Maritime and Marine Marine Navigation and Charting

Question 1

What is the primary reference level (datum) used for depth soundings on US nautical charts?

Accepted Answer

Mean Lower Low Water (MLLW)

Answer

Mean High Water

Answer

Mean Sea Level

Answer

Mean Low Water Springs

Question 2

On a US chart using the lateral buoyage system, what does a green buoy with an odd number indicate?

Accepted Answer

Port side of the channel entering from seaward

Answer

Starboard side of the channel entering from seaward

Answer

A midchannel safe water mark

Answer

A special-purpose hazard marker

Question 3

Which nautical chart scale would a mariner use for the most detailed view of a harbor or anchorage?

Accepted Answer

Harbor chart (1:50,000 or larger)

Answer

Sailing chart (1:600,000 or smaller)

Answer

General chart (1:150,000–1:600,000)

Answer

Coastal chart (1:50,000–1:150,000)

Question 4

What is magnetic variation as shown on a nautical chart used to calculate?

Accepted Answer

The difference between true north and magnetic north at that location

Answer

Compass deviation caused by onboard ferrous metal

Answer

The effect of current on the vessel's course

Answer

The rate of change of the compass bearing over time

Question 5

On a nautical chart, what does an anchor symbol enclosed in a circle indicate?

Accepted Answer

A recommended anchorage area

Answer

A prohibited anchorage area

Answer

A mandatory anchoring zone requiring a permit

Answer

A commercial vessel-only anchorage

Question 6

What is a navigational 'range' used for?

Accepted Answer

Aligning two fixed marks to guide a vessel along a safe track

Answer

Measuring the maximum radar detection distance

Answer

Indicating the effective broadcast distance of a radio beacon

Answer

Describing the tidal range between high and low water

Question 7

What is the purpose of a 'Notice to Mariners' published by the National Geospatial-Intelligence Agency (NGA) and USCG?

Accepted Answer

To issue corrections and updates to nautical charts and publications

Answer

To announce new vessel registration requirements

Answer

To broadcast weather forecasts for coastal waters

Answer

To list commercial shipping traffic schedules