Fuel Prices Are Just One Thing To Worry About

The boat/yacht depicted on the right may not be your current “on the water ride” but fuel prices are affecting every boater to some extent. In some locations at well over $5 a gallon for regular marina gas, boat fuel costs much more than gas used to fuel cars. What makes boat fuel so expensive? The cost of boat fuel is increased due to an additive that prevents bacterial growth, and because the marinas sell such a  low volume compared to regular filling stations for cars. But is “shock at the pump” the only thing a boater should be worried about?

Clean Boating – How to do Your Part

Petroleum in or on the water is harmful and, in some cases, fatal to aquatic life. Benzene, a carcinogen, is in gasoline. Oil contains zinc, sulfur, and phosphorous.

Once petroleum is introduced into the water, it may float at the surface, evaporate into the air, become suspended in the water column or settle to the sea floor. Floating petroleum is particularly noxious because it reduces light penetration and the exchange of oxygen at the water’s surface. Floating oil also contaminates the microlayer. The microlayer refers to the uppermost portion of the water column. It is home to thousands of species of plants, animals, and microbes. The abundance of life in the microlayer attracts predators: seabirds from above and fish from below. Pollution in the microlayer, thus, has the potential to poison much of the aquatic food web.

Also worth noting, a single pint of oil released onto the water can cover one acre of water surface area.

The Law

Because of the harm associated with petroleum, the discharge of oil is absolutely prohibited. The Federal Water Pollution Control Act prohibits the discharge of oil or oily waste into or upon the navigable waters of the United States or the waters of the contiguous zone if such discharge causes a film or sheen upon, or discoloration of, the surface of the water, or causes a sludge or emulsion beneath the surface of the water. Violators are subject to a penalty of $5,000 to $10,000.

The United States Coast Guard must be notified anytime a spill produces a sheen on the water. Call the National Response Center at 1-800-424-8802. Report the location, source, size, color, substance, and time of the spill. Failure to report a spill may result in additional fines.

The Clean Water Act (33 CFR 153.305) also prohibits the use of soaps or other dispersing agents to dissipate oil on the water or in the bilge without the permission of the Coast Guard. Soaps, emulsifiers and dispersants cause the petroleum to sink in the water column and mix with sediments where they will remain for years. Also, the soaps themselves are pollutants. You may be fined up to $25,000 per incident for the unauthorized use of soap or other dispersing agents on the water or in the bilge. 

Fueling Practices

Gas or diesel may be spilled during the act of fueling: as backsplash out the fuel intake or as overflow out the vent fitting. Spills of this sort harm aquatic life, waste money, and can result in stains on the hull and damage to the gel coat and striping. Follow these tips to avoid problems:

• Fill tanks to no more than 90 percent capacity–gas that is drawn from cool storage tanks will expand as it warms up onboard your vessel.
• To determine when the tank is 90 percent full, listen to the filler pipe, use a sounding stick (if possible), and be aware of your tank’s volume.
• Rather than filling your tank upon your return to port, wait and fill it just before leaving on your next trip. This practice will reduce spills due to thermal expansion because the fuel will be used before it has a chance to warm up.
• Fill portable tanks ashore where spills are less likely to occur and easier to clean up.
• Use oil absorbent pads to catch all drips.
• Slow down at the beginning and end of fueling.

Bilge Maintenance and Oil Changes

Engine oil tends to accumulate in bilges. If no precautions are taken, the oil is pumped overboard along with the bilge water. Discharging oily water is illegal. To avoid fines and to protect water quality, follow these tips:

• Keep your engine well tuned to minimize the amount of oil that is released. Be sure there are no leaking seals, gaskets or hoses.
• If you change your own oil, purchase a non-spill pump to draw crankcase oils out through the dipstick tube and slip a plastic bag over used oil filters prior to their removal to capture any drips. Hot drain the filter by punching a hole in the dome end and draining for 24 hours. Recycle the collected oil. Recycle the metal canister if practical. If not, dispose in your regular trash.
• Place oil absorbent materials or a bioremediating bilge boom in the bilge.
• Place an oil absorbent pad under the engine.
• Replace oil absorbent materials regularly.
• Look for contractors or marinas that offer a bilge pumpout service.
• Do not treat oily water with detergents. Soaps pollute and make clean up impossible. You may be fined up to $25,000 for using soaps to dissipate oil.

