Question 1

Compared with neaps, a tidal gate over a bar at SPRINGS gives you…

Accepted Answer

A narrower window — the tide falls further and faster — The twelfths apply to a bigger range, so the metres-per-hour rate is nearly double and the height drops below your minimum sooner each side of HW.

Question 2

A passage contains one hard tidal gate. You plan…

Accepted Answer

Backwards from the gate — it fixes the timetable — The gate fixes when you must be there; distance and speed then fix departure. Everything else fits around it.

Question 3

A “tidal gate” on a passage is…

Accepted Answer

A stretch passable or sensible only at certain states of tide — Headland races, shallow bars, strong narrows — arrive at the wrong time and you wait or fight it. The plan times departure backwards from the gate.

Gates, sills and the spring trap

This lesson is part of a paid course