Chart work

Four questions with at most 2 mistakes. It needs practice with a real chart, rulers and dividers.

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Formulas

Compass to true: true = compass + Ct. True to compass: compass = true − Ct. Distance = speed × time.

A minute of latitude is one mile. A minute of longitude is not: multiply by the cosine of latitude. On the chart, measure on the latitude scale.

Activities

• Navigation calculationsTotal correction, courses, departure and dead reckoning, step by step.

Questions in this unit

• We are at a point A at 36º 10'N – 006º 10'W and want to go to another point B at 35º 50'N – 006º 00'W. How long will this run take at a constant speed of 8 knots?
• At 35º 45'N – 006º 15'W, we set course for a point P at 36º 00'N – 006º 00'W at a speed of 10 knots with a total correction for the resulting course of 8º NW. Calculate the compass course to point P:
• At 10:00 by the ship’s clock we are at position A: Latitude 35°45’N / Longitude 006°15’W. From here we set course for position B: Latitude 36°00’N / Longitude 006°00’W. With a local variation of 2°NW and a compass deviation of (-6º). Calculate the compass course.
• Our GPS shows position 36º 00' N – 005º 50'W and we want to go fishing at a point at 36º 05'N – 006º 05'W. We want to do the run in 90 minutes. What speed should we set?...:
• We are at a point A at l = 35º 50'N – L = 006º 10'W and set course for another point B at l = 35º 55'N – L = 005º 55'W. Our speed is 9 knots. Calculate the time to reach point B:
• We keep sailing until we reach position C: Latitude 36º05’N / Longitude 05º57.4’W, and set compass course 110º. Calculate the true course if magnetic variation is 2º(-) and deviation 1º(+).
• At 14:00, at Latitude 35º 50’N and Longitude 006º 10’W, we sail on true course 060º at 6 knots. Calculate the position at 17:00.
• At ship’s clock 08h 00m on 21 November 2020 we are at 36º 05.0' N, 006º 10.0' W. Calculate the position at 10h 30m, given that the boat’s speed is 7.2 knots and the true course is 110º. The total correction is +10º (plus).
• 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).
• At 08h 00m on 25 March 2023 we are at true position 36º 10.0' N, 006º 10.0' W. We sail at 8 knots on compass course 155º, with no wind or current. Calculate the dead reckoning position at 09h 30m, given that magnetic variation is 2° NW and deviation +9° (plus).
• At 14h 30m on 6 April 2024 we are at true position 36º 08.0' N, 006º 13.0' W. We sail at 6 knots on compass course 116°. Calculate the dead reckoning position at 16h 45m, given that compass deviation is –8° (minus) and magnetic variation 5º NW.
• At ship’s clock 10h 00m on 16 November 2024 we are at 35º 50′ N, 006º 08′ W. We sail at 6 knots on compass course 085°. Calculate the dead reckoning position at 12h 30m. Magnetic variation = 4° NW and compass deviation = –8° (minus).
• At ship’s clock 16h 15m on 22 March we are at 36º 00′ N, 006º 00′ W. We sail at 4 knots on compass course 323°. Calculate the dead reckoning position at 18h 30m. Magnetic variation = 2º NW and compass deviation = –6° (minus).
• At 18h 20m on 15 November 2025 we are at true position 36º 00.0' N, 005º 50.0' W. We sail at 6 knots on compass course 311°. Calculate the dead reckoning position at 20h 35m, given that compass deviation is –6° (minus) and magnetic variation 5º NW.
• Sailing on True Course = N, we leave a point at l: 35º 45’ N; L: 005º 14’ W and sail for one hour at 5 knots. Which of these answers is closest to our position?
• Given a departure position l= 35º45'N; L= 005º14' W, ship’s clock 15:00, boat speed 5 knots and compass course 355º. Total correction = +5º. Calculate the dead reckoning position at 16:30.
• From position l=35° 58' N L=005° 59' W we sail on true course 106°, for two hours at 7.2 knots. What will the final position be? (Choose the closest answer)
• A boat is at l=36° - 04.0' N and L=006° - 05.0' W, sailing true north at 12 knots. Calculate the position after 30 minutes on that course and speed.
