SEAMANSHIP Flashcards
What are the two types of keels?
Bar keel - which extends below the boat. Offers more protection and strength but has a deeper draft.
Flat plate keel - is built within the vessels hull and does not increase vessels draft.
What are the three basic hull types?
Displacement - pushing water (tug)
Planing - rides on top of water (small boat)
Semi-displacement - a combo of both displacement and planing (yacht)
What are the 3 different types of rudders?
Balanced - rudder post attaches in the middle of the blade
Semi-balanced - more than half of the blade is aft of rudder post.
Unbalanced - blade is entirely aft of rudder post.
What is the front edge of a blade on a prop called?
Leading edge
What is the back edge of a blade on a prop called?
Trailing edge
The upper edge on a boats side is called?
Gunwale (pronounced “gun-ul”
What is a temporary list caused by external forces called?
Heel
___________ - force of water on the hull acting in a vertical or upward force pushing it up, causing the vessel to float.
Buoyancy
___________ - the Point at which the weight of the boat acts vertically downward.
Center of gravity
__________ - permanent leaning of a vessel.
List
What are dynamic forces?
The surroundings effect on the ship/boat.
Sea / wind / current
What are static forces?
Boats effect on itself
Difference in weight distribution and buoyancy.
Block and tackle.
Using a single standing block and a single moving block is called __________ tackle.
Gun Tackle
Block and tackle.
Using a single standing block and a double moving block is call a ________ tackle.
Luff Tackle.
Block and tackle.
Using a double standing block and a double moving block is called a ________________________.
Twofold purchase.
Block and tackle.
A tackle is “two blocked” when the blocks are?
Jammed together
___________ - To be thrown broadside to surf or heavy sea.
Broach
Equation for Fahrenheit to Celsius?
Subtract 30 ÷ 2
Top of a wave, breaker, or swell.
Crest
To move through the water sideways.
Crab
The difference between true and magnetic north?
Variation
The amount of deflection, influenced by a vessel and electronics on the compass.
Deviation
What are the three basic types of waves?
Spilling, plunging and surging
A Small line attached to the small end of a drogue, so the device can be turned around to be retrieved.
Tripping line
The valley between waves is called?
Trough
A current that runs parallel to the shore and inside the breakers as a result of the water transported to the beach by the waves.
Longshore current
A current created along a Long Beach or reef surf zone due to water from waves hitting the beach and traveling out to the sides and parallel to the shore line, creating a long shore current that eventually returns to sea.
Rip current
Warm moist air moving over cold water or land creates.
Advection fog
