You need to cross the Dover Strait Traffic Separation Scheme from the French coast to the English coast. Explain your obligations under Rule 10.

A. Cross the TSS at the narrowest point to minimise time in the lane. The crossing point is more important than the crossing angle.

B. When crossing a TSS, the normal crossing rules apply — keep to starboard and give way to vessels in the lane. Vessels in the lane have right of way over crossing vessels.

C. RULE 10 — CROSSING THE DOVER STRAIT TSS: The Dover Strait TSS is one of the busiest shipping lanes in the world. RULE 10 CROSSING OBLIGATIONS: (1) Rule 10(c): "A vessel shall so far as practicable avoid crossing traffic lanes but if obliged to do so shall cross on a heading as nearly as practicable at right angles to the general direction of traffic flow." — CROSS AT 90°. Not your track or course made good — your HEADING must be 90° to the traffic flow. This minimises your time in the lane; (2) CROSSING VS PROCEEDING ALONG: if you are not proceeding along the TSS, you may cross it. But you must use the 90° rule; (3) Rule 10(d): "Inshore Traffic Zones shall not normally be used by through traffic." The coastal traffic zone between the TSS and the coast is for local traffic; (4) CROSSING VESSEL STATUS: when crossing a TSS, your vessel is not in the "lane" — you are crossing it. The COLREG priorities between your vessel and lane vessels apply normally; (5) AIS AND VHF: in the Dover Strait, Gris Nez Traffic and Dover Coastguard maintain continuous VHF watch. Announce your intentions before crossing; (6) PRACTICAL EXAMPLE: if the general direction of traffic in the northbound lane is 060°, you must steer a heading of approximately 150° (90° to the right of traffic flow). Your actual track may be different due to set and drift — but your HEADING must be 90°; (7) COURSE MADE GOOD: if you need to account for a 2-knot tidal set, adjust speed and heading to maintain the 90° heading while the track drifts slightly — but the heading rule is paramount.

D. A vessel crossing a TSS must use the designated crossing points marked on the chart. Crossing outside the designated points is prohibited.

A. A NUC vessel is the stand-on vessel in all situations. Your vessel must maintain course and speed and allow the NUC vessel to take avoiding action.

B. NUC VESSEL — CM RESPONSE: The vessel displaying TWO BLACK BALLS (day) / TWO ALL-ROUND RED LIGHTS vertical (night) is a NOT UNDER COMMAND (NUC) vessel. COLREG Rule 27(a): "A vessel not under command shall exhibit two all-round red lights in a vertical line where they can best be seen; two balls or similar shapes in a vertical line where they can best be seen." DEFINITION (Rule 3(f)): "Not under command means a vessel which through some exceptional circumstance is unable to manoeuvre as required by these rules and is therefore unable to keep out of the way of another vessel." Typical causes: main engine failure; steering gear failure; loss of power. YOUR OBLIGATIONS: (1) YOUR VESSEL MUST KEEP CLEAR: a NUC vessel cannot take avoiding action. The NUC display is an advisory signal — YOU must manoeuvre. Rule 18(a): "A power-driven vessel underway shall keep out of the way of: a vessel not under command." (2) EARLY AND SUBSTANTIAL ACTION: Rule 16 — "Every vessel which is directed to keep out of the way of another vessel shall, so far as possible, take early and substantial action to keep well clear." (3) MONITOR CLOSELY: even if CPA is safe, continue to monitor. A NUC vessel may drift with current or alter if she partially regains power; (4) VHF: brief communication to confirm her situation and intentions may be appropriate; (5) CALL MASTER: at night in a crossing or overtaking situation with a NUC vessel — consider calling master. The situation could deteriorate rapidly if she is drifting; (6) ADDITIONAL LIGHT: if the NUC vessel is also making way — she shows sidelights in addition to the red lights.

C. Two black balls means the vessel is at anchor. You should maintain your course but pass with caution at a safe distance as anchored vessels are not give-way.

D. The NUC vessel's situation is a temporary inconvenience. The rules of the road between power-driven vessels apply normally — the vessel on the port side gives way.

A. RAM vessels have the right of way over all other vessels including sailing vessels. As a power-driven vessel, you must always give way to RAM.

B. Ball-diamond-ball is the day signal for a vessel engaged in fishing. At night, a fishing vessel shows red over white all-round lights.

C. RAM VESSEL — IDENTIFICATION AND LIGHTS: The vessel displaying BALL-DIAMOND-BALL (day) and ALL-ROUND RED-WHITE-RED (night) is RESTRICTED IN ABILITY TO MANOEUVRE (RAM). COLREG Rule 27(b): "A vessel restricted in her ability to manoeuvre, except a vessel engaged in mineclearing operations, shall exhibit: three all-round lights in a vertical line where they can best be seen. The highest and lowest of these lights shall be red and the middle light shall be white; three shapes in a vertical line where they can best be seen. The highest and lowest of these shapes shall be balls and the middle one a diamond." WHEN MAKING WAY ADDITIONALLY: masthead light(s), sidelights, and sternlight — in addition to the RAM signals. TYPICAL RAM VESSELS: a dredger; a vessel engaged in surveying or hydrographic work; a vessel engaged in buoy laying operations; a cable-laying vessel; a vessel conducting replenishment at sea (RAS); a tug engaged in a towing operation that severely restricts her ability to manoeuvre; a vessel engaged in diving operations; a minelayer. YOUR OBLIGATIONS: Rule 18(b): "A power-driven vessel underway shall keep out of the way of a vessel restricted in her ability to manoeuvre." Your vessel must keep clear. A RAM vessel with obstruction on one side: Rule 27(d) — if the vessel's ability to manoeuvre is restricted due to work on one side, she shows additional lights/shapes to indicate the safe side to pass.

D. Three vertical lights (red-white-red) are shown by a hovercraft operating in the non-displacement mode. This vessel should be treated as a power-driven vessel.