Rules of the Road

1
Rules of the Road

• Able Requirement 14

2
Able Requirement 14

• Explain and demonstrate a working knowledge of
  the nautical rules of the road that govern the
  local waters used by your ship's principal craft.
  
• Explain and demonstrate ship's lights, rules in
  limited visibility, whistle signals, and right of
  way, including exceptions vessels.
• Describe special lights and day shapes deployed
  on the following vessels not under command
  restricted by ability to maneuver constrained by
  draft fishing (trawling) sailboat.
• Reference
• See "Rules of the Road" on page 174.
• Navigation Rules (International - Inland),
  COMDTINST M16672.2D

3
Inland Navigation Rules Act of 1980

• 1-3 General Rules
• 4-19 Steering and Sailing Rules
• 4-10 apply in any condition of visibility
• 11-18 apply to vessels in sight of one another
• 19 apply to vessels in restricted visibility
• 20-31 Lights and Shapes
• 32-37 Sound and Light Signals
• 38 Exemptions

4
Application(Rule 1)

• These Rules apply to all vessels...
• International
• ...upon the high seas and in all waters connected
  therewith navigable by seagoing vessels.
• Inland
• ...upon the inland waters of the U.S. and to U.S.
  vessels on Canadian waters of the Great Lakes.
• Importance (prevent collision, prevent loss of
  life, etc..)
• Rules apply according to location - Inland vs.
  International
• Difference between the COLREGS and Inland Rules
  as determined by boundaries described in
  Navigation Rules
• Rules of the Road are mandatory,
• COLREGS contains no penalty for violations while
  the Inland Rules provide for a penalty for
  vessels navigated in violation of the rules
• Obedience must be timely

5
Responsibility(Rule 2)

• Nothing in these rules shall exonerate any
  vessel, operator or owner from the consequences
  of
• neglect to comply with these rules
• neglect of any required precaution
• special circumstances of the case
• A departure from these rules may be necessary to
  avoid immediate danger.

6
General Definitions(Rule 3)

• Vessel - every description of watercraft capable
  of being used for transportation on the water
• Power-driven vessel - any vessel propelled by
  machinery.
• Sailing vessel - any vessel under sail provided
  any propelling machinery is not being used.
• Vessel engaged in fishing
• nets, lines, trawling (not trolling)
• Vessel not under command (NUC)
• Vessel restricted in her ability to maneuver
  (RAM)
• laying, servicing, retrieving navigation aids,
  cables, pipeline
• dredging, surveying, underwater ops
• towing which restricts ability to deviate from
  course
• Vessel constrained by her draft (International
  only) (CBD)

7
General Definitions - Vessels(Rule 3)

• Underway - not at anchor or made fast to shore or
  aground.
• Vessels in sight of one another - only when one
  can be observed visually from the other.
• Restricted visibility - any condition in which
  visibility is restricted by fog, mist, falling
  snow, heavy rainstorms, sandstorms or any other
  similar causes.
• Inland Waters navigable waters of the U.S.
  shoreward of the demarcation lines dividing the
  high seas from harbors and other inland waters.

8
Important Terms

• These terms are defined in detail by Rules 16 and
  17
• Give-way - a term used for the vessel which is
  directed by rule to keep out of the way.
• Stand-on - a term used for the vessel which is
  directed by rule to keep its course and speed.
• May take action if other vessel is not taking
  appropriate action
• Shall take action if necessary to avoid collision

9
Steering and Sailing Rules(Rules 4-19)

• Rules 4-19 apply in any condition of visibility.

10
Proper Look-Out Required (Rule 5)

• Every vessel shall at all times maintain a proper
  look-out by sight and hearing as well as by all
  available means appropriate in the prevailing
  circumstances and conditions to make a full
  appraisal of the situation and of risk of
  collision.