Disposal of Oil Absorbent Materials

The disposal of used oil absorbent material depends on what type of product it is and how it was used:

• Standard absorbents that are saturated with gasoline may be air dried and reused.
• Standard absorbents saturated with oil or diesel may be wrung out over oil recycling bins (if they are saturated with oil or diesel only!) and reused. Alternatively, they should be double bagged with one plastic bag sealed inside of another and tossed in your regular trash.
• Bioremediating bilge booms may be disposed in your regular trash as long as they are not dripping any liquid. Because the microbes need oxygen to function, do not seal them in plastic bags.

Emissions Control

Marine engines–especially 2-stroke outboard motors–produce the highest average level of hydrocarbon exhaust emissions after lawn and garden equipment. Hydrocarbon emissions contribute to ground level ozone, a known health risk. Follow these tips to help your engine operate as efficiently as possible:

• Use the gas to oil ratio recommended by the engine manufacturer. Too much oil can foul spark plugs and too little can lead to increased engine wear or even failure.
• Use premium two-cycle engine oil (TC-W3 or TC-W4). Premium oils improve engine performance and reduce pollution because they burn cleaner, contain more detergents, and prevent formation of carbon deposits.
• Use gasoline with the octane level recommended by the engine manufacturer.

Preventative Equipment

Products are available commercially which can help you prevent spills and reduce emissions:

• Install a fuel/air separator along your vent line. These devices allow air, but not fuel to escape through a vent opening.
• Attach a safety nozzle to portable gas cans used to fill outboard engines. These nozzles automatically stop the flow of fuel when the receiving tank is full.
• To prevent oily bilge water from being discharged, install a bilge pump switch that leaves an inch or two of water in the bilge. Alternatively, connect a bilge water filter to your vessel’s bilge pump. Filters will remove oil, fuel and other petroleum hydrocarbons from the water.
• When it is time to buy a new engine, select a fuel efficient, low emission model.
• Attach a container to the external vent fitting to collect overflow. There are products on the market that may be attached to the hull with suction cups. A rubber seal on the container fits over the fuel vent allowing the overflow to enter the container. Fuel captured in this manner can be added to the next boat to fuel.

In Case of a Spill

• Stop the flow.
• Contain the spill.
• Call the U.S. Coast Guard National Response Center at (800) 424-8802.

Ways to Save on the Water this Summer

With the ever spiraling cost of fuel for your boat, here are a few tips on how you can save. I know, the news has been reporting that prices should be going down but as was noted by Jay Leno recently, “The price of oil is now under $100 a barrel. The oil companies say they should be passing on the savings to us in six or seven years.”

Tips For Reducing Fuel Usage:

• Slower speeds on the water will reduce use.
• The proper use of trim tabs reduces drag, especially while accelerating up to planning speeds.
• Minimize the amount of time that you idle at the dock.
• Minimize the use of onboard generators.
• Use dock-side electrical power in lieu of generators.
• Have a float plan so you know exactly where you’re going.
• Make sure the hull is clean.
• Don’t under-power your boat. It’s important you have enough motor to handle the load.
• Check your propeller. If your boat is slow “out of the hole” (getting up on plane) or lacks top-end speed, you might have the wrong propeller.
• A well-tuned engine uses less fuel.
• Use the grade of gasoline specified by the engine manufacturer.

Boat Ownership – Keeping It Yours

Over the past several days, there were many news articles related to boating thefts across the country.

Perhaps the reason could be desperate people in a struggling economy, the availability of  unlocked boats or simply a long stretch of nasty weather.  Thieves make assumptions about your habits and conclude that you won’t be going anywhere near your boat while the weather is bad.

Across the nation, more and more boats, trailers, equipment, electronics and personal items are stolen each year. Most of these crimes are committed by amateurs who, when tempted with an easy opportunity, can’t resist that temptation. Remember the old adage that locks are just a means of keeping honest people honest. This certainly applies to boating.

You would be surprised at how often, when strolling the fuel dock, you will find a boat that has pulled up for fuel, or ice or refreshments, just sitting there unattended with the keys in the ignition or, worse yet, idling away. Or even if the keys aren’t present you might see a handheld VHF radio or a pair of expensive binoculars just lying in the seat or on the dash.

