Hover or tap underlined Spanish terms to see their translation and exam tip.
El 9 de abril de 2016, al encontrarnos en la enfilación de los faros de Punta Alcázar y Punta Cires y al Este verdadero del Faro de Punta Carnero, damos rumbo para pasar a 3 millas del Faro de la Isla de Tarifa, teniendo en cuenta que existe una corriente de Rc = SE e Ihc = 3 millas. Velocidad 8 nudos, declinación magnética de la carta: 05º 00' W 2006 (6' E), desvío de la aguja = ‒8º (menos). Calcular el rumbo de aguja.On 9 April 2016 on the Punta Alcázar–Punta Cires leading line and due East true of Punta Carnero, you head to pass 3 miles off Isla de Tarifa at 8 knots in a current Rc = SE, Ihc = 3 knots (chart dm 05º 00' W 2006 (6' E), dev –8º). Find Ra:
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Correct answer: a) 278º
Why it is correct
The start (Alcázar–Cires alignment due East of Carnero) is 36º 04.3′ N, 005º 19.5′ W. The tangent to pass 3 miles south of Isla de Tarifa is Ref = 247º. With a SE current (135º, 3 knots) and Vb = 8 knots, the current triangle gives Rv = 266º. In 2016 dm = −5º + 1º = −4º; with deviation −8º, Ct = −12º and Ra = 266º + 12º = 278º.
Why the others are not
- b) Does not offset the SE current in the vector triangle or applies Ct = −12º with the wrong sign.
- c) Does not offset the SE current in the vector triangle or applies Ct = −12º with the wrong sign.
- d) Does not offset the SE current in the vector triangle or applies Ct = −12º with the wrong sign.
How to work it out in the exam
- Plot the start and draw the tangent 3′ south of Tarifa (Ref = 247º); with Rc = 135º (3 kn) and Vb = 8 kn find Rv = 266º.
- With Ct = −4º − 8º = −12º, compute Ra = 266º + 12º = 278º.
Where this question comes from
- Junta de Andalucía · 2016 · 1ª convocatoria · PY Módulo de navegación · question 16 Official paper · Official answer key
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Pending instructor review. Machine translation, not reviewed.