• We are at 35º 53.0′ N, 006º 02.5′ W and want to sail to 35º 52.0′ N, 005º 36.7′ W. What compass course must we set and what distance will we run, given that deviation is +2º and magnetic variation = 4º NW?
• From known position 39º 20' N, 016º 45' W you sail on compass course Ra = 050º at 15 knots with total compass error CT = –3º 24'. Determine your dead-reckoning position after 10 hours:
• Steering from 35º 50' N, 006º 00' W towards 36º 00' N, 005º 50' W with total compass error Ct = 4º NE, calculate the compass course to steer:
• With a charted true course of 218º, magnetic variation updated to the current year = 10º E, and compass deviation = –6º, what is the compass course?
• At HRB 10:00 from point A (35º 45' N – 006° 15' W) you set course for point B (36º 00' N – 006º 00' W) with variation 2º NW and deviation –6º. Calculate the compass course:
• Steering compass course 340º on the opposition line of Punta Almina and Punta Carnero lighthouses, you take a compass bearing of Punta Carnero = 332º. Calculate the total compass error:
• Crossing the opposition of Isla de Tarifa and Punta Cires lighthouses, you observe Punta Alcázar at true bearing 205º. How far are you from Punta Europa lighthouse?
• Find the coordinates of a vessel located 6 miles from Cape Spartel and 5.5 miles from Punta Malabata:
• At 10:00 ship’s time on the opposition line of Isla de Tarifa and Punta Cires lighthouses, you simultaneously measure a radar distance of 6 miles to Punta Alcázar. What is your position?
• Sailing near Barbate at 09:30 ship’s time, your bow is pointed directly along the leading line (enfilación) of Trafalgar and Cabo Roche lighthouses. What is your true course?
• From position A at Latitude 35º 50' N / Longitude 06º 10' W, you set a true course for the port of Barbate (pier head). What true course must you steer?
• What are the true course and distance from the breakwater head of the port of Cabo Roche to Cape Spartel lighthouse?
• At 11:00 ship’s time you take simultaneous compass bearings Da Punta Europa = 010º and Da Punta Carnero = 320º (dm = 3º NW, Deviation = 4º NE). What is your position at 11:00?
• At 20:00 ship’s time, while on the Punta Europa–Punta Almina opposition line, you take a compass bearing of Punta Europa = 338º. What is the total compass error (Ct)?
• At 19:00 ship’s time in position l = 36º 01.0' N, L = 005º 20.5' W, you set course to pass 2.5 miles off Isla de Tarifa lighthouse (dm = 3º NW, Deviation = 7º NE). Calculate the compass course (Ra):
• Steering true course 105º, you take simultaneous relative bearings of Punta Camarinal = 43º Port and Punta Malabata = 35º Starboard. Calculate your position:
• Sailing at 10 knots on true course 070º across the opposition of Punta Europa and Punta Almina lighthouses, you take a compass bearing of Punta Almina = 156º. Calculate the total compass error:
• Sailing at 8 knots on true course 240º, you simultaneously take relative bearings of Punta Carnero = 60º Starboard and Punta Almina = 80º Port. Calculate your position:
• Crossing the leading line (enfilación) of Cape Spartel and Punta Malabata lighthouses, you observe that alignment at compass bearing 090º. Calculate the total compass error:
• On the leading line of Cape Spartel and Punta Malabata lighthouses at 4 miles from Cape Spartel, you set course to pass 4 miles off Punta Malabata (chart variation 4º E 2006 (6' W), deviation = +5º). What is the compass course?
• At 09:00 ship’s time, steering true course 080º at 8 knots, you take relative bearings of Punta Carnero = 60º Port and Punta Camarinal = 140º Port. Calculate your position:
• 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?
• On 10 March 2018 at 11h 00m in true position 36º 00' N, 005º 50' W, you set course for the port of Tangier (breakwater light) at 4 knots (variation = 3º NW, deviation = +3º). Find the compass course and ETA at Tangier:
• On 21 November 2020, steering compass course 038º (variation 2º NE, deviation +4º), you obtain simultaneous relative bearings of Cape Trafalgar = 89º Port and Punta Paloma = 25º Starboard. What is your position?