What can you do to make sure that your boat stays in your possession? Read on for tips on security.

MARK IT:

Permanently mark or engrave your boat, your trailer, all your equipment, electronics and personal items which you use regularly on your boat with your vessels hull identification number (HIN) and/or your driver’s license number. Your boat of course, unless manufactured prior to 1972, will already have a HIN on the transom. Permanently mark your driver’s license number in a location that is not readily accessible or noticeable. The same should apply to the trailer. Mark your boat’s HIN and your DL number on the underside of the tongue or axle. As for your equipment, electronics and other items, use some method of permanently marking them as well.

Be sure to keep a copy of your boat and trailer registrations at home in a safe place. It is also a good idea to take a hull rubbing of your HIN. Take a sheet of thin paper and tape it over your HIN number on the transom. Using a soft leaded pencil, rub back and forth across the number lightly until in shows up on the piece of paper.

RECORD IT:

Make a complete inventory of your boat, trailer and equipment. List all electronic gear, binoculars, outboard motors, PFDs, fishing equipment etc. by brand, model, and serial numbers if available. Also record your boat by make, model, registration and HIN number. Be sure to record the license number of your trailer.

Keep this master inventory list at home and keep a copy for reference in a hidden place on your boat in case you find something missing.

PHOTOGRAPH OR FILM IT:

Take pictures or videotape your boat, trailer and equipment from all angles. Keep copies at home in a safe place. Perhaps alongside your insurance papers.

ARM IT:

For larger boats, consider an alarm system. Self-contained systems are inexpensive and can be purchased at most any radio shack, electronics or marine store. Be sure to choose a system specifically designed for boating use. The damp and constantly moving marine environment puts demands on the alarm system requiring special sensors and properly protected location. Systems not designed for marine use may malfunction or report false alarms. Be sure, if you have an enclosed cabin, to include a smoke detector and carbon monoxide (CO) detector in your alarm system.

SECURE IT:

Boats should be covered and secured as completely as possible. Ignition switches should be locked and additional steps such as installing a hidden “kill switch,” hidden fuel shut off. I once met a man who even lugged his starter battery back and forth from his home to his boat.

Boats on trailers are easy crime targets if thieves can just hitch up and drive away. Here are several ways that you can help prevent that:

• If possible, store the boat and trailer in a locked garage, secured boat storage facility or mini-storage warehouse.
• Keep the boat well inside your yard, preferably out of sight.
• If possible, turn the trailer around so the it is “nose” in rather than out.
• In a carport or driveway, park a vehicle in front of the trailer, blocking easy removal.
• For any type of outside storage, remove at least one wheel from the trailer. Be sure to block up the axle to keep the trailer level.
• Use a high-security chain and quality lock to secure the boat and trailer to a fixed object such as a tree or post.
• No matter how you store your trailer, get a trailer hitch lock.
• Some trailers are available that allow you to remove the forward part of the tongue which contains the hitch.

STORE IT:

Obviously your best bet is to remove all equipment from your boat and store it in the garage or other secure area. Make sure you lock hatches and opening ports. If your boat doesn’t have them, or they are broken, you can purchase hatch locks at any marine store. When possible, valuable and easily removed items should be secured below deck in a locked compartment. Lockers should be equipped with non-removable hasps and hinges and secured with padlocks. Lock outboard motors and fuel tanks to the boat. When your boat is left unattended, close the window curtains if you have them so people can not “window shop.”

If your boat is kept in the water at a dock, consider chaining it to the dock. Also, get to know your marina neighbors and form a marina watch group.

INSURE IT:

Insurance is an important part of any theft protection plan. Unfortunately, it’s sometimes seen as a substitute for security precautions. True, insurance may replace stolen property and repair damage but there is usually a deductible that must be met and there are intangibles that insurance doesn’t cover. Down time, inconvenience and aggravation normally aren’t compensated.

Finally, insurance companies don’t like losses. Just one claim can result in increased rates and a loss history will probably result in cancellation. Even when no claims have been filed, using a facility with a poor crime history can result in prohibitively high premiums or denial of coverage.

REPORT IT:

What should you do if you are a victim of marine theft? Immediately report your loss to your local law enforcement agency, the United States Coast Guard if on federal waters, your insurance company and the marina or storage facility manager. When a loss occurs, the ability to positively identify property is crucial to its recovery and the the prosecution of thieves and dealers in stolen goods.

