Top 101 Boating Facts and Factoids

The Official Cheat Sheet From Boating’s College of Nautical Knowledge

There’s a lot to know in this sport we call boating. Too much, in fact. Which is good, as it keeps us interested and constantly learning. And it’s also bad, as there’s always something you should have known and only figured out later-usually, when it was too late. So class, here’s this semester’s lessons. Read on. Then take notes, and highlight the good parts. You never know when life will throw you a pop quiz.

Here’s the Pitch

An engine should run within its recommended rpm operating range at wide open throttle. If it revs below the range, less prop pitch is called for. If it’s above the range, more pitch is required. Props are described by diameter first, then pitch. Thus a 14½” x 19″ prop has a diameter of 14½” and a pitch of 19″.


Pecking Order

Whichever type of vessel is higher on this list has the right of way over those below it.

• Vessel not under command


• Vessels restricted in maneuverability

• Vessels engaged in fishing

• Sailboats


• Powerboats

Speed Freak

Hull speed for a displacement boat can be computed using the following formula:


V = the square root of LWL x 1.34

V = velocity in knots

LWL = waterline length

Left, Right, Left, Right

A single-engine boat with a right-handed prop backs to port.

With a left-handed propeller, the boat backs to starboard.

Do Not Pass Go

When two boats under power are about to meet head-on, neither has the right-of-way. Both vessels must make a noticeable course alteration to starboard after giving the proper signal of one short blast. When two vessels under power are crossing, the boat that has the other to starboard is the give-way vessel and must avoid the other by passing astern. The privileged vessel should maintain course and speed.

Half Time

When visibility is restricted, hold to a speed that allows you to stop in no more than half of the distance of your visibility.

Down a Lazy River

A power-driven vessel operating in a narrow channel on the Great Lakes or in western rivers and proceeding downstream with a following current, has the right-of-way over an upbound vessel.

Twice as Nice

If you have two similar lines and the second is twice as thick as the first, the second line will be four times stronger than the first.

Found Horizons

Distance to your radar’s horizon in nautical miles can be estimated with the following formula: 1.23 x the square root of H = Distance H = the height of the radome in feet

Near or Far

To determine the distance to any object, use the following formula:

D + 1.17 x the square root of H = Distance

D = distance to the horizon in nautical miles (see above)

H = eye height above sea level in feet

Use this formula twice. Once to calculate the distance to the geographic horizon, and once to calculate the object’s distance off. Add the two to get the total distance off for the object.


A tall person (6’2″ and up) generally requires 3’2″ of sitting headroom. A person of average height (5’8″) needs 2’11”.

Who Needs NOAA?

Often, you can see the approach of a front or squall on radar, usually with the unit set on the 6- or 12-mile range.


Tide is highest at the full new moon.

‘Tis Hurricane Season

June, too soon;

July, stand by;

August, look out!

September, you will remember.

October, all over.

Rhyme Time

Weather Sayings:

Red sky at night, sailors delight.

Red sky at morning, sailors take warning.

When a halo rings the moon or sun,

rain will come upon the run.

Mackerel skies and mares’ tails,

make tall ships carry low sails.

(Cirrus clouds, which resemble mackerels and the wisps of a horse’s tail, indicate approaching storms.)

Block Out

The American Cancer Society recommends using a sunblock with on SPF of 15. Recent studies have shown that the advantages of increasing SPF above 15 may not increase the effectiveness correspondingly.

Send a Wire

When fishing, to calculate the depth to which solid wire line sinks while trolling, count 1′ of depth for every 10′ of line. So when trolling, say, 150′ of wire line, your lure will be working around 15′ (deeper if you use a trolling weight).

Fish Tales

To replace an IGFA world record for a fish weighing less than 25 pounds, the replacement weight must be at least 2 ounces more than the existing record. To replace an IGFA record for a fish weighing 25 pounds or more, the replacement weight must be at least 1/2 of 1 percent more than the existing record.

Listen Hear?

You’re not required to have your radio on. But when it is, the law says you must listen to Channel 16 or, for recreational boats, Channel 9.

Wind Fall

Winds coming out of the south or east-tides will be stronger and later than expected. Winds coming out of the north or west-tides will be diminished and earlier than expected.

