Rules of the Road

[MarinersSchool]

Rule #7 states that a vessel needs to be "approaching", that is, getting closer to each other. Second, the compass bearing of the other vessel must be constant or near constant. When in a constant bearing, decreasing range situation, a collision is inevitable if neither of the two vessels maneuvers. If the compass bearing with the other vessel is constant, the passing distance or closets point of approach (CPA) will be zero.

If the bearing is changing, the CPA will be somewhat further apart. The faster the rate of bearing change, the greater the passing distance will be.

It is important to note that risk of collision may still exist even if the bearing is changing, especially when the two vessels are in close proximity to each other.

This rule directs you to use all available means including your eyes, stationing lookouts, electronic devices (such as VHF radio and radar), and any other operational or mechanical procedures (such as taking frequent bearings) that may help determine if a risk of collision does exist.

Many vessels are not equipped with common navigational devices including compasses, radar, depth finder, etc. that are in good working order. You should recognize all of the possible dangers that could exist and be especially alert to any approach between vessels at a close range. The bearing of an approaching vessel should be determined and monitored by frequent visual observation.

Rule #7 - Risk of collision also recognizes that radar can be deceiving and that a person observing the radar, especially an untrained observer, can make mistakes. Other means such as maintaining effective lookouts, bridge-to-bridge radio communications, and soundings while listening for timely fog signals may provide better information on the presence, course, and speed of another vessel.

Making radar plots of the relative positions of other vessels in the area is not required if the resulting information is meaningless. This may be the case in winding channels or in close conditions in a river or canal. In many cases plotting would be of little value to small vessels.
__________________
Captain Bob Figular
President, Mariners School

 

[MarinersSchool]

Any action you take to avoid a collision must be taken early enough to be effective and must be large enough to be readily apparent to the other vessel.

Changing course is generally better than changing speed due to the fact that this would be more immediately obvious to the other vessel. A course change great enough to be obvious would have the additional benefit at night of displaying different navigation lights. Rule #8 specifically advises against making a series of small course or speed changes that may not be easily detected by other vessels.

At all times your vessel's course may not be a straight line. Limitations imposed by a narrow and winding channels, shallow water, or ice conditions may force you to hold a course dictated by the limits of the channel. These limitations may restrict you to making only small course changes to avoid other dangers, such as running aground.

All actions taken to avoid collision should result in passing at a safe distance. Therefore, you must carefully check the effectiveness of your actions until the other vessel finally passes you and is clear.
__________________
Captain Bob Figular
President, Mariners School

 

[MarinersSchool]

A channel is considered to be a safe route between hazards, or a deeper route through shallow or shoaling water. A channel is considered to be "narrow" when the boats operating in it are severely limited in their ability to maneuver.

A fairway is the thoroughfare between docks and piers in a harbor or marina. In general you are required to to stay out of narrow channels or fairways that are heavily traveled by large ships and tugs.

Here are some general rules as the pertain to narrow channels and fairways:

1) Stay as close as possible to the starboard side.
2) Sailboats, fishing boats, and boats of less than 20 meters should stay out of the way of vessels confined to operating safely in the channel.
3) Do not cross the channel if it will interfere with a boat confined in the channel.
4) Do not anchor in a channel.
5) Sound a prolonged (four to six second) blast when approaching a bend or other obscured area. Boats approaching in the opposite direction are required to answer with the same signal.

 

[MarinersSchool]

Traffic Separation Schemes (TSS) are inbound and outbound traffic lanes, divided by separation lines or zones, and are printed on charts using magenta ink.

Their purpose is to provide one-way lanes for large ships and other commercial traffic into and out of major ports. Between the traffic lanes and any adjacent land masses, you will usually find inshore traffic zones (labeled as such on your chart).

Sailboats, fishing boats, and all boats under 20 meters are free to use these inshore traffic zones, and in any case, are to stay clear of any ship using a traffic lane. If you cross a traffic lane, do so quickly, far away from other vessels, and at right angles to the flow of traffic.

It is important to note that vessel traffic services, found only in the Inland Rules, are roughly equivalent to traffic separation schemes.

 

[MarinersSchool]

Since an overtaking vessel is likely to be slower and, thus less able to get out of the way, an overtaking vessel must give-way by maintaining its course and speed.

If the other vessels sidelight is visible at the same time as its sternlight, then the situation is a crossing, rather than an overtaking situation.

During the day, without the benefit of the other vessel's navigation lights, it may be hard to determine whether you are overtaking, since the 22.5 degrees aft-of-the-beam bearing is defined relative to the beam of the overtaking vessel, not that of the overtaking boat. For this reason Rule #13 states that, when there is any doubt, a vessel is required to assume that she is in an overtaking situation.

During the overtaking evolution, the overtaking boat will pull forward of the overtaking sector. For this reason, Rule #13 states that an overtaking boat continues to be the give-way boat until she is past and clear of the overtaken boat.

It is important to note that just because an overtaking vessel is required with keeping out of the way of an overtaken vessel, Rule #13 does not give sailboats, boats of less than 20 meters in length, and fishing vessels the right to impede the passage of an overtaking boat in a narrow channel or fairway. However, the overtaking vessel must first obtain agreement from the overtaken boat and take whatever precautions she can make the overtaking safe.

