OBS Navigation & Route Planning 2 — Questions and Answers
Question 1: What does a red buoy with an even number indicate in the US Aids to Navigation system?
- Leave it to your port (left) side when returning from sea
- Leave it to your starboard (right) side when returning from sea (Correct answer)
- It marks an obstruction below the surface
- It indicates a no-wake zone
Correct answer: Leave it to your starboard (right) side when returning from sea
Red even-numbered buoys mark the right side of a channel when returning from sea — remember 'Red Right Returning.'
Question 2: On a nautical chart, a number enclosed in parentheses next to a depth sounding indicates:
- A charted wreck depth
- A depth that has been reduced from a previous survey
- A dredged channel depth (Correct answer)
- The depth at mean high water
Correct answer: A dredged channel depth
Parenthesized depth figures on nautical charts denote dredged channel depths maintained to that level.
Question 3: A vessel is planning a coastal trip and must cross a shipping lane. What is the safest crossing procedure?
- Cross at an angle to minimize time in the lane
- Cross parallel to vessel traffic to blend in
- Cross at a right angle (90°) to the traffic flow as quickly as possible (Correct answer)
- Follow the shipping lane to the nearest exit point
Correct answer: Cross at a right angle (90°) to the traffic flow as quickly as possible
Crossing shipping lanes at a 90° angle minimizes your exposure time and makes your course predictable to large vessels.
Question 4: What is a 'waypoint' in modern GPS navigation?
- A mandatory check-in point with the Coast Guard
- A specific geographic coordinate saved as a navigation reference point (Correct answer)
- A marker buoy placed by the boater
- A fuel stop required by law on trips over 50 miles
Correct answer: A specific geographic coordinate saved as a navigation reference point
A waypoint is a stored GPS coordinate used to define a route or mark a destination.
Question 5: What does 'leeway' mean in navigation?
- Extra space given to anchored vessels when passing
- The sideways drift of a vessel caused by wind or current (Correct answer)
- The legal distance required between two boats underway
- A navigational shortcut through shallow water
Correct answer: The sideways drift of a vessel caused by wind or current
Leeway is the lateral drift of a vessel off its intended course due to the force of wind or current.
Question 6: When reading a compass bearing, a heading of 270° corresponds to which direction?
- North
- East
- South
- West (Correct answer)
Correct answer: West
On a 360° compass, 0°/360° is North, 90° is East, 180° is South, and 270° is West.
Question 7: What information does a 'Notice to Mariners' provide?
- Weather forecasts for the next 72 hours
- Updates on changes to aids to navigation and navigational hazards (Correct answer)
- Fishing regulations for specific waterways
- Required equipment lists for recreational vessels
Correct answer: Updates on changes to aids to navigation and navigational hazards
Notices to Mariners inform boaters of changes to charts, buoys, lights, and newly discovered hazards.
OBS Navigation & Route Planning 2
What does a red buoy with an even number indicate in the US Aids to Navigation system?