KJ

Entrance Examination – Deck Cadet (Navigation - Vocabulary Flashcards)

Deck Cadet Entrance Exam - Navigation Notes (Comprehensive)

  • Q1. Variation definition

    • Question: What is the correct definition of "variation" in navigation?
    • Answer: B
    • Definition: Variation is the angular difference between true north and magnetic north. It is a geographic phenomenon, fixed for a given location on the Earth.
    • Related concepts: Deviation (error induced by the vessel’s own magnetic field) is a separate effect from variation.

  • Q2. Rhumb line

    • Question: What is a rhumb line?
    • Answer: B
    • Definition: A rhumb line is a line crossing all meridians at the same angle. It is a path of constant compass bearing.
    • Contrast: The shortest path on a sphere is a great circle, not a rhumb line.

  • Q3. Ship’s pointing direction term

    • Question: The direction in which a ship is pointing is called:
    • Answer: B (Heading)
    • Terms:
    • Course: intended path over ground that may differ from the ship’s heading.
    • Bearing: direction from one point to another.
    • Track: actual path over the ground.

  • Q4. Difference between course over ground and heading

    • Question: The difference between course over ground and heading is caused by:
    • Answer: C
    • Explanation: Set and drift (wind and current effects) cause the ship’s heading to differ from its course over ground.

  • Q5. Fixing a vessel’s position

    • Question: A vessel’s position can be fixed using:
    • Answer: D
    • Explanation: Two or more position lines (e.g., from radar, bearings, or electronic fixes) are typically needed for an accurate fix.

  • Q6. Chart contents – not part of a nautical chart

    • Question: Which of the following is not part of a nautical chart?
    • Answer: B (Wind speed)
    • Chart components typically include soundings, depth contours, buoy symbols; wind speed is not a standard chart element.

  • Q7. DR in navigation

    • Question: What does "DR" stand for in navigation?
    • Answer: B (Dead Reckoning)
    • DR: position estimation based on last known position, speed, heading, and time, without external fixes.

  • Q8. LOP meaning

    • Question: The term "LOP" refers to:
    • Answer: C (Line of Position)
    • LOP: a line on which the vessel’s position lies, derived from a navigational measurement.

  • Q9. Chart projection commonly used

    • Question: What chart projection is most commonly used in navigation?
    • Answer: C (Mercator)
    • Note: Mercator projection preserves bearings as straight lines, useful for plotting courses.

  • Q10. Definition of a fix

    • Question: A "fix" is defined as:
    • Answer: C (Actual position determined by observations)
    • Methods: bearings, ranges, celestial observations, radar, GPS, etc.

  • Q11. Transit bearing use

    • Question: A transit bearing is best used for:
    • Answer: A (Checking compass error)
    • Application: comparing two lines-of-sight to verify alignment and calibrate instruments.

  • Q12. Nautical mile unit

    • Question: What is the unit of measurement for a nautical mile?
    • Answer: B (1852 meters)
    • Note: 1 NM = 1852 m exactly by definition; also equals 1 minute of latitude along a meridian.
    • Related: 1 degree of latitude = 60 NM; 1 NM ≈ 1.15078 statute miles.
    • Formula: 1\ \text{NM} = 1852\ \text{m}

  • Q13. Definition of Set

    • Question: "Set" is defined as:
    • Answer: C (The direction toward which current flows)
    • Drift concept: Set is the direction of current; drift is the lateral movement caused by current and wind.

  • Q14. Safe water mark meaning

    • Question: A safe water mark indicates:
    • Answer: D (Navigable water all around)
    • Use: marks the entrance to a safe channel; not indicating isolated danger.

  • Q15. Depth measurement at sea

    • Question: What is used to determine depth at sea?
    • Answer: C (Echo sounder)
    • Principle: emits sound waves and measures return time to determine depth.

  • Q16. Distance for 1° of latitude

    • Question: What is the total distance between two waypoints 1° apart in latitude?
    • Answer: B (60 NM)
    • Explanation: Latitude degrees are arc distances on a great circle; 1° of latitude equals 60 nautical miles.
    • Formula: \Delta s = 60\ \text{NM} \quad \text{per} \quad 1^{\circ}.

  • Q17. Latitude after moving north

    • Question: A ship at Lat 10°N, Long 120°E sails 120 NM north. What is the new latitude?
    • Answer: B (12°N)
    • Calculation: \Delta\text{lat} = \frac{120\ \text{NM}}{60\ \text{NM/degree}} = 2^{\circ}; new latitude = 10^{\circ}N + 2^{\circ} = 12^{\circ}N.

