Tides Part 3: Secondary Port Calculation in Style
August 2, 2023 · 43 min · 1K views
What this video covers
The "Regina Sailing template" — a single A4 sheet consolidating tidal overview, standard port data, secondary port calculation, tidal curve notes, and anchoring calculations — is the central subject of this tutorial.0:06 Leon Schulz walks through a worked example of entering the tidal gate at Le Palais, Belle-Île, Brittany, where a drying height of minus 1 meter plus a 2-meter draft and 0.5-meter safety margin requires a minimum height of tide of 3.5 meters.1:07 Brest is the standard port; Belle-Île is the secondary port.12:26 The calculation corrects Brest's high-water time of 1512 for the secondary port difference and adds one hour for French summer time, yielding a local high water at approximately 1600.25:18 High-water height is interpolated between the 7-meter and 5.5-meter reference values to give 4.9 meters; low-water height is corrected by 0.4 meters to 1.1 meters.27:19 Time zone handling — UTC, Central European time, BST, and Reeds' "UT minus one" convention — is explained step by step, with a personal anecdote about missing a lock opening due to time-zone confusion.5:40 Tidal apps including the Imray Tide Planner and TimeZero are noted as useful but unreliable to the last centimeter, particularly for summer-time offsets and passage planning beyond a few days.35:58
Boats in this video
More from Leon Schulz, Reginasailing
From Leon Schulz, Reginasailing — see the channel’s boat, crew, and every analyzed video.
The Sailing Directory Newsletter
One email with the fleet's best finds — the moments, boats, and stories worth your watch time. Enter your own address to get your own copy.