuel capacity adequate for passage?

If not, plan refuelling stops

PASSAGE PLANNING

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Determine possible visual aids on the

route

By day - buoys, headlands etc.
By night - lights, glow from towns etc

.

Prepare pilotage notes for departure,

entry and

ports of refuge

Listen to forecasts over several days to

determine

possible wind directions and sea states

PASSAGE PLANNING

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Departure constraints?

Bar especially at Spring Ebb & strong
onshore winds

Arrival constraints?

None - but difficult in strong SE to SW

winds

Transit constraints?

None, but avoid overfalls of Start Point

and drying area on Skerries Bank

Distance 19 miles, approx.

4 hours @ 5 kn. / 2 hours @ 10 kn.

PASSAGE PLAN

Salcombe to Dartmouth

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Departure

Local HW ± 4½ hrs - Take advantage of tidal

streams

Plan waypoints

Salcombe Bar
South of Prawle Point
Overfalls of Start Point
2½ Miles W of Skerries Point LH
Dartmouth Entrance

Visual aids

Start Point LH, Skerries Point LH
Port Hand Mark NW of Skerries Bank
Churches and Masts on Shore

PASSAGE PLAN

Salcombe To Dartmouth

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Ports of Refuge

Anchorage N of Start Point for SW Winds

(Avoid overfalls and Skerries Bank)

Anchorage in Holcombe Bay for NW to NE winds

Crew considerations

Clothing
Experience
Food/drinks en route
MOB Drill

Weather information

Before start and under way

PASSAGE PLAN

Salcombe to Dartmouth

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PASSAGE PLAN

Plymouth to Guernsey

Departure constraints

None - but beware of Naval activities and ferries
Care in strong South and West winds
Take departure from Eddystone Rock LH

Arrival constraints?

Sill (Entry/exit up to ± 2½ hours local HW)

Transit constraints?

Shipping Lanes (Not Separation Scheme)
Through Race of Alderney, Swinge or via Casquets?
Through Little or Big Russel Channels or West of

Guernsey?

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Distance 58 Miles Approx

12 hours @ 5 knots

3 hours @ 20 knots

Departure

Time departure to arrive at Race of

Alderney

at appropriate time

Visual aids

Mast on Rame Head
EC 'A' Buoy, Eddystone Rocks LH
Quenard Point LH, Cap de la Hague LH
Platte Fougère LH, Bec du Nez LH

PASSAGE PLAN

Plymouth to Guernsey

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PASSAGE PLAN

Plymouth to Guernsey

Plan waypoints

Plymouth West Breakwater

East of Eddystone Rocks LH
Start and end of shipping

lanes

Top of Race of Alderney
West of Banc de la Schôle
Lower Heads South

Cardinal

Weather information

Before start and under way

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PILOTAGE

(Navigating Safely in Confined

Waters)

USE ALL SIGNPOSTS AVAILABLE

Buoys & lights
Charted landmarks
Transits, clearing bearings
Soundings etc.

PRE-PLAN

Use large scale charts
Pilot books
Local knowledge
As detailed as necessary for the task

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PILOTAGE

DETAIL NEEDED

Start of pilotage

Distance and Course to Steer to next

mark

Use 6 minute marks for high speed

navigation

Repeat until destination

reached

Use transits and clearing bearings
to avoid hazards

©

ROYAL YACHTING ASSOCIATION 2000

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LOG EXTRACT

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ROYAL YACHTING ASSOCIATION 2000

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GLOBAL POSITIONING SYSTEM



US Military system –

selective availability

discontinued in 2000



Based on 24 satellites



10,900 mile high orbits



24 hour coverage



Satellite gives spherical position line



4 Satellites give 3 dimension fix

©

ROYAL YACHTING ASSOCIATION 2000

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GLOBAL POSITIONING SYSTEM

(GPS)

©

ROYAL YACHTING ASSOCIATION 2000

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GPS - FIX ERROR

Position
Spheres

©

ROYAL YACHTING ASSOCIATION 2000

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ELECTRONIC NAVIGATION AIDS



Position

Latitude & Longitude
Bearing and distance



Course and speed

over
ground



Bearing and

distance to

next Waypoint



Cross track error



ETA



Waypoint entry



Sailplan / Routes



Tracks between

waypoints



Satellites/transmitters

available



Transmitter selection



Datum & Altitude

selection



Variation correction



Position correction



Battery voltage

©

ROYAL YACHTING ASSOCIATION 2000

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WAYPOINTS AND SAILPLAN

Star
t

Port of

Refuge

1

2

3

4

5

6

7

Destinati
on

©

ROYAL YACHTING ASSOCIATION 2000

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WAYPOINTS AND SAILPLAN

Star
t

1

2

3

4

5

6

7

Port of

Refuge

Destinati
on

©

ROYAL YACHTING ASSOCIATION 2000

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WAYPOINTS AND SAILPLAN

Star
t

1

2

3

4

5

6

7

Port of

Refuge

Destinati
on

©

ROYAL YACHTING ASSOCIATION 2000

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FOG NAVIGATION

Planned T

rack - G

ood Visib

ility

5

10

20

5

10

20

©

ROYAL YACHTING ASSOCIATION 2000

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FOG NAVIGATION

5

10

20

5

10

20

Po

or

V

is

ib

ilit

y T

ra

ck

©

ROYAL YACHTING ASSOCIATION 2000

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OFFSHORE FOG NAVIGATION

Objecti
ve

10

Circle of

D
R

20

Uncertain
ty

©

ROYAL YACHTING ASSOCIATION 2000

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OFFSHORE FOG NAVIGATION

Objecti
ve

10

Circle of

D
R

20

Uncertain
ty

©

ROYAL YACHTING ASSOCIATION 2000

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OFFSHORE FOG NAVIGATION

Objecti
ve

10

Circle of

D
R

20

Uncertain
ty