The Practical Mariner's Book of Knowledge, 2nd Edition: 460 Sea-Tested Rules of Thumb for Almost Every Boating Situation (INTERNATIONAL MARINE-RMP) - Softcover

Vigor, John

Softcover

ISBN 10: 0071808280 ISBN 13: 9780071808286

Publisher: International Marine/Ragged Mountain Press, 2013

Synopsis

Is this an entertaining book?

The Practical Mariner’s Book of Knowledge is either the most useful boating book ever designed to entertain or the most entertaining book ever designed to be useful. In its alphabetical organization that juxtaposes wildly disparate entries, you can read about the derivation of fi gureheads where you turned to for recommended thicknesses of fiberglass hulls. In betweenthe whimsy, however, is the essence of centuries of seafaring experience distilled into a concise reference for sailors and powerboaters. There may be no substitute for a lifetime of experience, but this book is the next best thing. It should be kept at the navigation station and on every boat.

Inside you will find information that is otherwise scattered through dozens of volumes. If you can't find what you want quickly from the table of contents, there's an exhaustive subject index. If you need more precise data than a rule of thumb can provide, you may very well find it among the 16 appendix tables, which are also indexed.

You'll find rules of thumb for:

• Changing a boat's name
• Towing the safest way
• Burial at sea
• Preventing wood rot
• Hull thickness
• Anchoring rights
• Jib size
• Curing mast vibration
• Time taken for boat tasks
• Survival rations

And a lot more: open it up and get lost in the sage advice and witty wisdom that will make you long for the sea.

"The perfect, practical gift to give or receive." -- The Ensign

". . . reads like a lively conversation with a friendly, seasoned pro." -- Lakeland Boating

About this title

About the Author

John Vigor (Bellingham, WA), a journalist for 35 years and former managing editor of Sea Magazine, has sailed more than 15,000 ocean miles. He is the author of The Practical Mariner’s Book of Knowledge (IM, 1994).

Excerpt. © Reprinted by permission. All rights reserved.

The Practical Mariner's Book of Knowledge

460 Sea-Tested Rules of Thumb for Almost Every Boating Situation

By John Vigor

The McGraw-Hill Companies, Inc.

Copyright © 2013 John Vigor
All rights reserved.

ISBN: 978-0-07-180828-6

Contents

Foreword
Acknowledgments
Introduction
Abandoning Ship
Aground
Air Pressure, on Sails and Rigging
AIS as a Safety Aid
Albatross, Superstition Concerning
Alternators
Anchors and Anchoring
Ballast
Barometers
Batteries
Bearing
Binoculars
Boats
Bulwarks
Buoys
Capsize
Charts
Cleats
Compass
Currents
Decks
Diesels
Dinghies
Dock Lines
Electrical
Engines
Fear
Fiberglass Construction
Fire
Flags
Fog
Fuel
Galleys
Halyards
Horsepower
Hulls
Hurricanes
Keels and Keel Bolts
Knots
Leaks
Lifelines
Lights
Mainsails
Maneuvering
Masts
Miles
Multihulls
Names
Navigation
Oars
Ocean
Outboard Motors
Overhangs
Paint and Painting
Planing
Propellers
Radar
Radio
Rigging
Rope
Rudders
Sail Area
Sail Cloth
Seamanship
Seasickness
Seawater
Singlehanded Boats
Singlehanded Voyagers
Speed
Stability
Tacking
Teak
Tidal Streams
Tides
Varnish
Ventilation
Water
Waves
Wind
Wood
Appendix: Useful Tables and Formulas
Bibliography
Index

Excerpt

CHAPTER 1

A

Abandoning Ship The rule of thumb is never to abandon ship until you have tostep up to your liferaft.

Unfortunately, this is much easier said than done. There is often greatpsychological pressure to escape from the responsibilities, physical labor,decision making, stress, and sense of failure that accompany a sinking situationin heavy weather. Many sailors suffering mental and physical exhaustion after aknock-down or a holing find the thought of drifting off in a rubberliferaft—and thereby abdicating all decision making and physicallabor—immensely appealing. But, all too often, the partially waterloggedyacht is found still floating, months or even years later, while the liferaftand its occupants are never seen again.

Aground See: RUNNING AGROUND, FIRST ACTION TO TAKE

Air Pressure, on Sails and Rigging The force applied by wind to a boat's sails,or to its rigging and superstructure while at anchor, varies with the density ofthe air.

Cold air is denser than is warm air, so a sailboat heels more (with the samesail area and wind speed) in higher latitudes than in the tropics, or more inautumn than in summer.

The force of the wind also increases as a square of its speed, which means thatif the wind speed doubles, its force increases four times.