11
Safe Speed(Rule 6)

• Every vessel shall proceed at a safe speed so
  that it can take proper and effective action to
  avoid collision and be stopped within a distance
  appropriate to the prevailing circumstances and
  conditions.

12
Safe Speed(Rule 6)

• In determining a safe speed the following factors
  shall be taken into account
• Visibility
• Traffic density
• Maneuverability including stopping distance and
  turning ability in the prevailing conditions
• At night the presence of background light
• Wind, sea, current, and proximity of hazards
• Draft in relation to depth of water
• Additional factors for vessels with radar.

13
Risk of Collision(Rule 7)

• Every vessel shall use all available means
  appropriate to the prevailing circumstances and
  conditions to determine if risk of collision
  exists.
• If there is any doubt, such risk shall exist.
• Proper use shall be made of radar equipment if
  fitted and operational, to obtain early warning
  of risk of collision.
• Assumptions shall not be made.

14
Risk of Collision(Rule 7)
RELATIVE BEARING(Angle to other vessels)DOES
NOT CHANGE
In determining if risk of collision exists
Such risk shall exist if the compass bearing
of an approaching vessel does not appreciably
change.
15
Risk of Collision(Rule 7)
RELATIVEBEARINGSCHANGING
Close quarters situation less likely. Risk of
collision may not exist, but assumptions should
not be made.
16
Risk of Collision(Rule 7)

• In determining if risk of collision exists
• Such risk may exist even when a bearing change
  is evident, particularly when approaching a very
  large vessel or a vessel at close range.

17
Action to Avoid Collision (Rule 8)

• Action taken to avoid collision shall be
  positive, made in ample time and with regard to
  good seamanship.
• Alteration of course or speed shall be large
  enough to be readily apparent to another vessel.
  
• Alteration of course alone may be the most
  effective action to avoid a close-quarters
  situation if made in good time.

18
Action to Avoid Collision (Rule 8)

• Action taken shall result in passing at a safe
  distance.
• If necessary, a vessel shall slacken speed or
  take all way off by stopping or reversing means
  of propulsion.

19
Narrow Channels(Rule 9)

• A vessel in a narrow channel shall keep as near
  to the outer limit of the channel on its
  starboard side as is safe and practicable.

20
Narrow Channels(Rule 9)

• A power vessel proceeding downbound with a
  following current shall have right-of-way over an
  upbound vessel.

CURRENT
21
Narrow Channels(Rule 9)

• A vessel less than 20 meters in length or a
  sailing vessel shall not impede a vessel that can
  safely navigate only within a channel.

22
Narrow Channels(Rule 9)

• A vessel engaged in fishing shall not impede
  passage of any other vessel navigating within a
  narrow channel.

23
Narrow Channels(Rule 9)

• A vessel shall not cross a narrow channel if such
  crossing impedes passage of a vessel that can
  safely navigate only within a channel.

24
Narrow Channels(Rule 9)

• An overtaking vessel shall indicate its intention
  by sounding the appropriate signal and take steps
  to permit safe passing. The overtaken vessel
  sounds same signal if in agreement.

TOOT TOOT
TOOT
25
Narrow Channels(Rule 9)

• A vessel nearing a bend or an area where vessels
  may be obscured by an obstruction shall navigate
  with particular alertness and caution and sound
  appropriate signals.

3
5
6
TOOOOOOOOT
TOOOOOOOOT
4
7
1
2
8
26
Narrow Channels(Rule 9)

• Every vessel shall avoid anchoring in a narrow
  channel.

27
Narrow Channels(Rule 9)

• Vessels leaving a dock, slip, tie-up or mooring
  shall yield the right-of-way to all vessels
  approaching.

GIVE-WAY
STAND-ON
MOORING BUOY
GIVE-WAY
28
Application of Rules(Rule 11)

• Rules (11-18) apply to vessels in sight of one
  another.

