Hover or tap underlined Spanish terms to see their translation and exam tip.
En posición GPS l: 36º 00,00`N L: 005º 50,00`W damos rumbo la luz roja del espigón de Barbate con velocidad de máquinas 9 nudos (corrección total 4º NW). Nos afecta una corriente de 110º y velocidad 2 nudos. Calcular rumbo de aguja a Barbate.In GPS position l: 36º 00.00' N, L: 005º 50.00' W you head for Barbate breakwater red light at 9 knots engine speed (Ct = 4º NW) in a current setting 110º at 2 knots. Calculate the compass course to Barbate:
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Correct answer: a) 332º
Why it is correct
From 36º 00.0′ N, 005º 50.0′ W to Barbate red light (36º 11.3′ N, 005º 55.3′ W) the effective course is Ref = 339º. Solving the current triangle (Rc = 110º, Ihc = 2 knots, Vm = 9 knots) gives Rv = 328º. With Ct = −4º (4º NW), the compass course is Ra = 328º − (−4º) = 332º.
Why the others are not
- b) Stops at true heading Rv = 328º or subtracts the 4º negative compass error.
- c) Stops at true heading Rv = 328º or subtracts the 4º negative compass error.
- d) Stops at true heading Rv = 328º or subtracts the 4º negative compass error.
How to work it out in the exam
- Plot Ref = 339º to Barbate and counteract the current (110º, 2 kn) with Vm = 9 kn ⇒ Rv = 328º.
- Convert to compass course with Ct = −4º: Ra = 328º + 4º = 332º.
Where this question comes from
- Región de Murcia · 2024 · 3ª convocatoria · PY Tipo 1 · question 36 Official paper · Official answer key
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Pending instructor review. Machine translation, not reviewed.