• 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:
• Steering Ra = S 76º W (deviation = −5º, variation = 5º NW), you observe simultaneous relative bearings of Punta Europa = 157º Starboard and Punta Almina = 120º Port. What is your position?
• Departing Barbate (red breakwater light Fl.R.4s5M) on true course 175º, after running 12 miles how far are you from Isla de Tarifa?
• Steering true course 130º, you take a relative bearing of Cape Trafalgar lighthouse = 090º Port at a distance of 6.3 miles. Calculate your position:
• Steering compass course 079º (variation 4º NE, deviation +2º), you take relative bearings of Isla de Tarifa = 064º Port and Punta Alcázar = 039º Starboard. Calculate your position:
• Crossing the opposition line of Punta Paloma and Punta Malabata lighthouses, you observe Punta Malabata at compass bearing 180º. Calculate the total compass error:
• On the leading line (enfilación) of Punta Alcázar and Punta Cires lighthouses while steering true course 230º, you observe Punta Cires at compass bearing 220º. Calculate the total compass error:
• At 10h 00m on 25 March 2023, steering true course 340º due South true of Cape Trafalgar with Punta Camarinal bearing 110º Starboard, you set course to pass 5 miles off Cabo Roche (variation 4º NW, deviation +4º). What is the compass course?
• At 10h 00m on 17 June 2023, located due South true of Punta Camarinal and due West true of Isla de Tarifa, you set course for the port of Barbate (shore light) with variation 6º NE and deviation +4º. What is the compass course?
• At 08:00 ship’s time on 13 July 2024, 5 miles NW true of Punta Malabata, you set course at 8 knots for a point 4 miles South true of Cape Trafalgar (variation 3º NW, deviation +6º). Find the compass course and ETA:
• At 09h 20m on 22 March 2025, located due West true of Isla de Tarifa and SW true of Punta Paloma, you set course for Barbate (shore light) at 4.5 knots without wind or current (chart variation 4º 06' E 2014 (6' W), deviation +10º). Find Ra and ETA:
• On 5 July 2025 you observe Punta Almina lighthouse at true bearing 154º and distance 6 miles. What is your position?
• From position 36º 06.6' N, 006º 02.2' W you set course for Punta Malabata lighthouse with total compass error Ct = –6.5º. What is the compass course (Ra)?
• On 13 June 2026 at 12h 00m, 5 miles due West of Cabo Roche lighthouse, you steer Ra = 154º at 6 knots (chart variation 5º 20' W 2010 (5' E), deviation −10º). What are the true bearing and distance from Cape Trafalgar at 13h 42m?
• Located 3 miles due North true of Cabo Negro lighthouse (south of Ceuta), calculate the compass course to a point 5 miles NE true of Punta Almina lighthouse (deviation = +5º, variation = 3º NE):
• On 16 October 2021 at 13:12 on true course 295º in the Isla Tarifa–Punta Malabata opposition, you take a 025º Starboard relative bearing and 320º compass bearing to Punta Camarinal. Find your compass course and position:
• On 18 April 2026 at 12:30 ship’s time, while on the Punta Europa–Punta Almina opposition line, you observe a radar distance of 5 miles to Punta Carnero. Determine your true position:
• At 13:00, 3 miles NW true of Cape Spartel, you head for Punta de Gracia at 5 knots. After 5 miles you alter to Ra = 086º (deviation +1º, variation 3º E) at 5 knots. What is your position at 17:00?