Foot Speed

At one knot, a boat will travel approximately 1.7′ each second.

Hot Times

To convert from Fahrenheit to Celsius, subtract 32 then multiply by .555. To convert from Celsius to Fahrenheit, multiply by 1.8 then add 32.

What? No 911?

Radio distress signals:

MAYDAY Vessel is threatened by grave and/or imminent danger and requires immediate assistance. PAN-PAN Indicates caller has an urgent message regarding safety of a person or vessel. SECURITÉ (“se-cur-itay”) Indicates caller is about to transmit information concerning safety to navigation or give an important meteorological warning.

A Current Affair Selecting Wire Gauge

Current Length of wire (in feet)
(in amps)
10 or less 15 20 30 40 50
5 14 gauge 12 10 10 8 6
10 10 10 8 6 6 4
15 10 8 6 6 4 2
20 8 6 4 4 2 2
25 6 6 4 2 2 1

Ski-Daddle Hand Signals for Waterskiers

** **Faster: Palm of one hand up Slower: Palm of one hand down Speed okay: Arm up; thumb and forefinger form a circle Right turn: Arm out pointing right Left turn: Arm out pointing left Return to drop-off area: Arm pointing down at a 45-degree angle and swinging Cut motor: Finger drawn across the throat Stop: Hand up, palm forward, like a police officer Skier okay after fall: Hands clenched overhead Pick me up or fallen skier: One ski pointing vertically out of the water ** **

Navy Signal Corps Two-Letter Flag Signals

A C I am abandoning vessel
I T I am on fire
A N I need a doctor
J F I am in distress and need immediate assistance
A Q I have an injured person who needs to be taken off immediately
J G I am aground and in danger
C B I require immediate assistance
J L You are at risk of running aground
C J Do you require assistance?
J W I have sprung a leak
C N I am unable to give assistance
K F I require a tug
C P I am coming to your assistance
K N I cannot take you in tow
D V I am drifting
N C International Distress
D X I am sinking
N E Proceed with great caution
G W Man overboard
N F You are running into danger
I M I request to be escorted until further notice
N G You are in a dangerous position

Hold On! Choosing a Working Anchor

LOA (feet) Danforth Danforth Hi-Tensile Plow Fortress
10 4-S 5-H P-700 G5
15 8-S 5-H P-700 FX7
20 8-S 5-H P-700 FX7
25 13-S 5-H P-1000 FX11
30 13-S 12-H P-1000 FX11
35 22-S 12-H P-1500 FX16
40 22-S 20-H P-1800 FX23
50 40-S 35-H FX37
60 65-S 35-H FX85

Channel Markers VHF Channels

16 Hailing and distress
09 Ship-to-ship and ship-to-coast (when contacting marinas, for example)
68 Same as Channel 9 except it’s also used for commercial ship-to-ship
06 Ship-to-ship communication for safety only
22A If you call the Coast Guard and your situation isn’t life threatening, you’ll be switched to this channel
21A, 83 Coast Guard-to-Coast Guard only
13 Navigational (bridges, locks, and so on)
70 Reserved for digital selective calling
12 Port operations
25, 26, 27, 28 Public telephone-link up with a land-based marine operator
69, 71, 72 Ship-to-ship communication
WX-1, WX-2, WX-3, WX-4 Weather broadcasts

Seven signs that fish are probably nearby

1. A distinct smell like cucumber or cantaloupe often means that fish have been foraging for bait in the vicinity. The smell comes from oils in the chewed-up fish as it floats to the surface.

2. Smooth, thin surface slicks may indicate fish feeding below. The slicks are also caused by fish oils.

3. If birds are working the surface, something is or was there.

4. A sudden eruption of white over a large area says fish are feeding.

5. What appears as a dark stick might in fact be a marlin bill. Dark shapes may be fins. Shadows could be the entire fish.

6. Surface rips where you can see the color of water change or where currents come together churning the surface often cause bait fish to panic. Bigger fish know this and come to eat.

7. Weedlines, driftwood, and buoys are offshore structures that offer small fish protection in open water. If small fish are present, big fish will not be far behind.

Torque About It

To determine the torque of an engine at WOT, use this formula: horsepower x 5.252 __________________ =Torque rpm