By following the above suggestions you can reduce the risk of loss of your boat, trailer or equipment by theft. You should also exercise caution when buying a boat or running across a “good deal” on equipment. To avoid problems, match the HIN listed on the title and registration to the one on the boat. Inspect the HIN on the transom to be sure it has not been altered in any way. (Also, contact the manufacturer to see if a second, duplicate HIN was placed on the vessel or equipment in an inconspicuous place.) And, if you think that pair of $500.00 binoculars is a real bargain at only twenty five bucks…well remember that saying, if it is too good to be true…

Recreational Boating Statistics 2012

In 2012, the Coast Guard counted 4515 accidents that involved 651 deaths, 3000 injuries and approximately $38 million dollars of damage to property as a result of recreational boating accidents.

The fatality rate was  5.4 deaths per 100,000 registered recreational vessels. This rate represents a 12.9% decrease from last year’s fatality rate of 6 deaths per 100,000 registered recreational vessels.

Compared to 2011, the number of accidents decreased 1.6%, the number of deaths decreased 14.1% and the number of injuries decreased 2.6%.

Almost seventy-one (71) percent of all fatal boating accident victims drowned, and of those, almost eighty-five (85) percent were not reported as wearing a life jacket.

Almost fourteen percent (14) of deaths occurred on boats where the operator had received boating safety instruction. Only nine (9) percent of deaths occurred on vessels where the operator had received boating safety instruction from a NASBLAapproved course provider.

Seven out of every ten boaters who drowned were using vessels less than 21 feet in length.

Operator inattention, operator inexperience, improper lookout, machinery failure, and excessive speed rank as the top five primary contributing factors in accidents.

Alcohol use is the leading contributing factor in fatal boating accidents; it was listed as the leading factor in 17% of deaths.

Twenty-four children under age thirteen lost their lives while boating in 2012. Ten children or approximately forty-two (42) percent of the children who died in 2012 died from drowning. Two children or twenty (20) percent of those who drowned were wearing a life jacket as required by state and federal law.

The most common types of vessels involved in reported accidents were open motorboats (47%), personal watercraft (19%), and cabin motorboats (15%).

The 12,101,936 recreational vessels registered by the states in 2012 represent a 0.59% decrease from last year when 12,173,935 recreational vessels were registered.

For the full report click here.

Introduction to Navigation Part 7 Estimating Time of Arrival

This will be the end of our  7 part series on “Introduction to Navigation.” We hope that we have given a brief overview of what you would be learning in the Nautical Know How Coastal Navigation Course. Trust me there is much, much more that we did not touch on.

Learning the “Art of Navigation” is not difficult but there are several steps that must be learned along the way. After learning about latitude and longitude, distance, direction and reading a nautical chart, you will start putting these processes together to solve real-time problems. On piece of practical information you might want to use is estimating time of arrival.

These basics are covered in the online Nautical Know How Basic Boating Safety Course at
http://boatsafe.com/navigation
 .

Assume that you will leave your marina or boat ramp on a trip to a nearby restaurant for lunch.

• You have made reservations at the restaurant for 1200.
• The restaurant is 29 nautical miles from your marina.
• You plan on a leisurely cruise at a speed of 12 kts.

What time must you leave your marina to arrive at the restaurant at your reservation time?

This is a simple Distance, Time, Speed question. The formulas to use for the calculations are made simple if you remember, and actually write in a corner of your chart, the following diagram.

The “D” represents distance, “S” represents speed and “T” represents time. In order to solve a distance, speed, time problem you need two of the three values and then must solve for the third.

Using the diagram, cover the unknown value with your finger and what you have left is the formula to solve the problem.

In our problem we know the distance and the speed so we cover up the “T” and the resulting formula is “D” over “S” or “D” divided by “S”.

Using this formula, the first step is to calculate how long it will take you to get to the restaurant by cruising at 12 knots for 29 nautical miles.

29 / 12 = 2.42 hours

Note: This is not two hours and 42 minutes, it is 2 hours and 42 hundredths of an hour. We now have to convert this decimal to minutes by multiplying .42 X 60.

.42 X 60 = 25 minutes – So…our trip will take 2 hours and 25 minutes.