• Sailing East of the meridian of Isla de Tarifa, you simultaneously measure radar distances of 5 miles to Isla de Tarifa lighthouse and 6.8 miles to Punta Cires lighthouse. Find your position:
• At 10:30 on the Punta Malabata–Tangier breakwater leading line at 5 miles from Malabata, you steer Ra = 068º (Ct = +2º) at 10 knots for 1.5 h, then head for Ceuta red entrance light. Find your DR position at 12:15:
• At 09:30 from Barbate pier head at 6 knots you steer Ra = 219º (Ct = –3º) to the Trafalgar–Camarinal opposition, then towards 11.2' NNW of Malabata (Ct = +1º) until West of Tarifa, then to Tangier (Ct = +2º). Find final Ra and ETA:
• A vessel on the opposition line of Cape Trafalgar and Cape Spartel lighthouses observes Cape Trafalgar at compass bearing 342º. Find the total compass error:
• At 15:00 on Ra = 120º (deviation +2º, variation 1º W), you take bearings Da Trafalgar = 045º and Da Camarinal = 090º, then head for Punta Malabata at 10 knots. Find your position and time when due North true of Cape Spartel:
• At 09:00 due South of Isla Tarifa with Da Punta Alcázar = 109º (deviation +3º, variation 2º W), you head for 2' N of Punta Cires at 6 knots until Da Carnero = 270º and Da Europa = 295º (deviation +2º), then head for Sotogrande breakwater. Find your 13:00 position:
• While on the Isla Tarifa–Punta Alcázar opposition line, you simultaneously take compass bearings Da Isla Tarifa = 344º and Da Punta Cires = 117.5º. Calculate your true position:
• At 11:30 on Ra = 220º (deviation –3º, variation 5º E), you take bearings Da Punta Europa = 280º and Da Punta Almina = 201º, then head for Isla de Tarifa (deviation –4º) at 7.5 knots. Find Ra and the time when due North true of Punta Cires:
• With the echo sounder reading 50 metres at 20:00 ship’s time, you take a compass bearing of Cape Trafalgar lighthouse = 005º (total compass error Ct = 5º NW). Find your observed position:
• At 09:15 you fix your position with Da Punta Malabata = 161º and Da Punta Cires = 089º (deviation –3º, variation 1º W), then head for a point 3 miles NW true of Cape Spartel (new deviation –2º). What is the compass course?
• At 09:30 on Ra = 238º (Ct = –3º) due South of Punta Paloma with Punta Cires bearing 126º Port, you head at 5 knots towards the midpoint of the Spartel–Trafalgar opposition (Ct = +1º) until 12:00, then head for 3' SSW of Trafalgar (Ct = +2º). Find final Ra and ETA:
• At 12:00 on Ra = 095º (deviation –3º, variation 2º W) on the Punta Paloma–Punta Malabata opposition, you take a 30º Starboard relative bearing to Punta Alcázar, then head for 4 miles North true of Cape Spartel (new deviation –3.5º). Find Ra:
• At 10:30 on the Punta Paloma–Isla Tarifa leading line, you observe Da Punta Alcázar = 184º, then steer Ra = 267º at 7 knots (deviation –1.5º, variation 2.5º W). What is your estimated position at 12:00?
• At 12:30 you fix your position with Da Isla de Tarifa = 026.5º and Da Punta Camarinal = 304.5º (deviation +2º, variation 0.5º W), then head for 8 miles East of Punta Europa (new deviation –1º) at 7 knots. Find Ra and ETA:
• On the leading line (enfilación) of Cape Trafalgar lighthouse and Cerro del Puerco, you observe Punta de Gracia lighthouse at compass bearing N89ºE (variation 1º W, deviation 2º E). Find your true position:
• At 10:00, 3 miles South true of the CEPSA refinery pier light in San Roque, you head for Ceuta green breakwater light at 6 knots. On reaching the Punta Carnero–Punta Europa opposition you turn to Ra = 205º (deviation +2º, variation 3º E). Find your 11:30 position:
• While on the leading line (enfilación) of Punta Carnero and Punta Europa lighthouses, you take compass bearings Da Punta Europa = 240º and Da Punta Carbonera = 322º. What is your position?
• At 09:30 you fix your position with Da Isla de Tarifa = 095º and Da Punta Malabata = 178º (Ct = +2º), then head at 6 knots for a point bearing 207º true at 2.8 miles from Cape Trafalgar (new Ct = –4º). Find Ra and ETA:
• At 09:30 in 35º 47.0' N, 006º 12.0' W you head at 6 knots towards point P (35º 58.0' N, 005º 55.0' W) with deviation –3º and variation 3º W. When Cape Spartel bears 116º compass, you turn to pass 3 miles North true of Punta Malabata. Find your 12:30 position:
• Near the Strait of Gibraltar TSS, you are 10 miles from Punta Almina lighthouse and 5 miles south-west of Punta Europa lighthouse. Determine your position:
• At 08:00, 5 miles West true of Cape Spartel, you steer Ra = 051º (deviation –3º, variation 3º W) at 6 knots until 09:00, then head for point P (36º 08' N, 005º 53' W) with new deviation +1º. Find Ra to P and the time when Punta de Gracia is abeam to starboard:
• Steering compass course 297º (variation 4º W, deviation –2º), you simultaneously take relative bearings of 275º to Cape Spartel lighthouse and 189º to Punta Malabata lighthouse. What is your position?