 

[MarinersSchool]

Rule #14 Head-on Situations applies only to powerboats, not to vessels that are sailing, fishing, restricted-in-ability-to-maneuver (RAM), or not-under-command (NUC).

This rule also uses the phrase "so as to involve risk of collision." Although the Rule states that boats meeting head-on should pass port-to-port, this does not mean that you can never pass starboard-to-starboard. Before a risk of collision exists, either boat can alter course so long as the course change requires no subsequent action by the other vessel.

Once a risk of collision does exist, or when the boats are within a half-mile of each other U.S. Inland Rules state that the boats must indicate their maneuvers or intent to maneuver with the signals indicated in Rule #34. They may agree to pass starboard-to-starboard, but they should have a good reason to do so.

It is increasingly common under the Inland Rules for boats to signal their intentions via VHF radio, referring to a port-to-port pass as "one whistle" and a starboard-to-starboard pass as "two whistles." This may be acceptable between professional mariners but is very dangerous between weekend boaters, since some skippers do not understand the meanings and may be reluctant to admit it in front of their passengers. In the interest of safety, pass port-to-port whenever possible and indicate your intentions in those words.

 

[MarinersSchool]

Here is a breakdown of Rule #15 - Crossing Situation and what it means

Note that Rule #15 applies only:
1) to two boats, not three or more;
2) to power-driven vessels (not to boats sailing, fishing, not-under-command, or restricted in their ability to maneuver);
3) in crossing (not head-on or overtaking) situations;
4) after risk of collision has been determined to exist.

Before risk of collision can be established, either boat is free to maneuver at will. Once risk of collision has been established, however, the boat with the other vessel approaching on her starboard side:
1) becomes the give-way vessel
2) must not cross ahead of the stand-on boat unless circumstances require it.

Remember that a boat approaching on your starboard side sees your green (go) navigational light while a boat approaching on your port side sees your red (stop) navigation light.

Before crossing a narrow channel or fairway, remember rule #9, "A vessel shall not cross a narrow channel or fairway if such crossing impedes the passage of a vessel which can only navigate safey only within such channel or fairway.

Similarly, when you are in a traffic seperation scheme, Rule #10 states, "A vessel of less than 20 meters in length... shall not impede the safe passage of a power-driven vessel following a traffic lane"

A power boat underway, but not making way through the water, has no special rights. So in the event that she is approached by another power-driven vessel from dead ahead to 22.5 degrees abaft her starboard beam, then she is required by the rules to get some way on and get out of the way!

 

[MarinersSchool]

Rule #16 simply states that a Give-way vessel must take significant and obvious action in ample time (before the Stand-on vessel begines to question your intent). The alteration of course or speed must be large enough to be obvious to the other vessel. At night, for example, the change of course should be large enough to show a different navigational light. It is important to never make a series of small course changes.

Give enough room, alterations to course are usually preferable to alterations in speed because course changes are more apparent from the other vessel. Once again, at night, the course change in a meeting or crossing situation should be large enough to display your opposite bow light; ie., swing your bow past the stand-on vessel.

 

[MarinersSchool]

Rule #17 - Action of the Stand-On Vessel applies only where a risk of collision exists between two (not three or more) vessels. In such a situation, the boat required to keep out of the way is the "give-way vessel" (Rule 16). Rule 17 covers the other vessel, the stand-on vessel."

The actions required by the stand-on vessel can be broken down into four steps:

1) Before risk of collision exists, either vessel is free to maneuver at will.
2) Once risk of collision exists, except to avoid hazards, the stand-on vessel must maintain its course and speed.
3) If it becomes apparent to the stand-on vessel that the give-way vessel is not taking the appropriate (early and substantial) action to keep out of the way, then the stand-on vessel MAY take action to avoid collision. If both boats are power driven, however, the action must not turn to port for a give-way vessel on her port side. Any maneuvers she makes must be accompanied by the appropriate maneuvering signal. If she chooses not to maneuver, then she should sound the danger signal (five short blasts on the whistle). If the give-way vessel can be readily identified by either name, characteristics, or location, then a call on VHF CH13 or 16 would also be appropriate.
4) If the situation should deteriorates to the point where a collision can no longer be avoided by the action of the give-way vessel alone, the stand-on vessel MUST to take the best action it can to avoid collision.

 

[MarinersSchool]

The Navigational Rules of the Road establishes a "pecking order" between different types of vessels. A vessel higher than you on the list is considered to be the ""stand-on" vessel in a collision situation; vessels below you are considered to be the "give-way" vessel. The list, in order of decreasing rights:

Not Under Command (NUC)
Restricted in Ability to Maneuver (RAM)
Constrained by Draft (CBD)
Fishing Vessel
Sailing Vessel
Power Driven Vessel
Seaplane

Example: A sailboat (powered by sail alone) must keep out of the way of vessels engaged in fishing, constrained by draft, restricted in ability to maneuver, and not under command (all of the vessel types above it in this list), but not ordinary power driven vessels or seaplanes.

To claim special status, a boat must display the appropriate lights or day shapes. Therefore, a fishing boat not displaying fishing or trawling lights or dayshapes and a tug not displaying the lights or dayshapes for a vessel restricted in her ability to maneuver are simply considered power-driven vessels.