How the Heck Can I Remember All of These Rules?

Ahh, the USCG Navigation Rules. Every mariner’s favorite topic – NOT.  They can be daunting to learn and remember and for many folks who use waterways they are completely unknown. However, anyone who ventures afloat on any vessel is responsible to know, understand and apply them. Even this last point is not known by most – what is a vessel? Well, there’s even a rule for that:

Rule 3(a)  – “The word “vessel” includes every description of watercraft, including non-displacement craft, WIG craft, and seaplanes, used or capable of being used as a means of transportation on water.”

So this includes kayaks, canoes, stand up paddleboards, you name it. While there is a legal requirement for all of these operators to abide by the Rules, they remain complex enough to be completely baffling so most folks don’t bother learning them.

Some mariners, including professionals and Coast Guard Auxiliary personnel, are required to prove their knowledge through testing and in some cases periodic retesting to maintain their qualification. This usually creates great anxiety, and folks will use flashcards and other tools to try to remember the various lights and shapes, conduct between vessels, etc. The good news is that, over the years, certain mnemonic aids have been developed and have stood the test of time to help remember the Rules. I learned many of them over 40 years ago while attending the Coast Guard Academy, and have learned a few more since then which I use when teaching the Rules to captain’s license candidates.

These aids are VERY helpful and are guaranteed to help boost the memory. Not every rule has a common memory aid – you just need to memorize the rules that don’t such as crossing situations between sailing vessels (starboard over port tack, leeward over windward) or between power driven vessels (vessel on the starboard side is the stand on vessel).  Or you can make up your own!

So, without further ado, here are some great memory aids for the Navrules.


CONDUCT OF VESSELS (In Sight of One Another)

There is a hierarchy of vessel types and who shall keep out of the way of the other. These are identified in Rule 18. Use this saying:



Overtaken Vessel


Not Under Command (NUC) – Broken


Restricted in Ability to Maneuver (RAM)


Constrained By Draft (CBD) – Int’l Only


Fishing Vessel


Sailing Vessel


Power / Towing Vessel




Overtaking Vessel

The higher up on the list, the more preference regarding stand-on vs. give-way.  For example, a power driven vessel shall give way to a sailing vessel and all those above it.


Certain vessels exhibit particular identification lights to help identify them or the nature of their work so that Rule 18 above can be applied properly.


Two Whites In A Row, A Tug And A Tow

Masthead lights when towing (all towing – astern, alongside or pushing ahead), tow length less than or equal to 200 meters, Int’l and Inland.

Three Whites In A Row, A Tug And A Long Tow

Masthead lights when towing astern, tow length greater than 200 meters, Int’l and Inland.

Yellow Over White, My Towline Is Tight

When towing astern, yellow towing light over sternlight, Int’l and Inland.

Only The Stern Light Will Show When Tug Touches Tow

One white sternlight on tug when towing alongside or pushing ahead, Int’l only!

No yellow.

Yellow Over Yellow, I’m a Pushing or Hip-Towing Inland Fellow

Two yellow towing lights on stern of tug when towing alongside or pushing ahead, Inland only! 

Note that only Inland Rules include the yellow special flashing light on the bow of the tow.


Red Over Green, Sailing Machine

Optional lights at the top of the mast for sailing vessels, Int’l and Inland.

Green Over White, Trawling At Night

Trawling at night, Show sidelights and sternlight only when making way.  Int’l and Inland.

Red Over White, Fishing At Night

Fishing at night, other than trawling. Show sidelights and sternlight only when making way.  Remember that TROLLING is NOT fishing.  Int’l and Inland.

Red Over Red, Captain (or Engine) is Dead

Vessel Not Under Command (NUC).  Show sidelights and sternlight if making way.  Int’l and Inland.

Red White Red, Restriction Ahead

Restricted in Ability to Maneuver (RAM).  Int’l and Inland

Go For The Green (or Go For The Diamonds)

Which side to pass a dredge.  Int’l and Inland.

Three Greens In A Cross, Mineclearing Boss

Mine clearance operations.  Int’l and Inland.

Three Reds In A Row, No Clearance Below

Constrained By Draft (CBD).  Int’l only.

White Over Red, Pilot Ahead

Pilotage duty.  Int’l and Inland.

It’s a bit tricky to remember the difference between vessels trawling and vessels fishing but NOT trawling.  A trawler drags a trawl (type of fishing net) at the sea bottom or midwater, and the gear tends to be deep.  Hence, a trawler’s gear can be thought of as a less risky fouling hazard and so their lights are green over white – but still a fishing vessel for the purposes of the Rules.

Fishing (Trawling)

Fishing (Other than Trawling)

Other types of fishing might include using longlines or gill nets that are miles long and at the surface.  Certainly more risky and thus “fishing other than trawling” have the red over white lights.  This is also why these vessels carry the black cone as a dayshape in the direction of gear extending more than 150 meters horizontally.

I sure hope these memory aids help you both when testing for your qualifications and also on the water too!