• On 29 June 2024 at 10:35, you fix your position with Da Cabo Roche = 011.5º and Da Cabo Trafalgar = 085.5º (deviation –1.9º throughout). Find the compass course and ETA at 6 knots to a point 3 miles due South of Barbate pier red light:
• On 29 June at 11:30 on Ra = 208º (Ct = +2º) along the Punta Europa–Punta Almina opposition with M = 88º Starboard to Punta Carnero, you alter to Ra = 253º (Ct = +1º) at 8 knots. Find your DR position at 13:00:
• Plot the point with coordinates 36º 07.3' N and 005º 45.8' W on the Strait of Gibraltar chart and state what feature it represents:
• At 10:00 you take bearings Da Cape Trafalgar = 327º and Da Barbate = 033º (deviation –1º, variation –4º), then head at 10 knots to pass 3 miles off Punta Paloma. Find your time when abeam of Punta Gracia (Torre de Gracia):
• At 11:00 ship’s time you simultaneously obtain compass bearings Da = 318º to Isla de Tarifa lighthouse and Da = 022º to Punta Carnero lighthouse with total compass error CT = –6º. Find your position:
• What is the exact charted distance in nautical miles between Cape Trafalgar lighthouse and Punta Cires lighthouse?
• Calculate the true position of a vessel located inside the precautionary area of the Strait of Gibraltar TSS at 8 miles from Punta Almina lighthouse and 7 miles from Punta Europa lighthouse:
• On 16 October 2010 at 11:06 on Ra = 010º at true position 35º 59' N, 005º 14' W, calculate your DR position at 12:12 at 12 knots with compass deviation 3.5º NE:
• Steering true course 312º on the Punta Malabata–Isla de Tarifa opposition line, you take a 25º Starboard relative bearing and 344º compass bearing to Punta Paloma lighthouse. Find your compass course and position:
• Sailing through the Strait of Gibraltar, you measure radar distances of 5 miles to Isla de Tarifa lighthouse and 3 miles to Punta Paloma lighthouse. Find your position:
• A vessel on the opposition line between the North cardinal mark off Punta Malabata and Punta de Gracia lighthouse observes that cardinal mark at compass bearing 176°. Find the total compass error:
• On the opposition line of Cape Trafalgar and Punta de Gracia lighthouses, you simultaneously take compass bearings Da Cape Trafalgar = 290º and Da Barbate = 353º. What is your position?
• At 10:22 on Ra = 140° (variation –5°, deviation +4°), you take Da Cape Trafalgar = 030º and M = 45º Port to Punta Camarinal, then head for Tangier breakwater light at 12 knots. Find your position at 11:43:
• Find the true position of a vessel on the opposition line of Punta Almina and Cabo Negro lighthouses at a distance of 4.8 miles from Cabo Negro:
• Sailing along the Punta Carnero–Punta Europa leading line, you fix your position when Punta Almina bears due South true, then set course to pass 2 miles abeam to starboard of Punta Carnero (Ct = +5º). Find your start position and compass course:
• At 10:45 steering Ra = 281º (variation 4º W, deviation +1º), you simultaneously take relative bearings of 65º Starboard to Punta Paloma lighthouse and 157º Starboard to Isla de Tarifa lighthouse. What is your position?
• Simultaneously observing true bearings Dv Cape Spartel = 216º and Dv Punta Malabata = 115º, you set course to pass 3 miles off Punta Cires. Where will you be after running 13 miles?
• What is the position of our vessel when located 5 miles from Punta Paloma lighthouse with Punta Paloma bearing 020º true?
