Your vessel is on a course of 107° T at 16...

Question 1 of 2707066636eea28f7522a1c51b790

Your vessel is on a course of 107° T at 16 knots. At 0403 a light bears 129.5° T, and at 0426 the light bears 152° T. At what time and distance off will your vessel be when abeam of the light?

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Question 1 of 27070

Your vessel is on a course of 107° T at 16 knots. At 0403 a light bears 129.5° T, and at 0426 the light bears 152° T. At what time and distance off will your vessel be when abeam of the light?

🔍 Key Concepts

• Use the change in relative bearing to the light to find how long it will take until the light is exactly abeam (90° on either side from the bow) • Apply the idea of constant speed and straight-line motion: if course and speed are steady, bearing changes at a steady angular rate along that leg • Use your ship’s speed (16 knots) to turn the time from now until abeam into distance off

💭 Think About

• First convert the two bearings (129.5° T and 152° T) into relative bearings from your ship’s heading of 107° T. How many degrees of bearing change occurred between 0403 and 0426? • From that bearing change over 23 minutes, find how long it will take for the bearing to reach 90° relative (abeam). Is that to port or starboard based on your current relative bearings? • Once you know the time interval from the last observation (0426) to abeam, add it to 0426, then use Speed = Distance / Time to find how far you travel in that interval; that is the distance off when abeam.

✅ Before You Answer

• Be sure you subtract the ship’s heading (107° T) from each true bearing to get the correct relative bearings (keep them between 0° and 180° on the same side). • Carefully compute the time difference between 0403 and 0426 (in minutes) and use that with the bearing change to get the angular rate in degrees per minute. • When converting time to distance, remember that at 16 knots you travel 16 nautical miles in 60 minutes; scale that to the number of minutes from 0426 until abeam.