US Sailing - Basic Cruising Exam 100%
Correct!!
Center of Effort - ANSWERThe focal point of the force of the wind on the sails.
Center of Lateral Resistance - ANSWERThe focal point of the force of the water on the underbody of
the boat.
How to find Center of Effort on the Main Sail - ANSWERDraw a line from the Clew to the midpoint of
the Luff. Draw another line from the Tack to the midpoint of the Leach. The intersection of these two
lines is the Center of Effort (of the Main Sail)
How to find the Combined Center of Effort - ANSWERMidpoint between the Center of Effort on the
Main and the Center of Effort on the Jib
Center of Lateral Resistance - ANSWERThe place on the hull such that if you were to push the boat
sideways, the boat would not pitch, yaw or roll.
What is the cause of Excess Weather Helm? - ANSWERCombined Center of Effort is too far aft of the
Center of Lateral Resistance
3 ways to correct Excess Weather Helm - ANSWER3 Corrections:
Reef the main
Ease the mainsheet
Move crew to windward
Reefing the main sail moves the Combined Center of Effort in which two directions? -
ANSWERCombined Center of Effort moves Forward and Down
What is the cause of Lee Helm? - ANSWERCombined Center of Effort is too far forward of the Center
of Lateral Resistance
2 ways to correct Lee Helm - ANSWER2 Corrections:
Reef the jib
If the main is reefed, shake out the reef
When does a Risk of Collision exist? - ANSWERExists if the bearing of an
approaching vessel is not changing.
Watch for a situation with:
Constant bearing +
Decreasing range
Correct!!
Center of Effort - ANSWERThe focal point of the force of the wind on the sails.
Center of Lateral Resistance - ANSWERThe focal point of the force of the water on the underbody of
the boat.
How to find Center of Effort on the Main Sail - ANSWERDraw a line from the Clew to the midpoint of
the Luff. Draw another line from the Tack to the midpoint of the Leach. The intersection of these two
lines is the Center of Effort (of the Main Sail)
How to find the Combined Center of Effort - ANSWERMidpoint between the Center of Effort on the
Main and the Center of Effort on the Jib
Center of Lateral Resistance - ANSWERThe place on the hull such that if you were to push the boat
sideways, the boat would not pitch, yaw or roll.
What is the cause of Excess Weather Helm? - ANSWERCombined Center of Effort is too far aft of the
Center of Lateral Resistance
3 ways to correct Excess Weather Helm - ANSWER3 Corrections:
Reef the main
Ease the mainsheet
Move crew to windward
Reefing the main sail moves the Combined Center of Effort in which two directions? -
ANSWERCombined Center of Effort moves Forward and Down
What is the cause of Lee Helm? - ANSWERCombined Center of Effort is too far forward of the Center
of Lateral Resistance
2 ways to correct Lee Helm - ANSWER2 Corrections:
Reef the jib
If the main is reefed, shake out the reef
When does a Risk of Collision exist? - ANSWERExists if the bearing of an
approaching vessel is not changing.
Watch for a situation with:
Constant bearing +
Decreasing range
