What causes overfalls and tide races near headlands and what precautions should a passage plan include?

A. Overfalls form where fast tidal streams pass over uneven sea bed — near headlands where the stream accelerates and at shallow banks where the current interacts with depth. Precautions: plan to pass headlands at slack water or with a fair tide; give headlands a wide berth; note overfall areas on the chart (symbol: short wavy lines)

B. Tidal races are only found in Scottish waters and the Channel Islands

C. Passing close to a headland is always safer than going around as it reduces distance

D. Overfalls only occur in Force 5 or above — calm conditions are always safe near headlands

A. The almanac page for the port read below decks as you approach

B. A pilotage plan is only required for commercial vessels entering commercial ports

C. Large-scale chart of the harbour; tidal height at entry time; leading lines and transit bearings; light characteristics of key marks; VHF channel for port/marina; depth of bar or shallowest point; hazards on approach; abort decision point; a sketch on a card visible at the helm

D. Only the GPS waypoints for the harbour entrance — GPS provides all other information

A. Leading lines are depth contours marked on the chart to guide vessels along the 5m contour

B. Leading lines require a radar to use — they cannot be identified visually

C. Only day marks can serve as leading lines — lit structures cannot be used at night

D. Two charted marks aligned in transit indicate the centre line of the safe channel. Keep both marks in line (one above the other) to maintain the correct track. If the marks separate, steer to bring them back in line. The bearing of the transit is fixed and compass-error-free