Hover or tap underlined Spanish terms to see their translation and exam tip.
A HRB= 11h 15m del 21 de noviembre de 2020, nos encontramos en situación verdadera 35º 55,0' N, 005º 50,0' W y damos rumbo al Puerto de Barbate (faro de tierra) a 8,5 nudos de velocidad. Calcular el rumbo de aguja y la HRB de llegada, sabiendo que la declinación magnética es 6º NE y el Desvío = +4º (más).At 11h 15m on 21 November 2020 in true position 35º 55.0' N, 005º 50.0' W, you set course for the Port of Barbate (shore light) at 8.5 knots (variation 6º NE, deviation +4º). Find the compass course and ETA:
Show the answer
Correct answer: a) Ra = 335º, HRB = 13h 15m
Why it is correct
From 35º 55.0′ N, 005º 50.0′ W to Barbate light, Rv = 345º and distance d = 17.0 miles. With Ct = +6º + 4º = +10º, compass course is Ra = 345º − 10º = 335º; at 8.5 knots the run takes 17.0 / 8.5 = 2h 00m, arriving at 13h 15m.
Why the others are not
- b) Does not properly apply Ra = 345º − 10º = 335º or the 2-hour run time (17.0 / 8.5).
- c) Does not properly apply Ra = 345º − 10º = 335º or the 2-hour run time (17.0 / 8.5).
- d) Does not properly apply Ra = 345º − 10º = 335º or the 2-hour run time (17.0 / 8.5).
How to work it out in the exam
- Measure on the chart the true course (Rv = 345º) and distance (17.0 miles) to Barbate.
- With Ct = +10º, Ra = 335º; divide 17.0 / 8.5 = 2 h to arrive at 13h 15m.
Where this question comes from
- Junta de Andalucía · 2020 · 3ª convocatoria · PER Modelo A · question 44 Official paper · Official answer key
- Junta de Andalucía · 2020 · 3ª convocatoria · PER Modelo B · question 42 Official paper · Official answer key
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Pending instructor review. Machine translation, not reviewed.