See also: APPENDIX: HORSEPOWER GENERATED BY SAILS, APPROXIMATE; AND APPENDIX:WIND PRESSURE ACCORDING TO WIND SPEED

AIS as a Safety Aid The automatic identification system (AIS) is a moderndigital, VHF-radio-based transponder system that broadcasts an electronic chartof your area marked with all ships of at least 300 tons gross, plus allpassenger ships. The AIS automatically and continually shows these ships'present positions, speed, compass headings, and much more information.

Yachts and other vessels less than 300 tons are not required to carry full-functionClass A AIS transceivers. Less expensive transceivers that consume lesselectricity and transmit at 2 watts, instead of 20, are available for pleasurevessels. In addition there are receive-only units specially designed for smallcraft. These receive-only units will not alert other ships to your presence butwill provide information to you about their speeds and courses, which, likeradar, could add greatly to your safety at night or in limited visibility,especially in crowded waters. For a free trial run showing vessels in real timein your own area, go to http://marinetraffic.com/ais.

See also: CARD, USES OF; PERSONAL SAFETY, SOME GUIDELINES; entries under RADAR;RESCUE AIDS, ELECTRONIC

Albatross, Superstition Concerning It was widely believed by European marinersthat an albatross housed the soul of a dead sailor.

It was therefore very bad luck to kill one, as Samuel Taylor Coleridge tells usin The Rime of the Ancient Mariner.

Alternator, Power Absorbed by It's easy to regard the alternator as a source offree power, just spinning away as the engine runs. But, in fact, it takes asurprising amount of power—and therefore fuel, which could affect a boat'srange—to turn over an alternator.

The rule of thumb is that the horsepower drain on the engine is twice the numberof kilowatts produced. If, for example, a 100-amp alternator is charging a 12-voltsystem at full capacity, it's producing 1,200 watts or 1.2 kilowatts. So,it steals 2.4 h.p. from the engine's output.

Alternator, Sizing Rule Your alternator should have a recharging capacity inamps of between 25 and 40 percent of the total amp-hours in your battery bank.

This presupposes you are using a modern, multistep regulator that won't allowovercharging, particularly when the batteries become warm. If you don't have amulti-step regulator, the rule of thumb for long battery life is that you shouldlimit the charging rate in amps to 10 percent of available amp-hours. But,because this takes so long, most boaters don't heed this rule, preferring tocharge at about 20 to 25 percent and to buy new batteries more frequently as aconsequence.

Anchor, Best Type to Use Once you understand the idiosyncrasies of yourparticular anchor, you can make it dig in and hold on almost any kind of bottom.However, these are the general characteristics of the more popular types ofanchors:

Pivoting plow type (C.Q.R. and others): Good all-rounder, best in sand and mud.Poor on weed and hard rock. Cannot be fouled by its rode. Good at resettingitself when direction of pull is changed.

Fisherman type (Herreshoff, Luke, and others): Better than most on rocky andgrassy bottoms, but needs to be heavier than most other anchors and can befouled and dislodged by its own rode. Small fluke area drags easily through softbottoms. Awkward to handle, but can be dismantled for stowage.

Lightweight type (Danforth, Fortress, Performance, and others): Sharp points onflukes are good at digging into hard sand and better than most at penetratinggrass. Large fluke area is helpful in soft mud. Not good at resetting itself.Has great holding power.

Bruce type: Very strongly built, good all-rounder. A modified plow with nomoving parts. Cannot foul itself. Stows conveniently in a bow roller and resetsitself well. Good in sand, mud, rock, and coral.

Delta type: A sturdy, one-piece, non-pivoting plow. Weighted to land correctly,penetrate hard bottoms, and set itself quickly. Launches itself easily from bowroller and cannot foul its rode.

New types: Experimenting with new types of anchors never seems to cease. Of therecent new anchors, some of the most common are the Manson and the Rocna fromNew Zealand, the French Spade, and the Bulwagga from Florida. Some of them, suchas the Manson and Rocna, have large roll bars to keep the anchor right-way up onthe bottom, and their manufacturers claim advantages over conventional designs.But until these anchors have demonstrated their effectiveness over a long periodof time, such claims are difficult to prove. No one anchor design has ever beenthe best for all bottom conditions. For many years, longdistance cruisers havefavored proven designs such as the C.Q.R., Bruce (the genuine one), Danforth,and Delta, simply because they behave reasonably well most of the time.

Anchor, Direct Strain on Thomas Fleming Day, editor of The Rudder, declared in1901: "The direct strain on anchors is of no consequence except in very highwinds; it is the sea that causes them to leave their hold." He likened theanchor (an old-fashioned fisherman anchor, of course) to a workman's pick buriedto the hilt in the earth. "When given sufficient scope, the anchor, like thepick, is resisting a pull at right angles, and stands fast, but the minute thesea begins to move the vessel up and down the handle of the anchor is worked upand down; the shorter the scope the more surely is this motion transmitted, andthe more effective it is in breaking out the arm."

