NAVIGATION-RELATED SYMBOLS, TERMS AND ABBREVIATIONS
1 The Sub-Committee on Safety of Navigation (NAV), at its fiftieth session (5 to 9 July 2004), agreed on Guidelines for the presentation of navigation-related symbols, given in annex 1, and terms and abbreviations, given in annex 2, and that they should be used for the display of navigation-related information on all shipborne navigational equipment and systems in consistent and uniform manner.
2 The Maritime Safety Committee, at its seventy -ninth session (1 to 10 December 2004), concurred with the Sub-Committee's views, approved the annexed Guidelines and encouraged their use for all shipborne navigational systems and equipment.
3 Member Governments are invited to bring the annexed Guidelines to the attention of all concerned.
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ANNEX 1
Guidelines for the Presentation of Navigation-related Symbols
1 Purpose
The purpose of these annexed guidelines is to provide guidance on the appropriate use of navigation-related symbols to achieve a harmonized and consistent presentation.
2 Scope
The use of these guidelines will insure that the symbols used for the display of navigation-related information on all shipborne navigational systems and equipment are presented in a consistent and uniform manner.
3 Application
These guidelines apply to all shipborne navigational systems and equipment. The symbols listed in the appendix should be used for the display of navigation-related information to promote consistency in the symbol presentation on navigational equipment.
The symbols listed in the Appendix should replace symbols which are currently contained in existing performance standards. Where a standard symbol is not available, another symbol may be used, but this symbol should not conflict with the symbols listed in the appendix.
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ANNEX 1
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APPENDIX
Navigation-related Symbols
Table 1: Own Ship Symbols
Topic
Symbol
Description
Double circle, located at own ship’s reference position.
Own ship
Use of this symbol is optional, if own ship position is
shown by the combination of Heading Line and Beam
Line.
Own Ship True
True scale outline located relative to own ship’s
reference position, oriented along own ship’s heading.
scale outline
Used on small ranges/large scales.
Own Ship Radar
Cross, located on a true scale outline of the ship at the
physical location of the radar antenna that is the current
Antenna Position
source of displayed radar video.
Own Ship Heading
Solid line thinner than the speed vector line style, drawn
to the bearing ring or of fixed length, if the bearing ring
line
is not displayed. Origin is at own ship’s reference point.
Own Ship Beam
Solid line of fixed length; optionally length variable by
line
operator. Midpoint at own ship’s reference point.
Dashed line – short dashes with spaces approximately
twice the line width of heading line.
Own Ship Speed
Time increments between the origin and endpoint may
optionally be marked along the vector using short
vector
intersecting lines.
To indicate Water/Ground stabilization optionally one
arrowhead for water stabilization and two arrowheads for
ground stabilization may be added.
Own Ship Path
A curved vector may be provided as a path predictor.
prediction
Thick line for primary source. Thin line for secondary
Own Shipsource.
Past Track
Optional time marks are allowed.
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Table 2: Tracked Radar Target Symbols
Topic
Symbol
Description
Solid filled or unfilled circle located at target position.
The course and speed vector should be displayed as
dashed line, with short dashes with spaces approximately
Tracked Target
twice the line width.
including
Optionally, time increments, may be marked along the
Dangerous Target
vector.
For a “Dangerous Target”, bold, red (on colour
display) solid circle with course and speed vector,
flashing until acknowledged.
Target in
Circle segments in the acquired target state.
For automatic acquisition, bold circle segments, flashing
Acquisition State
and red (on colour display) until acknowledged.
Lost Target
Bold lines across the circle, flashing until acknowledged.
Selected Target
A square indicated by its corners centred around the
target symbol.
Target Past
Dots, equally spaced by time.
Positions
Tracked Reference
R
Large R adjacent to designated tracked target.
Multiple reference targets should be marked as R1, R2,
Target
R3, etc.
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Table 3: AIS Target Symbols
Topic
Symbol
Description
An isosceles, acute-angled triangle should be used. The
AIS Target
triangle should be oriented by heading, or COG if
heading missing. The reported position should be
(sleeping)
located at centre and half the height of the triangle. The
symbol of the sleeping target should be smaller than that
of the activated target.
An isosceles, acute-angled triangle should be used. The
triangle should be oriented by heading, or COG if
heading missing. The reported position should be
located at centre and half the height of the triangle.
The COG/SOG vector should be displayed as a dashed
line with short dashes with spaces approximately twice
the line width. Optionally, time increments may be
Activated AIS
marked along the vector.
The heading should be displayed as a solid line thinner
Target
Including
than speed vector line style, length twice of the length of
Dangerous Target
the triangle symbol. Origin of the heading line is the
apex of the triangle.
The turn should be indicated by a flag of fixed length
added to the heading line.
A path predictor may be provided as curved vector.
For a “Dangerous AIS Target”, bold, red (on colour
display) solid triangle with course and speed vector,
flashing until acknowledged.
A true scale outline may be added to the triangle
symbol. It should be:
AIS Target – True
Located relative to reported position and according to
Scale Outline
reported position offsets, beam and length. Oriented
along target’s heading.
Used on low ranges/large scales.
Selected target
A square indicated by its corners should be drawn
around the activated target symbol.
Triangle with bold solid cross. The triangle should be
oriented per last known value. The cross should have a
Lost target
fixed orientation. The symbol should flash until
acknowledged.
The target should be displayed without vector, heading
and rate of turn indication.
Target Past
Dots, equally spaced by time.
Positions
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Table 4: Other Symbols
Topic
Symbol
Description
AIS Based AtoN
Diamond with crosshair centred at reported position.
Real Position of
(Shown with chart symbol. Chart symbol not required
Charted Object
for radar.)
AIS Based AtoN
Diamond with crosshair centred at reported position.
Virtual position
Monitored Route
Dashed bold line, waypoints (WPT) as circles.
Planned or
Dotted line, WPT as circles.
Alternate Route
Trial Manoeuvre
Large T on screen.
Simulation Mode
S
Large S on screen.
Cursor
Crosshair (two alternatives, one with open centre).
Range Rings
Solid circles.
Variable Range
Circle.
Additional VRM should be distinguishable from the
Markers (VRM)
primary VRM.
Electronic Bearing
Dashed line.
Additional EBL should be distinguishable from the
Lines (EBL)
primary EBL.
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ANNEX 1
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Topic
Symbol
Description
Acquisition/
Solid line boundary for an area.
Activation Area
Event Mark
Rectangle with diagonal line, clarified by added text