Hover or tap underlined Spanish terms to see their translation and exam tip.
El 25 de julio de 2020 navegamos a 7 nudos al rumbo de aguja 056º. Al ser HRB = 18h 00m nos encontramos en situación 35º 50,0' N, 006º 10,0' W. Calcular la situación al ser HRB = 19h 45m, sabiendo que la declinación magnética es 5º NW y el Desvío= –6º (menos).On 25 July 2020 we are sailing at 7 knots on compass course 056º. At ship’s clock 18h 00m we are at 35º 50.0' N, 006º 10.0' W. Calculate the position at 19h 45m, given that magnetic variation is 5º NW and deviation –6º (minus).
Show the answer
Correct answer: d) 35º 58.6' N; 005º 59.5' W
Why it is correct
Total correction = −5º − 6º = −11º, so true course = 056º − 11º = 045º. 1.75 h at 7 knots is 12.25 miles: 8.7′ north and 8.7 miles east, which is 10.7′ of longitude.
Why the others are not
- a) The working gives 35º 58,7′ N, 005º 59,3′ W, and this option does not match.
- b) The working gives 35º 58,7′ N, 005º 59,3′ W, and this option does not match.
- c) The working gives 35º 58,7′ N, 005º 59,3′ W, and this option does not match.
How to work it out in the exam
- Find the true course: true = compass + total correction.
- Distance = speed × time.
- Draw the course on the chart, measure the distance and read the position.
Where this question comes from
- Junta de Andalucía · 2020 · Convocatoria de e · PER Modelo B · question 45 Official paper · Official answer key
Try it: Navigation calculations
Pending instructor review. Machine translation, not reviewed.