Now that we know how long the trip will take, we simply need to subtract that time from the time of our 1200 reservation.

1200 – 225 = 0935

1160 – 225 = 0935

Note: that in order to subtract we had to borrow an hour from the hours column. 1160 is the same as 1200. We must leave the marina or boat ramp at 0935 (9:35 am) in order to arrive at the restaurant by noon.

If you would like to learn more about Time, Distance, Speed calculations or other aspects of navigation, check out our Nautical Know How Coastal Navigation Course.

Related Posts:

http://boatsafe.wordpress.com/2011/05/12/introduction-to-navigation/

http://boatsafe.wordpress.com/2011/05/13/introduction-to-navigation-part-2-nautical-charts/

http://boatsafe.wordpress.com/2011/05/16/introduction-to-navigation-part-3-definitions/

http://boatsafe.wordpress.com/2011/05/17/introduction-to-navigation-part-4-getting-to-know-your-magnetic-compass/

http://boatsafe.wordpress.com/2011/05/18/introduction-to-navigation-part-5-understanding-latitude-and-longitude/

http://boatsafe.wordpress.com/2011/05/19/introduction-to-navigation-part-6-time-calculations/

Introduction to Navigation Part 6 Time Calculations

Navigation uses the 24-hour clock as its standard.  If you were fortunate enough to have been in the military, you probably are familiar with the 24-hour clock or military time.  However, if it has been a while since you have done anything except look at the numbers on your digital wristwatch you may need to brush up.  All time used in navigation is expressed as four digits.  The first two digits are the hour number.  The second two numbers are the minutes. Starting with 0000 hours at midnight, the hours are counted as 0100, 0200, 0300, etc. through 1200 at noon.  After the noon hour the hourly intervals continue to count with 1300 (1:00 PM), 1400 (2:00 PM), etc. until you reach midnight (0000) again.

Minutes are indicated with a two-digit number after the hour interval.  For example, 8:30 AM is written as 0830, and 12 minutes past four o’clock in the afternoon would be written as 1612.  Using military time there is no need to use AM or PM.  A time of 0900 is nine hours after midnight (9:00 AM), and 9:00 PM would be written as 2100 (9 hours past 1200).

These basics are covered in the online Nautical Know How Basic Boating Safety Course at
http://boatsafe.com/navigation
 . It is highly recommended that, prior to beginning this advanced Coastal Navigation Course, each student successfully complete the Basic Boating Safety Course.

Calculating Time

The 24 hour clock makes it easy when you have to add or subtract time, one of the essential parts of doing distance, speed, time calculations.  Obviously, if you need to know how far you have gone at a certain speed you need to know how long (in time) you have been traveling.

As an example, if you wanted to find the time interval between a departure time of 0915 and an arrival time of 1325, you could set up a simple subtraction problem.	Hr    13  -09   4 Hr	Min 25 15 10 Min
Some problems can become a little more complex than the straight-forward subtraction problem above. What if you needed to find the time interval between your departure of 1345 and your arrival at 1515? When you set up the problem you get an unusual looking situation.	Hr    15   -13     ?	Min 15 45 ? Min
You should remember that the two sets of two digit numbers represent two different units, i.e. hours and minutes. Just like in regular math, you must subtract the units to the right before you can subtract the units to the left.  In this case you have to borrow an hour from the hours unit.  Converting the hour to minutes, you have borrowed 60 minutes. So, 1515 is rewritten as 1475.	Hr    15    14   -13    1 Hr	Min 15 75 45 30 Min

Once you have properly set up the problem by borrowing an hour and converting to minutes, you simply perform a standard subtraction by taking 45 minutes from 75 minutes and 13 hours from 14 hours.  You time underway equals 1 hour and 30 minutes.

Related Posts:

http://boatsafe.wordpress.com/2011/05/12/introduction-to-navigation/

http://boatsafe.wordpress.com/2011/05/13/introduction-to-navigation-part-2-nautical-charts/

http://boatsafe.wordpress.com/2011/05/16/introduction-to-navigation-part-3-definitions/

http://boatsafe.wordpress.com/2011/05/17/introduction-to-navigation-part-4-getting-to-know-your-magnetic-compass/

http://boatsafe.wordpress.com/2011/05/18/introduction-to-navigation-part-5-understanding-latitude-and-longitude/

USCG: Recreational Boaters Can Avoid Accidents

National Safe Boating Week Highlights
Education and Life Jacket Wear

While recreational boating accidents were down overall in 2012, operator-controllable factors, including alcohol use, excessive speed, improper lookout, and failure to follow navigation rules, remain among the top causes of injuries and fatalities on the water. The U.S. Coast Guard supports National Safe Boating Week, May 18-24, as an opportunity to remind all boaters of simple things they can do to boat safely.

