NAVIGATION
IN
PRACTICE
INTRODUCTION
CHENG CHING SIANG
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B.Sc (Biology) from NUS
M.A. (Southeast Asian Studies) from NUS
Bridgewatchkeeping Certificate awarded by
the Republic of Singapore Navy
Watchkeeping Certificate level 1 awarded
by the Federal Republic of Germany Navy
INTRODUCTION
The views and opinions expressed in
this session are purely personal and do
not in any way represent any official
view of the Republic of Singapore Navy
or any Government body.
SCOPE
PREPARING A PASSAGE
COASTAL NAVIGATION
OCEAN PASSAGE
Q & A session
Right: Parkes Radio
Space Telescope
in Australia
PREPARING A PASSAGE
Getting Organized
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PUBLICATIONS
 Admiralty Sailing Directions, Admiralty Distance Tables,
Admiralty list of Lights, Admiralty Tide Tables etc.
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CHARTS
 Largest Scale Charts appropriate for the purpose
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METEOROLOGY
 Likely Weather, Weather Stations en route
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PILOTS
 Diversionary Ports, Search and Rescue alternatives
PREPARING A PASSAGE
Planning the ETD and ETA
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Tidal Considerations, Port Restrictions, Courtesies
to the Country visited etc.
Fuel considerations
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Economical Steaming
PREPARING A PASSAGE
All is not always plain sailing!
COASTAL NAVIGATION
FIXING METHODS
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Visual
Radar
Horizontal/Vertical Sextant Angle
Combination
Radio Fixing
GPS/DGPS
COASTAL NAVIGATION
An Example of
Fixing using
Sounding Lines
& Bearing
COASTAL NAVIGATION
Bearing Lattice Fixes
COASTAL NAVIGATION
Lattice of HSA curves
COASTAL NAVIGATION
PILOTAGE
OCEAN PASSAGE
Celestial Navigation
Modern Methods i.e. GPS, LORAN-C, DECCA
Dead Reckoning
OCEAN PASSAGE
Celestial Navigation
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Planning
Pointers
Other Practical Uses
 Gyro Checks
Fig : Evening Twilight by Sergon
 Prediction of Phenomenon like Sunrise/Sunset,
Moonrise/Moonset, Twilight etc.
OCEAN PASSAGE
Modern Methods
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Global Positioning Systems
Right: A GPS
Satellite
OCEAN PASSAGE
Modern Methods
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Others
 Inertial Navigation System (INS)
 Navigation Sensor System Interface (NavSSI)
 Bottom Contour Navigation
 Long Range Navigation
Right: Tomahawk Firing
during the Gulf War
OCEAN PASSAGE
Dead Reckoning
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Loosely defined as the plotting of the Ship’s
approximate position or future position
A fix is something in History
Fig : A Dead Reckoned Track
LOST PROCEDURES
I have a few suggestions
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Get on MMS Ch 16 and yell for help
Ask a passing ship politely in as many
languages possible for a GPS position
Get your spare GPS working
Get that sextant out
Right: An International
Distress Flag ‘SOS’
BON
VOYAGE!