Hover or tap underlined Spanish terms to see their translation and exam tip.
A HRB = 09:00 nos encontrarnos al Sur verdadero del Faro de la Isla de Tarifa y en la oposición de los Faros de Punta Cires y Punta Camarinal. Situados, damos rumbo a pasar a 5 millas del faro de Punta Camarinal. Declinación magnética = 5º NW y Desvío de la aguja = +12º (más). Calcular el rumbo de aguja.At 09:00 ship’s time, located due South true of Isla de Tarifa lighthouse on the opposition of Punta Cires and Punta Camarinal, you set course to pass 5 miles off Punta Camarinal (variation = 5º NW, deviation = +12º). What is the compass course?
Show the answer
Correct answer: c) 273º
Why it is correct
Intersecting the meridian due south of Isla de Tarifa (005º 36.6′ W) with the Punta Cires–Punta Camarinal opposition fixes the vessel at 35º 59.0′ N, 005º 36.6′ W. The tangent to pass 5 miles off Punta Camarinal gives Rv = 280º; with Ct = −5º + 12º = +7º, Ra = 280º − 7º = 273º.
Why the others are not
- a) Does not apply Ra = Rv − Ct with Rv = 280º and Ct = +7º.
- b) Does not apply Ra = Rv − Ct with Rv = 280º and Ct = +7º.
- d) Does not apply Ra = Rv − Ct with Rv = 280º and Ct = +7º.
How to work it out in the exam
- Fix the intersection of due south of Tarifa with the Cires–Camarinal opposition and draw the tangent to the 5-mile arc off Camarinal: Rv = 280º.
- Compute Ct = −5º + 12º = +7º and Ra = 280º − 7º = 273º.
Where this question comes from
- Junta de Andalucía · 2016 · 3ª convocatoria · PER Modelo A · question 45 Official paper · Official answer key
- Junta de Andalucía · 2016 · 3ª convocatoria · PER Modelo B · question 42 Official paper · Official answer key
Try it: Navigation calculations
Pending instructor review. Machine translation, not reviewed.