Passage Planning Offshore Flashcards

How should tidal streams be factored into an offshore passage plan?

Answer: Calculate tidal streams for each leg using tidal stream atlases or diamonds, plotting the tidal vectors to determine the course to steer and estimated speed over ground

Tidal streams must be calculated for the entire passage, not just near shore. Using tidal stream atlases or diamonds, the navigator plots tidal vectors to determine the course to steer and estimated ground track for each hour of the passage.

What role does the 'pilot book' play in offshore passage planning?

Answer: It provides detailed descriptions of coastlines, harbours, approaches, dangers, anchorages, and local conditions that supplement chart information

Pilot books (sailing directions) provide detailed written descriptions of coastlines, harbours, approaches, recommended tracks, dangers, tidal information, facilities, and local knowledge that supplements the information shown on charts.

When planning a Channel crossing, why is it important to account for Traffic Separation Schemes (TSS)?

Answer: TSS in the Dover Strait and other areas carry legal obligations for crossing vessels, including crossing at right angles and not impeding vessels in the traffic lanes

The TSS in the English Channel (particularly Dover Strait) is one of the busiest shipping lanes in the world. Crossing vessels must comply with Rule 10 of COLREGs: cross at right angles, do not impede lane traffic, and allow extra time for the crossing.

What is the purpose of filing a 'passage plan' with a shore contact?

Answer: So that someone ashore knows your intended route, ETA, and can raise the alarm if you fail to arrive or make contact within the agreed timeframe

Leaving a passage plan with a responsible shore contact ensures someone will notice if you don't arrive on time and can alert the coastguard. Include route, ETA, crew details, vessel description, and agreed check-in schedule.

How should crew briefing be conducted before an offshore passage?

Answer: All crew should be briefed on the passage plan, safety equipment locations, emergency procedures, watch system, seasickness management, and individual responsibilities

A thorough crew briefing covers: the passage plan and route, safety equipment (liferaft, flares, fire extinguishers, MOB gear), emergency procedures, watch system, seasickness prevention, communication protocols, and each person's duties.

What is 'waypoint navigation' and what are its limitations offshore?

Answer: Navigating from one GPS waypoint to the next — limitations include over-reliance on electronics, waypoint errors, failure to account for hazards between waypoints, and loss of situational awareness

While GPS waypoint navigation is valuable, over-reliance on it can lead to complacency. Limitations include: waypoints may be incorrectly entered, the route between waypoints may pass over hazards, and electronic failure leaves the crew without a backup plan.