RV — Multi-Target Encounter (Rule 19)

RESTRICTED VISIBILITY (fog, heavy rain, snow). You cannot see either vessel visually you only have radar/AIS. Rule 19 governs: there is NO stand-on/give-way, and the "in sight" rules (1118) do NOT apply. Every vessel must act on her own account.

TWO targets are developing close-quarters situations simultaneously:
SIRIUS (Cargo) dead ahead, reciprocal course. Classic forward-of-beam encounter.
CASTOR (Tanker) port bow, closing from the west. Crossing from port.

HOW TO HANDLE MULTI-TARGET IN RV
(1) ASSESS both targets on the PPI check CPA, TCPA, bearing drift for each. Treat the one with the smaller CPA × shorter TCPA as the primary threat.

(2) PICK a manoeuvre that works for BOTH. Rule 19(d)(i) if you detect a target FORWARD of the beam (not overtaking), do NOT alter to PORT. Rule 19(d)(ii) do NOT alter TOWARD any target ABEAM or ABAFT the beam. Overlay those restrictions on the picture: a starboard alteration here is allowed for SIRIUS (she is forward of your beam) and does NOT violate 19(d)(ii) for CASTOR (she is on your port bow, not abeam/abaft). A port alteration is forbidden by 19(d)(i) for SIRIUS even though it would also clear CASTOR.

(3) MAKE IT SUBSTANTIAL Rule 8(b) applies in RV too. A readily-apparent turn is 30° and held long enough for the target to see it on their radar ( 60 s). In RV a speed reduction is often combined with the turn; see Rule 19(e) / 19(b) (safe speed).

(4) VERIFY after manoeuvring, re-check CPA to both. If either is still < 1 NM, act again. Final CPA 1 NM to BOTH.

Remember: in RV, passing another vessel at 0.5 NM means 510 seconds of warning if anything goes wrong. Open-water standard is 1 NM that gives you time.