29
Sailing Vessels(Rule 12)

• When two sailing vessels are approaching, one of
  them shall keep out of the way as follows When
  each has the wind on a different side, the vessel
  with the wind on the port side shall keep out of
  the way.

WIND DIRECTION
PORT
STARBOARD
STAND-ON
GIVE-WAY
30
Sailing Vessels(Rule 12)

• When both have the wind on the same side, the
  vessel which is to windward (upwind) shall keep
  out of the way of the vessel which is to leeward
  (downwind).

WIND DIRECTION
PORT
GIVE-WAY
WINDWARD LEEWARD
PORT
STAND-ON
31
Sailing Vessels(Rule 12)

• When both have the wind on the same side, the
  vessel which is to windward (upwind) shall keep
  out of the way of the vessel which is to leeward
  (downwind).

WIND DIRECTION
STARBOARD
GIVE-WAY
STARBOARD
WINDWARD LEEWARD
STAND-ON
32
Sailing Vessels(Rule 12)

• If a vessel with the wind on port side sees a
  vessel to windward and cannot determine if the
  other vessel has the wind on the port or
  starboard, it shall keep out of the way.

WIND DIRECTION
?
PORT
LINE OF SIGHTDifficult to determine which side
sail is on
GIVE-WAY
33
Sailing Vessels(Rule 12)

• The windward side is opposite to the side the
  mainsail is carried on.

WIND DIRECTION
PORT
STARBOARD
WINDWARD
WINDWARD LEEWARD
LEEWARD
MAINSAIL
HEADSAIL
MAINSAIL
HEADSAIL
34
Overtaking(Rule 13)

• Any vessel overtaking any other shall keep out of
  the way of the vessel being overtaken.

STAND-ON
GIVE-WAY
35
Overtaking(Rule 13)

• A vessel shall be overtaking when coming up from
  a direction more than 22½ degrees abaft (behind)
  another vessels beam

CROSSING ZONE
OVERTAKING ZONE135º
STAND-ON
HEAD-ON
CROSSING ZONE
in a position that at night it would only see the
stern light but neither of the sidelights of that
vessel.
36
Overtaking(Rule 13)

• When a vessel is in any doubt as to whether it is
  overtaking, it shall assume it is and act
  accordingly.

OVERTAKING or CROSSING?
?
?
37
Overtaking(Rule 13)

• When a vessel is in any doubt as to whether it is
  overtaking, it shall assume it is and act
  accordingly.

DANGER ZONE
OVERTAKING
CROSSING
?
?
38
Head-On Situation(Rule 14)

• Unless otherwise agreed, when two power-driven
  vessels are meeting on reciprocal courses each
  shall alter course to starboard so that each
  shall pass on the port side of the other.

STARBOARDPORT
PORTSTARBOARD
GIVE-WAY
39
Head-On Situation(Rule 14)

• Such a situation shall exist when a vessel sees
  the other ahead or nearly ahead and by night it
  could see both sidelights and by day observes the
  corresponding aspect.
• When a vessel is in any doubt as to whether such
  a situation exists it shall assume that it does
  exist and act accordingly.

40
Crossing Situation(Rule 15)

• When two power-driven vessels are crossing, the
  vessel which has the other on its starboard side
  shall keep out of the way and shall avoid
  crossing ahead of the other vessel.

STAND-ON
GIVE-WAY
ALTER COURSE, SLOW or STOP
41
DANGER ZONE
112.5º
STAND-ON
112.5º
Observes green sidelight of approaching vessel
GIVE-WAY
Observes red sidelight of vessel in danger zone
42
Crossing Situation(Rule 15)

• A vessel crossing a river shall keep out of the
  way of a power-driven vessel ascending or
  descending.

RIVERCURRENT
GIVE-WAY
43
Action by Give-Way Vessel(Rule 16)

• Every vessel which is directed to keep out of the
  way of another vessel shall, so far as possible,
  take early and substantial action to keep well
  clear.

