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Plot Log
Practice Sheet No. 1, Heron Sound (invented, not for navigation) 34 41 22 38 29 18 27 44 12 21 19 N VAR 7°W (invented) Heron Sound Heron Point Tern Island Westfield Kittle Gannet Rock Fl W 4s 52ft 14M TR TANK SPIRE STACK Dbn 1 2 3 HS 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Border scale: nautical miles (1 nm = 10 ticks) PRACTICE SHEET No. 1 · HERON SOUNDInvented for practice · NOT FOR NAVIGATION · Plotroom 0950
Dividers: drag from one point to another on the chart

Start a drag on a charted object or buoy and it snaps to it. The readout gives the true bearing (and magnetic, 7°W) from where you start to where you are, and the distance in nautical miles.

Skill 5 · Set and driftProblem 231001

Your 1025 fix is not where the DR said: find the set and drift.

At 0950 your fix is 257°T, 2.8 nm from Gannet Rock daybeacon. You steer 293°T at 4.9 kn through the water. At 1025 a new fix puts you 260°T, 3.6 nm from Tern Island tower.

Plot the 1025 DR, then find the current: set (the true direction the water moved you, from the DR to the fix) and drift (its speed in knots over the 35 minutes).

Tolerance: 4° and 0.15 kn.

Given
0950 fix257°T, 2.8 nm from Gannet Rock daybeacon
Course and speed293°T, 4.9 kn
1025 fix260°T, 3.6 nm from Tern Island tower
°T
kn
New problem

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