Boat handling basics
This is the first in a series of the Boat Handing Series and it outlines the basic ideas which you will use in operations described in the other brochures in this series.
Remember, you can't become a good boat handler by reading - so practice on the water.
Always choose conditions that suit your boat and your experience.
1. Loading your boat
The way you load your boat affects the way it will handle. Remember:
(a) Stow the load low in the boat
(b) Lash equipment to prevent movement
(c) Distribute the load evenly
Freeboard is the most important thing to remember when you load your boat. If you overload, if the load moves or is not properly distributed, you reduce freeboard and risk swamping your boat.
Water lying in the bottom of the boat also acts like a shifting load. As the boat rolls from side to side, the water moves and reduces freeboard. Always bail water out immediately.
Your boat should also be fitted with buoyancy so that if the worst happens, it will not sink.
Check the condition of buoyancy regularly - it may save your life.
Remember to follow a pre-start checklist before you go out in your boat.
2. Motor Trim
Load distribution affects a boat's trim when it is stationary; motor trim affects a boat's trim when it is under way.
What is correct trim?
Obviously, both the examples above are at opposite extremes. Correct trim is in the middle, where the bow is clear of the water, but the boat handles well without lifting and slamming continuously
How is trim adjusted?
On smaller motors, you must adjust the trim before setting out. This is done by moving the trim pin located near the mounting bracket. There are normally four or five alternative positions.
On large motors, trim is adjusted hydraulically when the boat is under way. Many large vessels also have a gauge at the helm to indicate the trim position.
3. Steering with a single outboard
An outboard differs from a conventional vessel because the rudder and propeller are contained in one unit. Also, because the rudder and the propeller turn together, the direction of the propeller's thrust is altered without the aid of the rudder.
Most propellers are right-handed - that is, they rotate clockwise when looking forward. We all know that the propeller makes the thrust that pushes the vessel ahead or astern - but it is important to realise that it also pushes it sideways.
As the right-hand propeller moves through the water, it tries to "cartwheel" sideways like a paddle wheel, causing the stern to move to starboard and the bow to port when going ahead, as shown.
Conversely, when going astern the bow swings to starboard and the stern to port. You can take advantage of these transverse movements when you manoeuvre your boat; this is explained in detail later in this series.
4. Effects of wind and tide
When a boat slows down, its ability to manoeuvre is reduced. When it is windy, this becomes worse because the wind also alters the boat's course.
Wind affects various vessels differently:
Wind can only affect the part of the vessel where there is a large area to blow against.
The cabin will be exposed to the wind and the boat will swing to port; a boat with an aft cabin will swing to starboard.
Remember, too, that even if you maintain your course, the boat will "crab" sideways in a wind.
Tide has the same effects as wind, but it is the underwater surfaces which cause them. You must understand the effects of tide and compensate for them.
Brought to you by Marine and Safety Tasmania