• While underway you simultaneously take compass bearings Da = 315° to Cape Trafalgar lighthouse and Da = 070° to Isla de Tarifa lighthouse (deviation +1°, variation 1° W). Find your position:
• At 17:00 Hrb steering true course 270°, you simultaneously take compass bearings Da Cape Spartel = 230° and Da Punta Malabata = 140° with total compass error Ct = –5º. Determine your position:
• At 12:00 on Ra = 275º (deviation +2º, variation 5º W) on the Punta Paloma–Punta Malabata opposition with Da Punta de Gracia = 337º, you head for Cape Trafalgar (new deviation +4º) at 8 knots. Find Ra and the time when abeam of Barbate light:
• What is the charted distance between Punta Leona and Punta Kalúli (or Sainar) on the Moroccan coast?
• On the leading line of Cape Trafalgar and Cabo Roche lighthouses at 7 miles from Trafalgar, you head for Barbate port (red light at the end of the breakwater). What speed is needed to make the run in 1 hour?
• Positioned on the opposition line of Punta Europa and Punta Almina lighthouses, you measure a distance of 6 miles to Punta Carnero lighthouse. What is your position?
• Departing Barbate port (from the entrance red light) on compass course Ra = 150º at 7 knots (variation 2º NW, deviation +2º), how far will you be from Punta de Gracia lighthouse 1 hour later?
• On the leading line of Punta Cires and Punta Alcázar lighthouses with Punta Carnero bearing due North true, you set course for Ceuta port (green entrance light) at 8 knots. How long will it take to reach Ceuta?
• Departing Tangier port (breakwater end light) bound for Barbate port (red light at the end of the breakwater), what speed must you set to complete the passage in 3 hours?
• Positioned at 36º 00' N, 005º 50' W, calculate how many minutes it will take to reach Barbate port (red light at the end of the breakwater) at a speed of 14 knots:
• On the opposition line of Punta Malabata and Punta de Gracia lighthouses at 6 miles from Punta Paloma lighthouse, you set course for Tangier (breakwater end light) with Ct = 6º W. Calculate the compass course:
• At HRB = 1030 you are positioned 5 miles due East true of Punta Europa lighthouse. Calculate your arrival time (HRB) at Ceuta port at a speed of 9 knots:
• Positioned 3 miles due South true of Punta Europa lighthouse, you set course to pass 1 mile due South true of Isla de Tarifa lighthouse (variation 2º W, deviation –3º). Calculate the compass course:
• From charted position 36º 00' N – 005º 55' W you set course for Tangier port (breakwater end light) at 10 knots with total compass error Ct = 5º NE. Calculate the compass course (Ra):
• Located on the opposition line of Punta Alcázar and Isla de Tarifa lighthouses at a distance of 7 miles from Punta Cires lighthouse, what is your latitude?
• From position 35º 58' N – 005º 50' W you sail to Barbate port (entering by the red light at the end of the breakwater) in 1.5 hours. What speed must you maintain?
• Sailing right on the opposition line of Punta Almina and Punta Europa lighthouses, your radar shows a distance of 6 miles to Punta Carnero lighthouse. Indicate your position:
• At HRB = 1230 Punta Europa lighthouse bears 290º true at a radar distance of 9 miles. What is your position?
• At 1130 ship’s time you simultaneously observe true bearings Dv Cape Trafalgar = 000º and Dv Punta de Gracia = 090º. How far away is Barbate port (breakwater red light)?
• Departing Tangier port bound for a charted point 10' due North true of Cape Spartel at a speed of 7 knots, how long will the run take?
• Leaving Barbate port at HRB = 1000 on compass course Ra = 220º (variation 2º W, deviation +2º) at 8 knots, how far will you be from Cape Trafalgar lighthouse at HRB = 1130?
• Departing Ceuta port bound for Algeciras port (red light at the end of the breakwater) with total compass error Ct = 5º W, what compass course must you steer?
• At HRB 0900 you leave Ceuta port (green entrance light) and set a direct true course towards Algeciras port (red breakwater light). What true course have you set?
• From position A (36º 00' N, 005º 20' W) you head for position B (located 5 miles from Punta Cires and 5 miles from Isla de Tarifa lighthouse) at 10 knots. How long will it take to reach B?
• After clearing the traffic separation scheme, you take simultaneous true bearings Dv Punta Paloma = 055º and Dv Punta Malabata = 159º. What is your position?
