VTS Navigation Systems 5

Question 1

What is the purpose of a Vessel Traffic Service (VTS) radar's 'gain' control?

Accepted Answer

To adjust the sensitivity of the radar receiver to detect weaker targets

Answer

Radar gain controls receiver sensitivity; increasing gain detects weaker or more distant targets, while reducing gain can eliminate noise and clutter.

Question 2

A vessel's AIS is transmitting a static draught of 8 meters, but the navigable channel has a controlling depth of 9 meters. What action should the VTS operator take?

Accepted Answer

Monitor the vessel and verify the charted controlling depth against current tidal conditions before advising

Answer

The operator must account for tidal state to determine actual underkeel clearance before determining whether the transit is safe and what advice to provide.

Question 3

What is 'sea clutter' on a radar display, and which control is used to reduce it?

Accepted Answer

Returns from waves near the vessel, reduced using the STC (Sensitivity Time Control) or sea clutter control

Answer

Sea clutter is caused by radar energy reflecting off wave surfaces close to the antenna, and the STC control progressively reduces gain at short ranges to suppress it.

Question 4

Under 33 CFR Part 161, which vessels are generally required to participate in a U.S. Vessel Traffic Service?

Accepted Answer

Power-driven vessels of 40 meters or more in length, certain towing vessels, and vessels carrying hazardous cargo

Answer

33 CFR Part 161 specifies that VTS participation is mandatory for power-driven vessels ≥40 meters, certain towing vessels, and vessels carrying hazardous materials in designated VTS areas.

Question 5

What is the function of a 'waypoint' in electronic navigation systems used by vessels reporting to VTS?

Accepted Answer

A predetermined geographic position used as a reference point along a planned route

Answer

A waypoint is a specific latitude/longitude position programmed into a navigation system to define the intended route, allowing automatic course guidance.

(VTS) Vessel Traffic Services Operator Exam Practice Test

(VTS) Vessel Traffic Services Operator Exam Practice Test

VTS Navigation Systems 5