Action to Avoid Collision (Rule 8)

A target is inbound on a fine starboard bow, developing risk of collision. Apply Rule 8:

(a) AMPLE TIME act EARLY, while the other vessel still has plenty of room and time to read your intentions. In open water this is typically when TCPA is still 1020 minutes away (ranges of 48 NM for normal speeds); never in the last 23 minutes. "Ample" = enough time for the other ship to see, understand and react, and for you to verify your own action is working.

(b) SUBSTANTIAL readily apparent to the other vessel by eye AND on radar/AIS. A bold single alteration ( 20° of course, or 4 kt of speed) is vastly better than a series of small changes (Rule 8(b)).

(c) SAFE DISTANCE the manoeuvre must result in passing at a safe CPA (here 1 NM in open water).

(d) MONITOR keep checking CPA/TCPA after the action; be ready to alter further if the risk does not clear.

Make a single, bold, EARLY alteration and achieve CPA 1 NM.