• Positioned on the line joining Punta Cires and Isla de Tarifa lighthouse at 5 miles from Punta Cires, you steer true course 270º until due North of Tangier. What is your final position?
• Positioned at the entrance of Algeciras port (red breakwater light), how long will it take to reach Ceuta (green entrance light) at a speed of 12 knots?
• After a current sets you eastward, you fix your position with simultaneous true bearings Dv Punta Paloma = 067º and Dv Punta Malabata = 143º. What is your position?
• Due South of Punta Paloma at 5 miles from Punta Malabata, you head for a point 3 miles due North of Punta Cires (variation –2º, deviation –1º). What compass course must you steer?
• At Hrb 10h 25m you depart Ceuta port (green entrance light) heading directly for Punta Europa at a speed of 12 knots. How long will it take to reach Punta Europa?
• From point A on the chart at 36º 00' N – 005º 50' W, you head for Barbate port (red light at the end of the breakwater) at 10 knots. How long will the run take?
• Positioned 3 miles due North true of Punta Almina lighthouse, you set course for the red light at the end of Algeciras port breakwater at 11 knots. What is your true course?
• While due East of Punta Europa lighthouse, you take a compass bearing of 187º to Punta Almina lighthouse (variation 2º NW, deviation –5º). What is your position?
• Positioned 10 miles from Cape Trafalgar lighthouse and 8 miles from Punta de Gracia lighthouse, what is the compass course to Barbate port (red breakwater light) with Ct = 5º NE?
• With Cape Spartel lighthouse 4' due South true of you, you head for point P located 4' due North true of Punta Alcázar lighthouse at 7 knots. How long will it take to reach P?
• Positioned due South true of Punta Paloma lighthouse at 5' from Punta Malabata lighthouse, you set course for 3' due North of Punta Cires lighthouse (Ct = –3º). Calculate the compass course:
• Leaving Ceuta port (red light on the east breakwater) at a log speed of 9 knots, calculate how long it will take to reach Algeciras port (breakwater end light):
• Calculate the speed required to make the passage from Barbate port (breakwater end light) to Tangier port (breakwater end light) in 2h 30m:
• At HRB 08:30 on compass course Ra = 096º with total compass error Ct = 6º NW, Punta de Gracia lighthouse is dead ahead and Cape Trafalgar lighthouse is abeam to port. Find your position:
• A vessel wants to sail from point A (35° 53.4' N, 006° 10.0' W) to point B located 10 miles due North true of Punta Malabata lighthouse (variation 2º NW, deviation 12º NW). What compass course must it steer?
• On the leading line of Isla de Tarifa and Punta Paloma lighthouses with Punta Alcázar lighthouse bearing due South true, how far away is Punta Carnero lighthouse?
• On the leading line of Punta Paloma and Isla de Tarifa lighthouses at 5 miles from Punta Cires, you steer true course 260º at 15 knots. What is your position after 1.5 hours?
• Steering compass course 120º (deviation 2º NW, variation 3º NW), you take relative bearings 108º Port to Punta Paloma and 5º Starboard to Punta Alcázar. How far is the vessel from Punta Malabata?
• At 6 miles from Barbate main light on the Trafalgar–Punta de Gracia opposition (point A), what true course is required to reach point B at 35° 55' N – 06° 10' W?
• With Punta de Gracia dead ahead and Trafalgar abeam to port at 08:30 while steering Ra = 096º (Ct = 6° NW), what is your charted position?
• At HRB 10h 55m on the line joining Cape Spartel and Cape Trafalgar at 10 miles from Barbate pier head, you head for Tangier port at 12 knots. At what time will you arrive?
• Pointing your bow directly at Punta Europa lighthouse while on the Punta Europa–Punta Almina opposition line, what is your true course?
• At HRB = 1030 you simultaneously take true bearings Dv Punta Carnero = 316º and Dv Punta Cires = 233º. What is your position at that instant?
• To complete the Tangier–Barbate passage (between their respective breakwater ends) in 2.5 hours, what speed must you set?