44
Action by Stand-On Vessel(Rule 17)

• Where one of two vessels is to keep out of the
  way, the other shall keep its course and speed.
• The stand-on vessel may take action as soon as it
  becomes apparent the give-way vessel is not
  taking appropriate action.
• A power-driven vessel which takes action with
  another power vessel shall not alter course to
  port for a vessel on its own port side.
• When the stand-on vessel finds itself so close
  that collision cannot be avoided by the give-way
  vessel alone, it shall take action to avoid
  collision.

45
Responsibilities Between Vessels(Rule 18)

• Except where Rules 9 (Narrow Channels), 10
  (Traffic Schemes) and 13 (Overtaking) otherwise
  require
• A power vessel underway shall keep out of the way
  of
• a vessel not under command
• a vessel restricted in its ability to maneuver
• a vessel engaged in fishing (commercial vessel)
• a sailing vessel

46
Responsibilities Between Vessels(Rule 18)

• A sailing vessel shall keep out of the way of
• a vessel not under command
• a vessel restricted in its ability to maneuver
• a vessel engaged in fishing (commercial)
• A vessel engaged in fishing (commercial) shall
  keep out of the way of
• a vessel not under command
• a vessel restricted in its ability to maneuver

47
Conduct in Restricted Visibility(Rule 19)

• This rule applies to vessels not in sight of one
  another when in or near an area of restricted
  visibility.
• Every vessel shall proceed at a safe speed
  adapted to the conditions. Power vessels shall
  have engines ready for immediate maneuver.
• Every vessel shall have due regard to the
  prevailing conditions when complying with
  navigation rules.

48
Conduct in Restricted Visibility(Rule 19)

• A vessel which detects another vessel by radar
  shall determine if risk of collision exists. If
  so, it shall take avoiding action.
• Every vessel which hears the fog signal of
  another shall reduce speed to the minimum at
  which it can be kept on course. It shall if
  necessary take all way off and, in any event,
  navigate with extreme caution.

49
Lights and Shapes(Rules 20-31)

• 20-22 - General
• 23 - Power-driven Vessels Underway
• 24 - Towing and Pushing
• 25 - Sailing Vessels Underway and Vessels Under
  Oars
• 26 - Fishing Vessels
• 27 Vessels Not Under Command or Restricted in
  Their Ability to Maneuver
• 28 Vessels Constrained by Their Draft
• 29 Pilot Vessels
• 30 Anchored Vessels and Vessels Aground
• 31 Seaplanes

50
Application(Rule 20)

• Same for Intl and Inland
• Rules (20-31) shall be complied with in all
  weathers
• The rules concerning lights apply from sunset to
  sunrise and periods of reduced visibility
• No other lights shall be shown, except such
  lights as cannot be mistaken for the lights
  specified in these Rules or do not impair their
  visibility or distinctive character, or interfere
  with the keeping of a proper look-out.
• The rules concerning shapes shall be complied
  with by day.

51
Definitions(Rule 21)

• Masthead light 225, white
• Sidelights 112.5, green/red
• Stern light 135, white
• Towing light 135, yellow
• All-around light 360
• Flashing light 120/min

52
Visibility of Lights(Rule 22)

• gt 50 meters (gt161 feet)
• Masthead 6 nm
• Sidelights, sternlight, towing light, all-around
  3 nm
• Special flashing (Inland) 2 nm
• 12-49 meters (39.4-161 feet)
• Masthead 5 nm
• Sidelights, sternlight, towing light, all-around
  2 nm
• Special flash (Inland) 2 nm

• lt12 meters (39.4 feet)
• Masthead 2nm
• Sidelights 1 nm
• Sternlight /towing light/all-around 2nm
• Special flashing (inland) 2nm
• Partially submerged vessel or object being towed
• White all-around light 3nm

53
Power-Driven Vessels Underway (Rule 23)

• gt 50 Meters
• Masthead
• single, as forward as practical
• Second light abaft and higher
• Sidelights
• Sternlight

