NS100

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NS100

• Fundamentals of
• Naval Science

Inland Rules of the Road IV
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Objectives
1. Know the day shapes displayed by all vessels
(Rule 23 - 30). 2. Know the requirements for
seaplanes in compliance with the regulations
(Rule 31). 3. Know internationally recognized
distress signals.
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Day Shapes (Rule 24-30)
1. Towing w/ length of tow gt200m Diamond 2.
Vessel being towed w/ length of tow gt200m
Diamond 3. Sailing vessel under power Conical
shape apex down 4. Fishing vessel Two cones
with apexes together - fishing lt20m may
display a basket from the mast - when gear
extends past 150m, display a cone apex up.
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Diamond
Basket
Conical shape apex down
Conical shape apex up
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Diamond
Fishing
Towing gt200m
Basket
Tow, length of tow gt200m
Fishing lt20m
Conical shape apex down
Conical shape apex up
Sailing vessel under power
gear extends past 150m
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Day Shapes (Rule 24-30)
5. Trawling vessel Two cones with apexes
together - trawling lt20m may display a
basket from the mast 6. Not Under Command Ball
over Ball 7. Restricted in Ability to Maneuver
Ball/Diamond Ball 8. Vessel at Anchor
Ball 9. Dredging Ball/Diamond/Ball, diamond
over diamond on side that is clear, ball over
ball on obstructed side.
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Ball
Ball
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Trawling, lt20m
Trawling
Ball
Ball
Restricted in ability to maneuver
Not under command
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Diamond
Diamond
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Vessel at Anchor
Dredging
Engaged Side Unengaged Side
Diamond
Diamond
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Day Shapes (Rule 24-30)
10. Diving Operation Rigid international Code
Alpha 11. Mine sweep Ball on mast/ball on each
end of the fore yardarm (triangle) 12.
Vessel aground Ball/ball/ball 13. Vessel
Constrained by draft Cylinder (only
International)
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Rigid Code Alpha
Ball
Ball
Cylinder
Ball
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Rigid Code Alpha
Diving
Aground
Mine Sweeping
Ball
Ball
Cylinder
Constrained by Draft
Ball
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Anchored Vessels and Vessels Aground (Rule 30)
1. Vessels at anchor shall display one all around
white light where it can best be seen. a. Pilot
vessels may leave their task lights on when
anchored. b. Vessels over 50m in length must
exhibit one all around white light forward,
and one all around white light aft (at a
lower level than the forward light). c.
Vessels over 100m must illuminate their decks
with lights
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Anchored Vessels and Vessels Aground (Rule 30)
lt 50m
gt 50m
gt100m
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Anchored Vessels and Vessels Aground (Rule 30)
gt 50m
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Seaplanes (Rule 31)
1. Seaplanes will comply with lighting as closely
as possible when its characteristics make normal
compliance impracticable.
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Signals to Attract Attention (Rule 36)
1. If necessary to attract attention of another
vessel, a vessel may make any signal that cannot
be mistaken for the signals in these rules. She
may direct her searchlight in the direction of
danger in such a way as not to embarrass any
vessel.
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Distress Signals (Rule 37)
1. When a vessel is in distress and requires
assistance, she shall use or exhibit the signals
described below a. Red star shells b. Black
ball and square in orange background c. Dye
marker d. Radio telegraph e. Fog horn sounding f.
SOS ( --- )
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Distress Signals (Rule 37)
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Distress Signals (Rule 37)
1. When a vessel is in distress and requires
assistance, she shall use or exhibit the signals
described below g. Code flags November
Charlie h. Radio telephone I. Flames on vessel j.
Mayday by radio k. Square flag and ball l.
Position indicating alarm radio beacon
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Distress Signals (Rule 37)

• Radio-Telephone Alarm
• Mayday by radio
• Position Indicating Beacon

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Distress Signals (Rule 37)
1. When a vessel is in distress and requires
assistance, she shall use or exhibit the signals
described below m. Gun fired at 1 minute
intervals n. Parachute red flare o, Wave arms
over head p. Smoke q. A high intensity white
flashing light at regular intervals from 50 - 70
flashes (Inland rules only).
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Distress Signals (Rule 37)
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QUESTIONS?