Tidal Height Calculation Practice Pack, Worked Answers A4 PDF
Tides are where theory candidates lose marks, and the usual reason is that the practice runs out after three questions. Here are forty, all in one fictional training port, with a key that cannot disagree with the printed curve.
One fictional standard port, Port Selkie, whose fourteen day tide table, spring and neap curve pair, ordinate ladder and every answer are generated from a single two constituent harmonic model, so the key and the curve are the same object
TID-01 teaches the method end to end on an original boxed working grid, with the construction numbered 1 to 6, a panel of the six errors that cost marks, and an arrow diagram separating height of tide, charted depth and depth of water
Drill A, twelve questions on height of tide at a given time, and Drill B, twelve worked in reverse, including the flood and ebb answers and the window during which a depth is available
Drill C adds two fictional secondary ports and eight full double interpolations, taught as the Admiralty method and explicitly distinguished from the United States subordinate station system
Drill D is clearance, eight problems over charted depths and drying heights, then the rule of twelfths measured honestly against the same curve: 1.63 percent of range, not the alarmist figure usually quoted
TID-07 is the complete key with every intermediate value, so you can see which of the six stages went wrong; A4 and US Letter editions included
Most tidal practice material fails in one of two ways: it gives three questions and stops, or its answers quietly disagree with the curve it prints. This pack fixes both. Every value in it comes from one generator: the tide table is rounded to what you actually read, times to the minute and heights to 0.1 m, and the answers are then re-derived from those rounded figures. A careful student working the printed table and the printed grid cannot end up outside the stated tolerance because of an error in the key.
The port is fictional and says so on every sheet that carries its data. The fourteen day period is labelled Day 1 to Day 14 and is tied to no calendar year, so nothing here expires, and no real tide table, secondary port difference or charted depth is reproduced anywhere in the pack.
What's inside
Cover and how to use
TID-01 How the curve works: the construction numbered 1 to 6, six errors that cost marks, the datum arrow diagram
TID-02 The training port: fourteen day tide table, port levels, spring and neap curves at full working size, ordinate ladder
TID-03 Drill A, height of tide at a given time: twelve questions with a ruled working column for every stage
TID-04 Drill B, time for a given height: twelve questions, flood and ebb answers and the window
TID-05 Drill C, secondary ports: two fictional secondaries and eight full double interpolations
TID-06 Drill D, clearance and the rule of twelfths: eight problems and an honest error comparison
TID-07 Worked answers: every intermediate value, stated tolerances, two full specimen solutions
Combined pack PDF plus individual sheet PDFs, each in A4 and US Letter
Who it's for: Day Skipper and Yachtmaster theory candidates two weeks from the exam, and cruising skippers who work a drying harbour entry and want the clearance arithmetic to become automatic.
Licence: Personal and classroom use. You may share and repost this content, including commercially. You may not resell the files themselves or sell them on as a standalone product. Copyright remains with Maritime Master Limited.
Printing: Print at 100%, never fit to page. Keep TID-02 beside you while you work the drills, and photocopy it or trace the working grid rather than writing on the original. Greyscale by design; prints cleanly in black and white.
