Boating Certification Test Vessel Operation & Control 3

Question 1

What is 'cavitation' on a boat propeller?

Accepted Answer

The formation and collapse of vapor bubbles on the propeller blades causing loss of thrust

Answer

Cavitation occurs when low pressure causes water to vaporize on the propeller surface; the collapsing bubbles reduce thrust and can damage the prop.

Question 2

When operating in fog, what sound signal should a power-driven vessel underway make?

Accepted Answer

One prolonged blast every 2 minutes

Answer

Rule 35 requires a power-driven vessel making way through the water to sound one prolonged blast at intervals of not more than 2 minutes in restricted visibility.

Question 3

What does 'freeboard' mean on a vessel?

Accepted Answer

The distance from the waterline to the top of the gunwale (deck edge)

Answer

Freeboard is the height of the hull above the waterline, which indicates how much reserve buoyancy remains before water can enter the vessel.

Question 4

You are traveling at planing speed and need to stop quickly. What is the most effective method?

Accepted Answer

Gradually reduce throttle to idle, then shift to reverse

Answer

Reducing throttle first to idle before shifting to reverse prevents engine and drive damage, and allows the hull to settle off plane before reverse thrust is applied.

Question 5

What is the effect of 'torque' from a single right-handed propeller on a vessel at low speed?

Accepted Answer

The stern tends to walk to port when in forward gear

Answer

A right-handed prop rotating clockwise in forward gear creates prop walk that tends to push the stern to port, affecting low-speed maneuvering.

Boating Certification Test Practice Test

Boating Certification Test Practice Test

Boating Certification Test Vessel Operation & Control 3