Online Cruising Course
A. Planning a Cruise (II)
Make realistic projections about travel time over water and excursions in dinghy.
Plan an appealing itinerary:
Islands, bays or cays with attractions ashore.
Anchorages with scenic and natural features
Plan meals either at restaurants or on boat
Keep it simple on boat, eg pre-cook some food
Crystalize living patterns to the essential & delightful items & routines, & take & do those
If you can navigate, you can go anywhere in the BVI.
B. Piloting, or
Piloting is the art of getting there without going aground. To do so, you must learn to read a chart.
1. Reading a Chart. A chart has a lot of general information like a map. In addition, there is specialized information. Most importantly, the system of naviagational aids must be deciphered and understood.
Boayage System. The system of actual daymarkers and buoys on the water are represented on the chart by a system of symbols and letters. They tell you the location of shallow water (shoals) or deep water.
A buoy floats while chained to the bottom. A daymarker is fixed, usually on a piling.
The buoyage systems are the same for both the BVI and the U.S as well as the rest of the Caribbean and North and South America: the color red is used to mark the starboard (right side) side of the channel when approaching from seaward.
Thus the phrase: red, right, return.
Nuns are buoys with a red color and a pyramidal or conical shape, equivalent to red, triangular daymarkers. These have even numbers going up from the channel entrance.
Cans are buoys with a green color and a rectangular shape, equivalent to green, square daymarkers. These have odd numbers going up from the channel entrance.
Lighted flashing is indicated by the time interval in seconds and the color of the flash.
Interpreting depths read on chart. Don't rely on a number close to your boat's depth, since the chart has a scientific definition like mean, low water. Also these can be out of date due to shifting shoals.
Importance of local knowledge. When in certain situations, local knowledge can be vital.
It is importance to monitor your depth meter. You need to know the actual draft of your boat as it relates to the the depth meter reading. Will your boat go aground when the depth meter reads 5 feet?
2. Using a compass. If you know where you are and how to determine direction from a compass, you can go to a new location safely, i.e. without going aground.
There is true north and magnetic north as well as a deviation due to the effect of the boat itself on the compass.
In practice, it is often best to go from the magnetic reading on the chart to compass, which of course is a magnetic reading, and vice-versa, and ignore any deviation.
Using a compass rose and a parallel ruler. A chart has a compass rose with the true and magnetic headings nested in a circle.
Plotting a course. A line on a chart is called a course. This is the direction or true angle noted above the course line in degrees clockwise from north
Thus C120M or C120C means Course 120� magnetic (M) or compass (C), depending on where read, i.e. the source of the data.
The length of the course line is the measure of the actual distance you need to travel.
The speed in knots you intend to travel is noted below the course line preceded by S for speed.
A position is noted by a dot and half circle with the time noted nearby in military time
A course can be laid by pointing the boat to a mark or buoy and noting the compass heading on the chart. Plotting two such courses gives a "fix" at the "x" or intersection of the lines.
So knowing where you are and drawing a course line to that destination allows you to take a reading by transposing that course line to the compass rose and taking the magnetic heading. Then steer the boat on that heading.
To plot a course you need intellect, to keep it discipline. That means it is difficult to keep the boat on a constant heading for any lenght of time.
3. Use of depth meter
Importance of boat`s draft re boat going aground
Relating draft of boat to reading depth on chart
Knowing how depth meter is calibrated, ie to botton of keel, to waterline, or to otherwise
4. Maintaining windward margin of safety to shoals & shallow water
5. Getting off after going aground
Analysis: composition of reef or shoal, direction of "deep" water, boat position & eye of wind, ie any point of sail to get off
If being driven hard aground, quickly drop sails & motor off by backing
If tacking into shoal, use sails and wind to get off, including backwinding sails
Heel boat over by shifting crew weight
The possibility of kedging
Assess situation: damage to boat and likelihood of sinking, amount of pounding to keel by wave action, alternative sandy shores
Stuff any accessible leak with any available material
Turn on bilge pump and monitor bilge
Call charter base immediately
Move to shallow water if sinking
C. Cruise Destination:
Picking an anchorage.
Usually preferable to limiting & expensive marina slips
Have choice of surroundings for your boat
Pick a sheltered location in case of bad weather
Do not anchor in channel