Sailors are notorious for having poor memories, perhaps due to the copious amounts of rum they have imbibed. Whatever the reason, over the years they have developed memory tools that aid in information retention and these aids are called mnemonics. The most well known sailor’s mnemonic is ‘new reels catch fish so purchase some’. It encapsulates Rule 18 of the International Rules for Preventing Collisions at Sea (IRPCS). That rule which is an otherwise dry affair, denotes the order of the priority of vessels that must give way to other vessels, based on their maneuverability. These responsibilities between vessels, as the rule is formally known, require a set of definitions to determine the pecking order of what vessels are less maneuverable than others.
COLREGS Rule 3 Definitions:
Power-driven vessel means any vessel propelled by machinery.
Sailing vessel means any vessel under sail provided that propelling machinery, if fitted, is not being used.
Vessel engaged in fishing means any vessel fishing with nets, lines, trawls or other fishing apparatus which restricts maneuverability, but does not include a vessel fishing with trolling lines.
The word seaplane includes any aircraft designed to maneuver on the water.
Vessel not under command means a vessel which through some exceptional circumstances is unable to maneuver – to keep out of the way of another vessel.
Vessel restricted in her ability to maneuver means a vessel which from the nature of her work is unable to keep out of the way of another vessel. The term shall include but not be limited to: 1) a vessel engaged in laying, servicing or picking up a navigation mark, submarine cable or pipeline, 2) a vessel engaged in dredging, surveying or underwater operations, 3) a vessel engaged in replenishment or transferring persons, provisions or cargo while underway, 4) a vessel engaged in launching or recovery of aircraft, 5) a vessel engaged in mine clearance operations, and 6) a vessel engaged in a towing operation such as severely restricts the towing vessel and her tow in their ability to deviate from their course.
The term vessel constrained by her draft means a power-driven vessel which, because of her draft in relation to the available depth and width of navigable water is severely restricted in her ability to deviate from the course she is following.
With the definitions of these vessels in hand, Rule 18 can be distilled into a few phrases, triggered by an association with key words that are easy to remember:
New: Not under command
Reels: Restricted in her ability to maneuver
Catch: Constrained by draft
Fish: Engaged in fishing
As far as fishing vessels are concerned, the responsibilities between vessels rule is interpreted as commercial vessels in the process of fishing and does not include personal recreational boats that are fishing. However, a full-day charter sport fishing boat trolling for billfish is also excluded from the rule (even though the captain is being paid to operate the sport fish and is considered a commercial vessel), as it is trolling at eight or nine knots and is considered maneuverable.
In the 1960s, the Soviet Union developed Wing-In-Ground-Effect (WIG) craft for military purposes, and they were brought into operational use in the 1979. These waterborne aircraft fly at close proximity to the water by utilizing surface-effect action in the same manner that a pelican does as it glides a foot or two above the bay. For Russian military use, the first WIG craft were very fast troop transports and assault craft. Today, a very small variety of WIG craft are available for the recreational pilot and are usually in kit form. The IMO added Wing-In-Ground to the lexicon of Rule 18 in 2001 stating: A WIG craft shall, when taking off, landing and in flight near the surface, keep well clear of all other vessels and avoid impeding their navigation. This language is similar to that of the requirements for seaplanes.
One anomaly in the vessel priority rule is the difference between the international waters version of the rule and the U.S. inland waters version. The category of a vessel constrained by draft does not exist in the inland rules. A large fully loaded container ship entering Port Everglades at Fort Lauderdale could be considered constrained by draft while entering the navigation channel after it passes the safe water mark. But once it passes across the COLREGS inland demarcation line and is inside the rock jetty channel, the ship is no longer considered constrained by draft even though the depth and width of the channel have not changed.
Most sailors are also familiar with the unwritten ‘gross tonnage rule’, that is, if a vessel is bigger than you are, keep out of its way. Even so, a day sail around a busy harbor may convince you that there are still a few die-hard sailors who are willing to risk the effect of a ship’s steel plating scraping against the fiberglass hull and the rigging of a small sailboat. A word to the wise is sufficient.