54
Power-Driven Vessels Underway (Rule 23)

• lt 50 Meters
• Masthead
• single, as forward as practical
• Sidelights
• Sternlight

55
Power-Driven Vessels Underway (Rule 23)

• lt 12 Meters
• Single all-around
• Sidelights
• lt 7 meters and lt 7 knots
• single all-around white

56
Power-Driven Vessels Underway (Rule 23)

• Air-cushion vessel
• Non-displacement mode single all-around
  flashing yellow light above stern light
• Displacement mode same as power-driven vessel

57
Towing and Pushing (Rule 24)

• Tow length gt 200 m astern
• 3 masthead lights in a row
• sidelights
• sternlight
• yellow towing light above sternlight
• diamond day shape

58
Towing and Pushing (Rule 24)

• Tow length lt 200 m astern
• 2 masthead lights in a row
• sidelights
• sternlight
• yellow towing light above sternlight

59
Towing and Pushing (Rule 24)

• A composite unit is a vessel pushing another
  vessel that are rigidly connected to form a
  single vessel.
• Gets same lights as a power-driven vessel
• gt50m two masthead lights
• lt 50m single masthead light
• sidelights
• sternlight

60
Towing and Pushing (Rule 24)

• A vessel towing alongside or pushing varies for
  international versus inland
• International loses yellow sternlight and tow
  is automatically less than 200m
• Inland changes white sternlight into yellow
  two yellow sternlights but tow is automatically
  less than 200m

61
Towing and Pushing (Rule 24)

• Towed Vessel gt 200m
• Lights are always the same
• Adds a diamond dayshape
• Towed Vessel lt 200m
• Lights are always the same

62
Towing and Pushing (Rule 24)

• For a vessel being pushed ahead that is not part
  of a composite unit
• FOR INTERNATIONAL, just like a towed vessel
  unless being pushed ahead then no sternlight
  which would blind the pushing vessel

63
Towing and Pushing (Rule 24)

• For a vessel being pushed ahead that is not part
  of a composite unit
• FOR INLAND, just like a towed vessel EXCEPT it
  adds a flashing yellow light to front of pushed
  vessel.

64
Sailing Vessels Underway and Vessels Under Oars
(Rule 25)

• Vessels under sail and ONLY under sail are
  sailing vessels.
• Sailing vessels USING motorized propulsion
  engines are considered under power.
• Vessels under sail or oars have the right of
  way over vessels under power
• Sailing vessels need only sidelights and a stern
  light. For vessels under 20m, these may be
  combined into a single tricolor masthead light.

65
Sailing Vessels Underway and Vessels Under Oars
(Rule 25)
66
Sailing Vessels Underway and Vessels Under Oars
(Rule 25)

• In addition, sailing vessels may add an all-round
  red light above an all-round green light on the
  mast.
• Red over green, sailing machine

67
Sailing Vessels Underway and Vessels Under Oars
(Rule 25)

• Under 7m, vessels just need a way to make light
  (e.g., a flashlight)
• Same for sailing and oar-driven

68
Sailing Vessels Underway and Vessels Under Oars
(Rule 25)

• During daytime, a sailing vessel under power
  exhibits a triangle dayshape pointed down
• During nighttime, the sailing vessel under power
  just uses power driven vessel lights

69
Fishing Vessels (Rule 26)

• Trawling vessels have an all-round green over
  all-round white masthead light.
• Notice that these masthead lights are all-round,
  not arcs
• Green over White, Trawling at Night

70
Fishing Vessels (Rule 26)

• Fishing vessels have an all-round red over
  all-round white masthead light.
• Notice that these masthead lights are all-round,
  not arcs
• Red over White, Fishing at Night
• Fishing versus trawling? Really its the gear
  being used but its the same thing.
• A trawler will use nets and more often travel in
  pairs at each end of the net.