The Memorial Day holiday, with warmer weather and a three-day weekend, brings crowded waterways, with many new or inexperienced boaters. And, while 63.4% of boaters consider themselves “very experienced,” only 42.6% have ever taken a boating safety course.*

Understanding the navigational rules of the road and boating defensively are always vital, but particularly so during peak boating periods. Wearing a life jacket, avoiding alcohol, taking a boating safety course, and getting a free vessel safety check are fundamentals that every boater should implement.

“National Safe Boating Week is the perfect time for new and experienced boaters alike to put some extra focus on safety,” noted Jeff Hoedt, Division Chief, Boating Safety Division, U.S. Coast Guard. “Every 2.5 hours someone is injured or killed in a recreational boating accident in the U.S., and all too often these accidents result from failing to take a few simple precautions.”

Coast Guard statistics indicate that the chances of drowning in a recreational boating accident are 1 in 66 for a boater wearing a life jacket, but almost 1 in 11 for a boater who is not.**

“With the launch of the summer boating season in much of the country, we are joining with the National Safe Boating Council and many other valued partners to remind boaters to enjoy the water responsibly and safely,” adds Hoedt.

The Coast Guard’s Boating Safety Resource Center provides recreational boaters information and resources under the “Safety” tab at
http://www.uscgboating.org
.

* Source: U.S. Coast Guard 2011 National Recreational Boating Survey
** Source: U.S. Coast Guard 2012 Recreational Boating Statistics

Introduction to Navigation Part 5 Understanding Latitude and Longitude

Finding a street address on earth is not a difficult task, however finding a specific location in the middle of the ocean can present the mariner with a few problems.  In order to locate a specific location anywhere on earth, a grid system has been developed to give each area on the earth a specific address.  This system deals with “parallels of latitude” and “meridians of longitude.”

In order to begin to understand how to navigate, the navigator must understand some basic terminology and how it relates to the grid system.

These basics are covered in the online Nautical Know How Basic Boating Safety Course at
http://boatsafe.com/navigation
 . It is highly recommended that, prior to beginning this advanced Coastal Navigation Course, each student successfully complete the Basic Boating Safety Course.

 A “great circle” is a circle formed on a sphere, such as the earth, by the intersection of a plane passing through the center of the sphere.  An arc of a great circle is the shortest distance between two points, hence a great circle route is the shortest route between two points on the earth.  You might think of splitting an orange down the middle and going through the center.  The plane exposed would represent a great circle.

 A “small circle” is a circle formed on a sphere, such as the earth, where the intersection of a plane does not pass through the center of the sphere.  Cut that same orange in any other manner that does not pass through the center and you have created a small circle.

Parallels of Latitude are small circles that are measured from the equator (the only latitude that is a great circle) beginning at O° latitude at the equator to 90° North and South at the Poles.  These parallels are equal distance apart and run horizontally across a chart, like the rungs on a ladder.  You can use the “ladder” analogy to remember that “laddertude” lines are drawn across the chart, not up and down. 

Because latitude lines are equal distance apart they can be used to measure distance on the surface of the earth.  The only parallel of latitude that is a “great circle” is the equator itself as shown in the graphic. You will find latitude measurements on the side of your nautical chart.

Meridians of Longitude are “great circles” that pass through the north and south geographic poles.  The meridian of longitude that cuts through the earth at Greenwich, England is labeled as O° longitude and is known as the prime meridian.  Longitude is then measured from O° at Greenwich to 180° West and 180° East of Greenwich. The 180°th of longitude is the International Dateline.