• Calculate the compass course (Ra) to steer when departing Isla de Tarifa towards Punta Cires, given a total compass error of CT = –5º:
• At HRB = 12-00 steering Ra = 072º (variation 3º NW, deviation 8º NE), Cape Spartel lighthouse bears 70º Starboard relative at a distance of 5 miles. Find your position:
• At the instant the vessel is on the Punta Europa–Punta Carnero opposition line, you observe a compass bearing to Punta Europa of Da = 060º. Calculate the total compass error (CT):
• A ship steering Ra = 117º takes a compass bearing of Tarifa Da = 025º and a relative bearing of Punta Alcázar = 035º Starboard (variation 2º NW, deviation –2º). Calculate its position:
• From position l = 35º 50' N and L = 006º 10' W you sail on true course Rv = 032º at a speed of 6 knots. How far from Punta de Gracia will you be after 2.5 hours?
• On 16 November 2024 at 11:00 on the Punta Carnero–Punta Europa opposition at 2.4 miles from Punta Carnero, find the compass course to Ceuta (green entrance light) given chart variation 3° 00' E 2014 (6' W) and deviation +9°:
• Aboard a vessel on the opposition line of Cape Trafalgar and Punta de Gracia lighthouses, you obtain compass bearings Da Cape Trafalgar = 290° and Da Barbate lighthouse = 350°. Find your true position:
• At 13:00 on compass course 081º (Ct = –4º), you take a relative bearing of 004º Starboard to Punta Cires lighthouse just as Isla de Tarifa lighthouse is abeam. Find your true position:
• From the red entrance light of Ceuta port, you set course to pass 5.2 miles East of Punta Europa lighthouse (leaving it to westward) in 2008 with deviation 1.5º E. Find the compass course:
• At 2.2 nautical miles from Tangier port breakwater lighthouse on the 50-metre depth contour inside the white sector of El Xarf light, what is your true position?
• Steering true course S 32 E, you simultaneously obtain relative bearings of 30º Port to Punta Alcázar lighthouse and 65º Starboard to Punta Malabata lighthouse. What is your position?
• Sailing directly from Punta Tarifa lighthouse towards Punta Cires lighthouse with magnetic variation 4º NW and deviation 3º W, what compass course are you steering?
• A vessel on the leading line of Cabo Roche lighthouse and Cape Trafalgar lighthouse observes Cape Trafalgar lighthouse at a compass bearing of 323º. Calculate the total compass error (Ct):
• From the special mark East of La Línea de la Concepción in 2021, calculate the compass course (Ra) to pass 4.2 miles off Punta Almina lighthouse with compass deviation 3.5º E:
• Inside the prohibited fishing zone at 3.5 miles from Punta de Gracia lighthouse and on true bearing 084º to Punta Paloma lighthouse, what is your true position?
• From a point 5 miles on true bearing 350º from Punta Malabata lighthouse, you sail at 16h 18m on true course 307º at 12 knots. Calculate your DR position at 17h 08m:
• At Hrb 12:00, located West of Cape Spartel at a distance of 5 miles from Cape Spartel with Punta Malabata bearing Dv = 094º, what is your position?
• What is the distance (d) between position A (l = 36º 20.0'N L = 006º 19.0'W) and position B (l = 36º 20.0'N L = 006º 10.0'W)?
• Sailing in an area with magnetic variation (dm) of 2° W and compass deviation of 4° E, a compass bearing (Da) of 343° is taken of a known point on the coast. Calculate the true bearing.
• We are at Latitude 36°00.0'N, Longitude 005°50.0'W, and want to go to Latitude 35°50.0'N, Longitude 006°10.0'W. What true course must we steer?
• At ship's time 14-00 at l = 35º 50'N L = 006º 10'W we sail on true course 060º at speed 6 knots. Position at ship's time 17-00
• At l = 35º 50'N and L = 006º 00'W we head for l = 35º 57'N and L = 005º 28'W, dm = 3º NW and Deviation = 3º NW. Find the compass course (Ra).
• At ship's time 16-20 at l = 35º 56.5'N, L = 005º 17.0'W we head for a point at l = 36º 16.0'N, L = 005º 12.0'W, dm = 3º NW, Deviation = 5º NW. Calculate the Ra.
• At ship's time 13-10 at l = 35º-53.0'N, L = 005º-46.0'W we steer Ra = 084º, dm = 3º NW, Deviation = 3º NW, speed 7 knots. Calculate the estimated position at ship's time 15-30.