USCG Exam PracticeRunning fix from a single object
A vessel is on course 270°T at 9 knots. At 1400 the navigator takes a bearing of 350°T to a lighthouse. At 1430 a second bearing to the same lighthouse is 020°T. To construct the running fix, the navigator advances the 1400 LOP along the DR track. What distance is used to advance that LOP?
- A. 9.0 nautical miles
- ✓ 4.5 nautical milesCorrect
- C. 3.0 nautical miles
- D. 6.0 nautical miles
Why B is correct
Elapsed time is 30 minutes (0.5 hours). Distance run = 9 knots × 0.5 hours = 4.5 nautical miles. The first LOP is advanced 4.5 nm along the DR track in the direction of course 270°T. (Bowditch Ch. 7 §708, Ch. 8 §801)