Related Posts:

http://boatsafe.wordpress.com/2011/05/17/introduction-to-navigation-part-4-getting-to-know-your-magnetic-compass/

http://boatsafe.wordpress.com/2011/05/16/introduction-to-navigation-part-3-definitions/

http://boatsafe.wordpress.com/2011/05/13/introduction-to-navigation-part-2-nautical-charts/

http://boatsafe.wordpress.com/2011/05/12/introduction-to-navigation/

Introduction to Navigation Part 4 Getting to Know Your Magnetic Compass

You may have noticed, if you have looked at a nautical chart, that there were two rings on the compass rose. The outside ring is based on true north and the 000° direction points to the true North Pole. On the inside ring labeled “MAGNETIC” the  000° direction points in a different direction than the outside ring.

These basics are covered in the online Nautical Know How Basic Boating Safety Course at
http://boatsafe.com/navigation
 .

The difference between True and Magnetic is called “Variation.” Variation is a naturally occurring disturbance caused by the magnetic north pole. Variation will change depending on where you are located on the earth. If you are operating on the West Coast of the US you will have east variation because the magnetic north pole is located east of you. On the East Coast of the US you have west variation because the magnetic north pole is west of your location.

Another error which may show up in your magnetic compass is called “Deviation.”  Magnetic compasses are also affected by magnetic fields on the vessel itself. Just put some sort of ferrous metal such as a screw driver next to your compass and you will see an example of this error.

Significant errors of deviation could be caused by metal tanks, your engine, metallic objects near your compass or even electromagnetic interference caused by your radio.

To safely and accurately navigate from one position to another it is important to be able to correct for both “variation” and “deviation”  and be able to steer a course by your magnetic compass.

If you want to learn more about the magnetic compass and how to calculate TVMDC…READ MORE.

Introduction to Navigation Part 3 Definitions

The following navigation terms are used in most recognized navigational texts. Learning and understanding what they mean will give you a head start on the information that is to be presented in later chapters. Don’t worry about memorizing all these at this time. You will get plenty of exposure to these terms as you advance through the course.

These basics are covered in the online Nautical Know How Coastal Navigation  Course at
http://boatsafe.com/navigation
 .

Piloting is defined as the determination of the position and the direction of the movements of a vessel. This involves frequent or continuous reference to landmarks, aids to navigation, and depth sounding.

Direction is the orientation of an imaginary line joining one point to another without regard to the distance between them. Direction is measured in angular units of arc, measured in degrees, from a common reference whether it be true north or magnetic north. The usual reference is true north. The division of the degree may be either minutes and seconds or decimal fractions. Direction is written with three digits as in 000°.

Distance is the separation between two points without regard to direction. In navigation it is measured by the length of a line on the surface of the earth from one point to the other. It may be measured in units of yards, nautical miles or kilometers. The nautical mile is commonly used by navigators. The international nautical mile is 6076.12 feet. This is approximately 1.15 longer than the statute mile used on land.

Time is written as four digits in a 24 hour system; four minutes after midnight is 0004, 9:32 AM would be written as 0932 and 1:16 PM would be written as 1316.

Speed is defined as the rate of movement, and in navigation is usually measured in nautical miles per hour, or knots. The time element is included in the definition of “knot”; the use of knots (kts) per hour is incorrect. Speed is represented on your chart as “S”. Example S = 7.5 kts.

Dead Reckoning (DR) is the projection of a present position to an anticipated future position. This is done by using a previous known position and applying known direction, speed and distance covered. The term comes from deduced reckoning which was abbreviated ded reckoning. DR plots are done at a minimum of every hour or when ever you change course or speed. A new DR plot line is started each time a new “known position” is found.

Course is the direction of travel through the water or the direction a vessel is to be steered or is being steered. The course may be designated as true (T), magnetic (M), or compass (C). Course is always written in three digits and is followed by the abbreviation of its source. Example C = 090° T

Bearing is the direction of any place or object from a given point. It may be designated as true (T), magnetic (M), compass (C) or relative (R). It is always written in three digits and is followed by the abbreviation of its source. Example B = 270° T

Heading is the direction the vessel points or heads at any instant as read from your compass. It is always written in three digits. Example HDG = 270°

Fix is a known location at a specific time based on verifiable information and carrying a high degree of accuracy. Example:  0900

Running Fix is a known location at a specific time, with a lesser degree of accuracy than a fix. It is based on information obtained from a single event at two different times and plotted as a common time. Example:  R Fix 0900

Electronic Fix is a fix obtained from one or more electronic devices. Example:  0900