Anchor, Fisherman, Ideal Proportions of The fisherman-type anchor is not widelycarried on modern pleasure boats because it's awkward to handle and stow, andbecause it's easily fouled by its own rode. Newer designs of anchor—suchas the Bruce, the C.Q.R., the Danforth, the Delta, and others—have largelyeliminated these faults, but the fisherman still has its uses, especially wherethe bottom is hard, rocky, or covered with grass.

Not all fisherman anchors are created equal, however. Claud Worth, the classicBritish sailor and author of Yacht Cruising, gave this advice for selection:

The arms and shank should be oval or flat in section. The flukes should be sharpand long to bite into hard ground. They should make an angle of about 40 degreeswith the shank. The measurement from the crown to the hole for the stock shouldbe not less than 11/2 times, nor more than 1 times, the length of thechord—the chord being the distance between the tips of the two flukes. Thestock should be the same length as the shank.

Anchor, Proper Scope Under favorable weather conditions, the minimum scope of ananchor cable should be 5:1. Under average conditions, a scope of 7:1 isconsidered satisfactory. As much as 10:1 is needed in heavy weather.

Scope is measured as the ratio between the depth of the water and the length ofthe anchor cable veered out. Note that the depth of the water in thiscalculation also includes the extra length between water level and the bowchock. In other words, depth of water really means the distance from your bowroller straight down to the sea bed.

These amounts of scope allow a nylon rode with at least 8 feet of chain(preferably more) attached to the anchor to exert a low angle of pull againstthe anchor. Most anchors tend to break out if the angle of pull is more than 8degrees from the horizontal.

The temptation to pay out less scope on an all-chain rode should be resisted.Although the catenary of the chain cushions shock loads from large waves, oncethe slack has been taken up, the snatching loads on your anchor and Samson post,or anchor winch, are much greater than they would be with a stretchy nylon rode.

Anchor, Safe Minimum Weight of Although it's their engineering design that makesthem effective, anchors still need weight to dig into the bottom. It's generallyagreed that no matter how small a yacht may be, it's not wise to use any anchorweighing less than 30 pounds for any purpose other than temporary halts duringwhich the yacht is adequately manned and ready to sail at short notice.

A useful rule of thumb for plow anchors used on sailboats engaged in longcruises is to have 1 pound of anchor for every 1 foot of boat length, measuredon deck. This ensures that the anchor will have sufficient weight to penetratemost "difficult" bottoms such as those of hard sand or those covered with weedor grass. Some modern lightweight anchors, while certainly possessing adequateholding power when properly dug in, may not be able to penetrate such bottoms.

See also: APPENDIX: ANCHORS, RECOMMENDED SIZES

Anchor, Size of Owners of cruising yachts should beware of generalizedsuggestions from anchor manufacturers about the size of anchors they need.

Seventy percent or more of many types of anchors are sold to inland fishermenfor use with small open boats on lakes. Understandably, manufacturers'recommendations are tailored to this market, not the market constituting the 2percent of their customers with offshore voyaging boats.

See also: APPENDIX: ANCHORS, RECOMMENDED SIZES

Anchor, Time Spent at, While Cruising While cruising in Mexico, the Caribbean,and the South Pacific, the average yacht spends 10 percent of the time at sea, 5percent tied to docks, and 85 percent at anchor.

This rule of thumb, which originated with Lin and Larry Pardey, points to theimportance of good ground tackle and an efficient dinghy.

Anchor, Weight One Person Can Handle The rule of thumb is that it's possible fora person of average strength and fitness to raise and bring aboard a 60-poundDanforth or C.Q.R. anchor without any special gear.

Nevertheless, it's heavy work, and in boats exceeding 5 or 6 tons ofdisplacement, some mechanical assistance is generally considered necessary. Achain pawl attached at or near the bow roller is of great assistance. It alsomakes it feasible to do away with an anchor winch or windlass altogether whenusing a 35-pound anchor and 51/6 chain, particularly if an auxiliary engine can beused to ease the ship to windward while weighing.

Anchorage, Safe When seeking a safe anchorage, bear in mind these basicrequirements:

• Shelter from wind and waves

• Room to swing around the anchor

• Sufficient depth of water at low tide

• Good holding ground for the anchor

Anchor Chain, Bitter End, Securing The inboard or bitter end of the anchor chainshould be secured with about 3 fathoms of appropriately sized nylon line to thebase of the Samson post, king post, or other heavy structural member in thechain locker.

The nylon line is easier to cast off, or cut and buoy, in the event of the cablehaving to be slipped quickly. The elasticity of the nylon also helps absorb theconsiderable shock of a runaway anchor chain coming up short against its bitter-endfastening. A chain shackled internally to a bolt through the bow mightsimply blast a hole through the hull when it reaches the end of its tether.

