At 2308 your position is LAT 41°12.7'N, LONG 72°22.8'W. You steer a course to make good 255°T from this position. At 2310 you receive a distress call from a vessel anchored 2.1 miles due north of Mattituck Inlet Light. If you change course at 2314, what is the course to steer per gyrocompass to arrive at the distress site if you allow 2° leeway for northerly winds, 3°E gyro error and correct your course for a current of 073°T at 1.3 knots?
• Plotting the distress position relative to Mattituck Inlet Light (2.1 miles due north) on the chart • Determining the vessel’s position at 2314 based on initial position, course made good 255°T, and time run • Applying sequential corrections: current, leeway, and gyro error to convert between true course and per gyrocompass (pgc)
• How far along course 255°T will you travel between 2308 and 2314 at your assumed speed, and what is your new position at 2314? • Once you have your 2314 position and the distress position plotted, what is the true course from your 2314 position to the distress site before applying any corrections? • In what order do you adjust this true course for current, leeway, and gyro error to obtain the per gyrocompass course, and does leeway for a northerly wind push your actual track to the left or right of your heading?
• Verify the distance run from 2308 to 2314 using ( \text{Speed} = \frac{\text{Distance}}{\text{Time}} ) and ensure you used the correct speed given in the larger exam problem set. • Double-check that the tidal current (073°T at 1.3 knots) is applied as a set and drift vector from your 2314 position toward the distress position, not just as a simple angle correction. • Confirm the final conversion from true course to per gyrocompass course: apply the 3°E gyro error correctly (remember, "Gyro least, error east" when converting).
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