Radar Observer · ARPA — Vectors
On an ARPA, a true vector displayed on a target shows the target's:
- AMotion relative to own ship
- BActual course and speed over the ground/water✓ Correct
- CRange only
- DBearing only
Explanation
True vectors show each target's real course and speed (and own ship's), useful for identifying a target's aspect and intentions. Relative vectors instead show motion relative to own ship and point toward the CPA situation.
Authority: ARPA (USCG topic)
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