Navigation General · Radar Plotting
In a radar plot, 'CPA' stands for the:
- ACourse of the plotted aircraft
- BCompass point adjustment
- CClosest point of approach — the minimum range at which the contact will pass✓ Correct
- DCurrent position average
Explanation
CPA is the closest point of approach, the least distance the contact will pass from own ship if both maintain course and speed. TCPA is the time to reach it. These drive the decision on whether risk of collision exists.
Authority: Radar plotting terminology
Practice the full Navigation General bank
Free spaced-repetition quizzing across 2190 USCG exam questions — it schedules your reviews so the ones you miss come back until they stick.
Related Navigation General questions
- Radar Plotting
On a relative-motion radar display, a contact whose relative motion line points directly at your own ship's position (center) indicates:
- Radar Plotting
In the relative-motion triangle used to find a target's true course and speed, the line representing own ship's motion (the 'e-r' or 'WO' line) is laid off as:
- Dead Reckoning
A vessel departs a known position at 0800 on course 090°T at 12 knots. What is the DR position at 1100?
- Time-Speed-Distance
Using the 60 D = S × T formula, how long will it take a vessel traveling at 15 knots to cover 45 nautical miles?
- Time-Speed-Distance
A vessel travels 90 nautical miles in 6 hours. What is the vessel's speed?
- Dead Reckoning
Which of the following is the best definition of a Dead Reckoning (DR) position?