You are chief mate on a vessel fitted with a bow thruster. The pilot asks for "bow thruster to port" during a berthing manoeuvre but you notice the vessel's speed is 3 knots. What do you say and why?

A. The bow thruster is the pilot's control — the chief mate should not advise on its use. The pilot knows the vessel's characteristics from the pilot card and needs no advice from the bridge team.

B. Apply the bow thruster as requested. The pilot is in charge of the manoeuvre and the chief mate should not contradict the pilot's orders — the pilot decides when to use the bow thruster.

C. Bow thrusters work at any speed — speed has no effect on bow thruster effectiveness. Apply full thruster as ordered.

D. BOW THRUSTER SPEED LIMITATION — CHIEF MATE RESPONSE: ACTION: Advise the pilot: "Pilot, bow thruster is limited above approximately 2 knots — it will have little effect at current speed of 3 knots. Recommend reduce speed before applying bow thruster." WHY BOW THRUSTERS LOSE EFFECTIVENESS WITH HEADWAY: A bow thruster works by projecting a transverse water jet from a tunnel through the ship's bow. At speeds above approximately 1.5-2 knots: (a) The forward motion of the hull disturbs the water ahead of the bow thruster outlet; (b) The transverse jet is swept aft by the relative water flow; (c) Thrust efficiency drops rapidly — at 3 knots a typical bow thruster may be producing only 30-50% of its rated thrust; (d) The effect becomes negligible above approximately 4 knots. CORRECT PROCEDURE: (1) Reduce speed below 2 knots before requesting bow thruster; (2) Inform the pilot of the vessel's specific speed limit for effective bow thruster use (on the pilot card); (3) Use engine ahead/astern movements combined with rudder at higher speeds for directional control instead. CHIEF MATE COMMUNICATION: calmly advise the pilot — the chief mate has authority and responsibility to provide the pilot with accurate vessel-specific information.

A. Bridge engine control is tested only at drydock. Between drydocks, the engineer officer of the watch is solely responsible for engine operations and the chief mate has no role in engine testing.

B. BRIDGE ENGINE REMOTE CONTROL — PRINCIPLES AND TESTING: OPERATING PRINCIPLE: Modern vessels have a telegraph system that allows the bridge to command propulsion from three positions: (1) Bridge wing (port and starboard); (2) Bridge centre console (primary); (3) Engine room local control (manual override). The system typically uses an electronic or electro-pneumatic telegraph — the bridge moves the telegraph lever and the engine room control room (or automated system) responds with matching engine movement. REMOTE CONTROL TYPES: (a) Bridge full control: bridge moves engine telegraph → ECR or UMS system automatically adjusts fuel injection, ahead/astern valve, and RPM; (b) Telegraphed control: bridge signals intention, engine room carries out manually; (c) CPP (Controllable Pitch Propeller): blade pitch changes rather than engine RPM — bridge pitch lever directly adjusts thrust. PRE-DEPARTURE TEST: (1) Notify engine room of impending test; (2) Test both bridge wing controls and centre console — move telegraph full range ahead/stop/astern; (3) Confirm ECR repeater matches bridge telegraph position; (4) Test emergency stop function; (5) Confirm steering gear tested (SOLAS V/26 — 12 hours before departure); (6) Log all tests with times; (7) Confirm with chief engineer "engines ready for manoeuvring."

C. The bridge telegraph is advisory only. The engine room carries out all engine movements independently — the bridge telegraph is a communication tool, not a control system.

D. Engine testing before departure is done by increasing to full ahead for 5 minutes then stopping. Other tests are the chief engineer's responsibility and are covered by the SMS.

A. Wake the master for every UMS alarm. Only the master has authority to decide whether a UMS alarm requires action at night — the OOW should not make this assessment.

B. All UMS alarms are exclusively the duty engineer's responsibility. The bridge OOW should silence the alarm and wait for the engineer to respond — there is no bridge action required.

C. UMS ALARM — BRIDGE OOW/CHIEF MATE RESPONSIBILITIES: UMS BACKGROUND: SOLAS II-1/46-54 and the UMS Code (MSC/Circ.645) allow machinery spaces to be operated without continuous manning when the vessel meets prescribed equipment and alarm standards. The engineer is on call, not in the machinery space. OOW BRIDGE ACTIONS ON UMS ALARM: (1) ACKNOWLEDGE the alarm on the bridge alarm panel — this stops the audible alarm but keeps the visual; (2) RECORD: alarm type, time, and acknowledge time in the logbook; (3) CONTACT the duty engineer officer — give the alarm description and location; (4) MONITOR the alarm: if a second alarm follows rapidly (cascade alarms), or if a HIGH PRIORITY alarm activates (blackout, main engine shutdown, steering failure) — take immediate navigational action as appropriate; (5) DO NOT SILENCE AND IGNORE: the alarm system requires that alarms are responded to — an unresponded-to alarm triggers escalation to the next person on the call list; (6) HIGH PRIORITY ALARMS: main engine slowdown/shutdown → notify master, consider navigational implications (vessel now drifting or under reduced power); (7) Document all alarms, response times, and engineer actions taken in the UMS alarm log. CHIEF MATE UNDERSTANDING: must know which alarms require navigational response vs engineering response.

D. UMS alarms can be safely ignored for 30 minutes before escalation. The engineer's call response time is 30 minutes under SOLAS and the OOW should not contact the engineer before this period expires.