What is ARPA and its primary function?

What is ARPA and its primary function?

• A. Automatic Radar Plotting Aid; it tracks targets, computes CPA/TCPA, and predicts their tracks
• B. Automatic Radar Position Analysis; it estimates wind drift
• C. Automated Radar Processing Array; it filters clutter
• D. Active Radar Prediction Apparatus; it predicts weather

Answer: (A)

ARPA stands for Automatic Radar Plotting Aid. Its main role on a vessel is to automate the tracking of radar targets, display their tracks, and assess collision risk by calculating the closest point of approach and the time to that point (CPA/TCPA), while projecting each target’s future position. This predictive tracking helps you decide whether to alter course or speed to avoid a collision. Other options describe functions outside ARPA’s primary purpose, such as wind drift estimation, weather prediction, or general radar clutter filtering.

ARPA stands for Automatic Radar Plotting Aid. Its main role on a vessel is to automate the tracking of radar targets, display their tracks, and assess collision risk by calculating the closest point of approach and the time to that point (CPA/TCPA), while projecting each target’s future position. This predictive tracking helps you decide whether to alter course or speed to avoid a collision.

Other options describe functions outside ARPA’s primary purpose, such as wind drift estimation, weather prediction, or general radar clutter filtering.