Sailing Passage & Anchoring Pack

Anchoring, under-keel clearance and passage planning

Anchoring, under-keel clearance and passage time, with the numbers the calculators stop short of. Minimum scope by bottom and length of stay. What the anchor is actually holding — load goes as the square of the wind, so 40 knots pulls four times what 20 does — and the wind at which your chain comes bar-taut and stops being the spring you were relying on: for 8 mm at 6:1 that is about 27 knots. Then under-keel clearance, where the Rule of Twelfths cannot be trusted, and what a passage to windward really takes. 9 pages, printable, with a fill-in passage plan and anchor log.

Look inside

Two full pages from the pack, exactly as printed. Click either to read it at full size before you decide.

What is in it

• Minimum scope by bottom and length of stay - chain and mixed rode
• What each bottom does, and the two that often will not hold at all
• The steady pull on your anchor, by wind speed and windage — and why doubling the wind quadruples it
• The wind at which your chain comes bar-taut and stops being a spring, by chain size and scope
• Why veering more chain buys more than buying heavier chain
• Fill-in sheet for your own boat's windage, chain and scope
• Swing-room tables: the water you actually sweep, not the rode length
• Anchoring order of work, and a before-you-turn-in checklist
• Water needed above charted zero, by swell and the margin you keep
• Where the Rule of Twelfths cannot be trusted, and what to use instead
• Real passage times by windward fraction and tide
• Fill-in passage plan and anchor log

The pack complements the free calculators — they do the arithmetic, it carries the figures they cannot know.