See also: CHAIN, STRENGTH OF

Anchor Chain, High-Tensile High-tensile chain is traditionally not recommendedfor anchor rodes. Although it has a high breaking load, it can fail withoutwarning. Ordinary galvanized steel chain with short oval links is usuallyspecified for pleasure-boat use because it gives visible signs of stretchingbefore breaking.

Anchor Chain, Markings for If you have no other way to judge how much chainyou're veering, paint a white mark at least a foot long on the cable every 5fathoms (30 feet). All too often, in the absence of some method of measuring,insufficient scope is given, which is the gravest crime in the anchoring laws.

If you have trouble counting the marks as the line is paid out, you could try asystem with fewer markings in different colors. That way, you can check at aglance the amount of cable veered.

Anchor Chain, Size of The American Boat and Yacht Council uses windage on theboat as a criterion for selecting chain. It recommends that the chain have abreaking strength to withstand at least five times the normal horizontal load.

To estimate the horizontal load, you need to know the frontal surface area onyour boat exposed to the effect of windage. The rule of thumb is to multiply bowheight by maximum beam. The result is in square feet. Add two-thirds of thatfigure to account for spars, rigging, and deck gear. Add the frontal area, insquare feet, of anything else, such as a raised dodger. Then double theresulting figure to account for the effects of yawing. The pressure of wind onthis square footage varies with its speed.

See also: CHAIN, STRENGTH OF; APPENDIX: CHAIN, RECOMMENDED SIZES FOR ANCHOR; ANDAPPENDIX: WIND PRESSURE ACCORDING TO WIND SPEED

Anchor Light, Required Size Vessels under 50 meters in length must show an all-roundwhite light that is visible for 2 miles when anchored between dusk anddawn, except in designated "special anchorages."

The 2-mile range is normally reached by a 12-watt electric bulb or a half-inchwick in a kerosene lantern showing through clear glass.

See also: NAVIGATION LIGHTS, SPECIFICATIONS FOR

Anchor Rode, Minimum Length of The length of anchor rode that a vessel needsobviously depends on the depth of water in which she wants to anchor. However,unless she is too small to stow it, no boat should carry less than 30 fathoms(180 feet) of anchor rode. This is sufficient to keep her safe, in all butexceptional weather, in 25 feet of water.

However, it's vastly preferable in all cases to carry at least 50 fathoms (300feet) to allow for anchoring in deeper water.

Incidentally, the term rode is generally taken to mean all the gear lyingbetween a boat and her anchor—no matter whether it's rope orchain—although in New England and Eastern Canada it refers to a fishingboat's anchor rope.

Anchor Scope, Effect of It often happens that crowded anchorages limit yourswinging room and, therefore, your scope. The more horizontal the rode on thesea bottom where it attaches to the anchor, the better. But if you are forced tolie to a shortened rode, here is how it will affect your anchor's holding power.Presuming that a scope of 10 to 1 offers 100 percent holding power, then,roughly speaking:

7 to 1 = 90 percent

6 to 1 = 85 percent

5 to 1 = 75 percent

4 to 1 = 65 percent

3 to 1 = 50 percent

2 to 1 = 35 percent or less (maybe much less)

Anchoring, Problems with Coral Heads When anchored in areas where coral headsare prevalent, a chain rode frequently wraps around one or more heads,dangerously shortening the scope. The general rule is to buoy the chain so thatthe main part of the rode cannot foul coral. Usually, several buoys are needed.

Some experienced cruisers prefer to anchor in depths of between 90 and 120 feetwhen possible, because coral heads are far less common in deeper water. But thisrequires more anchor line than many small cruisers can comfortably carry.

Anchoring, Problems with Snatching In shallow water and steep waves, any boatcan snatch badly at her anchor rode. In such circumstances, it's easier on thegear to use a nylon anchor rode to absorb the snatching loads. Even with an all-chainrode, a 20-foot spring of three-strand nylon made fast with a rollinghitch to the chain near the bow is probably more effective than is a travelerweight in preventing destructive snubbing.

(Continues...)

Excerpted from The Practical Mariner's Book of Knowledge by John Vigor. Copyright © 2013 by John Vigor. Excerpted by permission of The McGraw-Hill Companies, Inc..
All rights reserved. No part of this excerpt may be reproduced or reprinted without permission in writing from the publisher.
Excerpts are provided by Dial-A-Book Inc. solely for the personal use of visitors to this web site.

Edition details

• Publisher: International Marine/Ragged Mountain Press
• Publication date: 2013
• Language: English
• ISBN 10: 0071808280
• ISBN 13: 9780071808286
• Binding: Paperback
• Edition number: 2
• Number of pages: 288