Vessel Navigation and Tides
The answer to each question is either A,, C or D. Decide what your answer is then put an X in the appropriate box of the answer grid. There is only one correct answer to each question. Any rough working should be done on the question paper and not on the answer grid.
Q1. The following statements relate to gyro compasses. Choose the one statement that is correct. A. The gyro compass is set to point true north and uses the earth s magnetic field.. Gyro repeaters on bridge wings do not need to be checked against the main gyro after initial start-up. C. A gyro compass will always operate correctly immediately after a power outage. D. Speed and latitude corrections usually need to be applied to the gyro compass. Where the gyro does not have direct log or position input, manual corrections have to be made as required Q2. An azimuth mirror is a device found on a ship that is A. fitted over a compass binnacle to take bearings of various objects.. used to examine the internal working parts of a compass. C. used to reflect light onto a compass card. D. a magnifier for a compass card. Q3. A magnetic compass shows a ship s head to be SSW. Expressed in degrees this heading is A. 192½. 202½ C. 247½ D. 157½
Q4. Magnetic compass errors are due to errors in variation and deviation. Which of the following statement is correct? A. Variation occurs because the earth s magnetic poles are not coincident with the true geographical poles.. Deviation is caused by the fluctuations in the earth s magnetic field. C. Magnetic course is the term given to the true course when both variation and deviation have been applied to it. D. On any one heading deviation is always changing. Q5. A simple and practical method of finding compass error is by transit bearings. Which of the following statements is correct? A. Transits are used in mid ocean. The compass bearing of the transit should be noted five minutes after the objects are aligned. C. Church spires are unsuitable objects to use when obtaining a transit. D. If a vessel is following a channel using leading marks, the compass bearing will be the ship s head, when the bow of the vessel is in line with the leading marks ahead. Q6. A vessel is on passage steering a true course of 061.The gyro error 1 L. The variation is 7 W and the deviation for the ship s head is 4 E. From the following statements, choose the correct answer. A. The gyro heading is 062 (G) and the compass course is 064 (C). The gyro heading is 060 (G) and the compass course is 058 (C) C. The gyro heading is 060 (G) and the compass course is 064 (C) D. The gyro heading is 062 (G) and the compass course is 050 (C)
Q7. The vessel is being steered on autopilot in heavy weather and a compass alarm indicates the vessel is off course. The response to this should be to A. adjust the yaw control on the autopilot until the alarm goes off. make a note of the degree of deviation and inform the Officer of the Watch immediately C. ignore it until the vessel comes back on course D. switch to manual steering Q8. Symbols and abbreviations used on UK admiralty marine navigational charts are published A. on the back of each navigational chart.. in notices to mariners. C. in admiralty chart 5011. D. in admiralty chart 1150. Q9. Map projections are mathematical methods enabling curved surfaces to be displayed on a flat surface, such as a marine navigational chart or land map. The Mercator projection (a cylindrical map projection) is used for many marine navigational charts. A key feature of marine charts based on this projection is that A. course lines have to be drawn in short segments with incremental changes of direction.. lines of direction may be represented as straight lines known as rhumb lines. C. lines of direction may be represented as straight lines known as Mercator lines. D. they should not be used near the equator as they are only suitable for use in high latitudes.
Q10. Passage planning can be done with either paper charts or electronic charts. Electronic charts need to be displayed on an electronic chart display and information system (ECDIS).Which of the following statements is correct? A. Electronic navigational charts (ENC) are unofficial nautical charts.. Raster navigational charts (RNC), when displayed on ECDIS equipment, they are fully equivalent to paper charts. C. Raster charts are exact copies of paper charts and the information in them is intelligent. D. Vector charts are compiled by assigning each and every chart feature a set of values, which is stored in a layered digital database. Q11. Information shown on a marine navigational chart may change over time. Details of updates and corrections to UK admiralty marine navigational charts may be obtained from A. nautical bookshops.. admiralty notices to mariners. C. MCA M notices. D. admiralty notices to ships. Q12. The main causes of tides are the A. gravitational forces of the moon and sun on the earth, and the centrifugal forces of the earth s rotation.. sun spots and electric storms in the earth s atmosphere. C. gravitational forces of the moon and sun, and the magnetic force of the earth. D. magnetic forces of the moon and sun, and the gravitational force of the earth. Q13. The charted depth shown at a location on a navigational chart is the height of water at that location below chart datum. With regards chart datum, choose from the following statements the response that is correct. A. y international agreement chart datum is defined as a level chosen so that the tide will frequently fall below it.. In the UK, chart datum is approximately the level of the Highest Astronomical Tide (HAT). C. The Lowest Astronomical Tide (LAT) is the lowest tide to occur which can be predicted under average meteorological conditions and under any combination of astronomical conditions. D. Chart datum is the extreme low level of tide that can ever be reached.
Q14. The International Association of Lighthouse Authorities (IALA) Maritime uoyage System uses lateral, cardinal and special buoys. From the following statements, select the statement which is correct. A. Lateral buoys indicate the side on which a vessel may safely pass.. Cardinal buoys indicate the location of the safest or deepest water by reference to the cardinal points of the compass. C. Special buoys identify the safest water for the navigation of the vessel. D. For cardinal buoys, the world is divided into two regions X and Y. Q15. The IALA A system of marine navigational buoyage is used in A. Australia. North America. C. South America. D. Japan. Q16. Which of the following characteristics is correct for the buoyage system in Region A? A. Port marks are green and may have a green flashing light of any rhythm.. Starboard marks are square or have a flat top. C. ifurcation marks indicate the preferred and secondary channels. D. A vessel entering a port or river would find the yellow and black marks to starboard. Q17. The general direction of marine navigational buoyage means the direction A. from which a buoyed channel should be approached.. of the main stream or ebb deemed to apply in a particular location. C. of the main stream or flood deemed to apply in any particular location. D. of a straight buoyed channel.
Q18. The key purpose of drawing up a passage plan is A. to keep costs to a minimum.. the safety of navigation. C. to keep fuel consumption to a minimum D. for the welfare of the crew. Q19. Certain nautical publications are required to be carried by UK flagged ships, and others are recommended. From the following list, choose the publication which is considered obligatory. A. The Atlas of World Ports.. The Times Atlas of the Ocean. C. Operating and Maintenance Instructions for Navigational Aids carried by the ship. D. Ocean Passages for the World. Q20. Actual tidal conditions at a location may be different from those predicted. From the following, choose the statement which is correct. A. A prolonged period of high pressure may raise the height of tide by up to 0.3 metres.. A strong onshore wind will lower the sea level at a coastal location. C. Storm surges are caused by earthquakes. D. The result of storm surges is a wave trough that is lower than normal, and a wave crest that is higher than normal
Answer Grid: Vessel Navigation and Tides: A C D 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Candidate s Name Date
ANSWERS Q1 Q2 Q3 Q4 Q5 Q6 Q7 Q8 Q9 Q10 Q11 Q12 Q13 Q14 Q15 Q16 Q17 Q18 Q19 Q20 D A A D C C D A C A C C D