71
Vessels Not Under Command or Restricted in
Ability to Maneuver (Rule 27)

• Vessels not under command meaning without means
  to alter course due to equipment failure have
  right of way over vessels restricted in ability
  to maneuver.
• Red over red, captain is dead
• Two all-round red lights in a vertical line where
  they can best be seen
• When making way through the water, in addition to
  the red over red lights, sidelights and a
  sternlight.
• Two balls or similar shapes in a vertical line
  where they can best be seen

72
Vessels Not Under Command or Restricted in
Ability to Maneuver (Rule 27)

• A vessel restricted in ability to maneuver
• Red, White, Red, Restricted Ability Ahead
• red over white over red all-round lights in a
  vertical line where they can best be seen
• three shapes in a vertical line where they can
  best be seen the highest and lowest of these
  shapes are balls and the middle one is a diamond

73
Vessels Not Under Command or Restricted in
Ability to Maneuver (Rule 27)

• With Towing...
• Towing lights plus restricted in ability to
  maneuver
• Note that towing does not by itself automatically
  constitute a restriction in ability to maneuver!
  The tow must limit the towing vessels ability to
  maneuver

74
Vessels Not Under Command or Restricted in
Ability to Maneuver (Rule 27)

• Vessel engaged in dredging or underwater
  operations
• Safe side is indicated by 2 green lights/2
  diamond dayshape.
• Obstruction side is indicated by 2 red lights/2
  ball dayshape

75
Vessels Not Under Command or Restricted in
Ability to Maneuver (Rule 27)

• Mine-clearers are considered restricted in
  ability to maneuver during performance of their
  duties.
• They also get a special lighting configuration
  and dayshape.
• Three greens in a cross, mine-clearing boss.
• Hint Avoid these!

76
Vessels Not Under Command or Restricted in
Ability to Maneuver (Rule 27)

• Vessels having divers over the side also exhibit
  a flag. Military/commercial vehicles use the
  Alpha flag while civilian ships use an
  alternative
• Diving is usually done during the day, so there
  is no special nighttime light configuration other
  than the restricted in ability to maneuver

77
Vessels Constrained by Their Draft(Rule 28)

• INTERNATIONAL ONLY!!
• Vessels restricted in maneuvering due to their
  draft have a special restricted in ability to
  maneuver status that puts them between not
  under command and restricted in ability to
  maneuver
• Three red lights or a cylinder dayshape

78
Pilot Vessels(Rule 29)

• Pilot vessels vessels that carry a person
  (pilot) more knowledgeable in the local area
  have an all-round white light over an all-round
  red light to indicate pilot duties.
• White over red, pilot ahead
• Note again these are all-round lights
• No dayshape The word Pilot on the hull usually
  covers the dayshape
• Treated as a normal power driven vessel

79
Anchored Vessels and Vessels Aground(Rule 30)

• A vessel at anchor will display an all-round
  white light if under 50m or an all-round white
  light at each end if greater than 50m in length.
• If greater than 200m in length, the vessel must
  also use reasonably available means to illuminate
  its deck
• Dayshape is a single ball

80
Anchored Vessels and Vessels Aground(Rule 30)

• Vessels aground cant move so they are not
  under command AND at anchor.
• Two red lights for not under command and white
  lights for being at anchor
• Two balls for not under command plus one ball for
  at anchor three balls in a line.

81
Seaplanes(Rule 31)

• Seaplanes will have lighting similar to other sea
  vessels to the extent allowed by their shape.

82
The Rule of the Road

• When all three lights I see ahead,I turn to
  Starboard and show my RedGreen to Green, Red to
  Red,Perfect Safety -- Go Ahead.
• But if to Starboard Red appear,It is my duty to
  keep clear --To act as judgment says is
  properTo Port or Starboard, Back or Stop her.
• And if upon my Port is seenA Steamer's Starboard
  light of Green,I hold my course and watch to
  seeThat Green to Port keeps Clear of me.
• Both in safety and in doubtAlways keep a good
  look out.In Danger, with no room to turn,Ease
  her, Stop her, Go Astern.

