You are steaming on course 168°T at a speed of 18 knots. At 1426 you sight a buoy bearing 144°T. At 1435 you sight the same buoy bearing 116°T. What is your distance off at the second bearing and predicted distance when abeam?

Question

You are steaming on course 168&deg;T at a speed of 18 knots. At 1426 you sight a buoy bearing 144&deg;T. At 1435 you sight the same buoy bearing 116&deg;T. What is your distance off at the second bearing and predicted distance when abeam?

Accepted Answer

Option B: 2.3 miles 2nd bearing, 1.8 miles abeam. Utilize the Bowditch 'Distance off at second bearing' formula. With a run of 2.7 miles between bearings (144 and 116 degrees), the change in bearing is 28 degrees. Applying the formula D = (Run * sin(relative bearing 2)) / sin(change in bearing) yields 2.3 miles, with 1.8 miles when abeam.

You are steaming on course 168&deg;T at a speed of 18 knots. At 1426 you sight a buoy bearing 144&deg;T. At 1435 you sight the same buoy bearing 116&deg;T. What is your distance off at the second bearing and predicted distance when abeam?

You are steaming on course 168°T at a speed of 18 knots. At 1426 you sight a buoy bearing 144°T. At 1435 you sight the same buoy bearing 116°T. What is your distance off at the second bearing and predicted distance when abeam?