• GREEN To GREEN, RED To RED - Perfect Safety Go
  Ahead
• Yellow Over White Tow Line Is Tight
• Red Over Green - Sailing Machine
• Green Over White - Trawling At Night
• Red Over White - Fishing At Night
• Red Over Red, The Captain Is Dead
• Red, White, Red, Restricted Ability Ahead
• Three Reds In A Row -No Room Below
• Three Greens In A Cross Mine-clearing Boss
• White Over Red - Pilot Ahead

83
Sound and Light Signals(Rules 32-37 )

• 32-33 General
• 34 Maneuvering and Warning Signals
• 35 Sound Signals in Restricted Visibility
• 36 Signals to Attract Attention
• 37 Distress Signals

84
Definitions(Rule 32)

• A whistle is a sound signaling device capable
  of producing the required sounds. Most Navy
  vessels use air-powered whistles as opposed to
  electronic speakers
• A short blast (SB) is one second duration
• A prolonged blast (PB) is 4 to 6 seconds duration
• If activated manually, most people undercount the
  elapsed time. Use a watch to count seconds.

85
Equipment(Rule 33)

• A vessel under 100m in length needs a whistle and
  a bell.
• A vessel over 100m in length needs a whistle, a
  bell, and a gong.
• Whistle is for sounds while underway
• Vessels in reduced visibility use the ships
  whistle to indicate their presence
• Bell (and gong) is for sounds while at anchor or
  aground
• Vessels at anchor use the ships bell (and gong)
  to indicate their presence

86
Maneuvering and Warning Signals(Rule 34)

• International sound signals meeting or crossing
• 1 short blast I am altering my course to
  starboard
• 2 short blasts I am altering my course to port
• 3 short blasts I am operating astern
  propulsion.

• Inland sound signals- meeting or crossing
• 1 short blast I intend to leave you on my port
• 2 short blasts I intend to leave you on my
  starboard
• 3 short blasts I am operating astern
  propulsion
• Answer same signal or 5 short blasts
• Similar light signals may be used as supplements
  to the sound signals

87
Maneuvering and Warning Signals(Rule 34)

• Inland sound signals- overtaking
• 1 short blast I intend to overtake you on your
  starboard
• 2 short blasts I intend to overtake you on your
  port
• Answer same signal or 5 short blasts
• International sound signals - overtaking
• 2 prolonged, 1 short blast I intend to overtake
  you on your starboard
• 2 prolonged, 2 short blasts I intend to overtake
  you on your port
• Answer 1 prolonged, 1 short, 1 prolonged, 1
  short
• Uncertainty - a vessel uncertain as to another
  vessels intentions or is fearful that a
  collision will occur will sound 5 short blasts
• Blind bend 1 prolonged
• Leaving dock - a power-driven vessel will sound 1
  prolonged blasts

88
Sound Signals in Restricted Visibility(Rule 35)

• Power driven vessel making way shall sound at
  intervals of not more than 2 minutes 1 prolonged
  blast
• Power driven vessel underway but not making way
  shall sound at intervals of not more than 2
  minutes 1 prolonged- 2 sec 1 prolonged
• The following vessels shall sound at intervals of
  not more then 2 minutes 1 prolonged, 2 short
• not under command
• restricted in maneuverability (either underway or
  at anchor)
• constrained by draft
• sailing
• engaged in fishing (either underway or at anchor)
  
• engaged in towing or pushing

89
Signals to Attract Attention(Rule 36)

• Any light or sound signals that cannot be
  mistaken for any signal authorized elsewhere in
  the rules
• Assume anything abnormal is a distress call.
  i.e., signal from rule 36 is probably rule 37

90
Distress Signals(Rule 37)