  • Q18. Deviation effect on compass reading

    • Question: What is the effect of deviation on compass reading?
    • Answer: B (Varies with heading)
    • Note: Deviation changes with ship’s heading due to the ship’s magnetic influences.

  • Q19. True wind speed from apparent wind

    • Question: A wind reading in the anemometer is 15 knots dead ahead. The ship is heading North at a ground speed of 15 knots. What is the true wind speed?
    • Answer: B (15 knots)
    • Concept: Apparent wind depends on true wind plus the wind generated by the ship’s motion; with the given data, the observed wind is 15 knots ahead, taken as true wind speed in this scenario.
    • Practical note: In real navigation, true wind may differ depending on wind direction and ship course; vector addition applies.

  • Q20. Distance covered in time at constant speed

    • Question: A ship traveling at 15 knots will cover how many nautical miles in 4 hours?
    • Answer: B (60 NM)
    • Formula: \text{Distance} = \text{Speed} \times \text{Time} = 15\ \text{kn} \times 4\ \text{h} = 60\ \text{NM}

  • Q21. ETA calculation example

    • Question: A ship departs at 0830 and will travel 100 NM at 12 knots. What is the ETA?
    • Answer: A (1650)
    • Calculation: Time to cover = \frac{100\ \text{NM}}{12\ \text{kn}} \approx 8.33\ \text{h} = 8\text{ h }20\text{ m}; 0830 + 8:20 = 1650.

  • Q22. Steaming time for given distance

    • Question: Vessel speed is 18 knots. Distance to port: 270 NM. What is the steaming time?
    • Answer: C (15 h)
    • Calculation: t = \frac{270\ \text{NM}}{18\ \text{kn}} = 15\ \text{h}.

  • Q23. Speed increase effect on arrival time

    • Question: A ship is making 10 knots. If you increase the speed by 2 knots, how many hours earlier will it arrive after 240 NM?
    • Answer: C (4 hours)
    • Calculation:
    • Original time: t_1 = \frac{240}{10} = 24\ \text{h}
    • New time: t_2 = \frac{240}{12} = 20\ \text{h}
    • Difference: 24-20 = 4\ \text{h}.

  • Q24. Compass error determination

    • Question: Compass error is determined by:
    • Answer: C (True - Compass)
    • Concept: Compass error = deviation + variation? In this question framed as True minus Compass reading (i.e., True direction minus observed compass direction).

  • Q25. Compass course with variation and deviation

    • Question: A ship is on course 090°, variation 3°E, deviation 2°W. What is the compass course?
    • Answer: B (089°)
    • Calculation: Compass course = True course + (Variation) − (Deviation) = 090° + 3°E − 2°W = 089°.

  • Q26. Wheel over point

    • Question: What is meant by "wheel over point"?
    • Answer: B (Position to apply rudder for a turn)
    • Concept: The rudder angle and position at which to begin a turning maneuver.

  • Q27. Parallel indexing usefulness

    • Question: When is parallel indexing most useful?
    • Answer: B (During arrival in port)
    • Context: A navigation method to monitor position against a planned course during arrivals and stealthy checks.

  • Q28. Primary purpose of a passage plan

    • Question: The primary purpose of a passage plan is to:
    • Answer: C (Navigate safely from berth to berth)
    • Emphasis: Safety, risk assessment, and collision avoidance.

  • Q29. Phase including ENC coverage and navigational warnings

    • Question: Which phase includes checking ENC coverage and navigational warnings?
    • Answer: A (Appraisal)
    • ENC: Electronic Navigational Chart coverage checks are part of early planning and appraisal.

  • Q30. Required speed to reach waypoint on time

    • Question: A ship must arrive at a waypoint 120 NM away by 1800. Present time is 0900. What speed is required?
    • Answer: D (14 knots)
    • Calculation: Time window = 9 hours; required speed = 120 / 9 ≈ 13.33 kn; nearest option is 14 kn.

  • Q31. Barometer reading

    • Question: A barometer measures:
    • Answer: B (Atmospheric pressure)
    • Note: Changes in atmospheric pressure relate to weather patterns.

  • Q32. Cloud associated with thunderstorms

    • Question: What type of cloud is associated with thunderstorms?
    • Answer: B (Cumulonimbus)

  • Q33. Sea breeze and land thermals

    • Question: Wind flowing from sea to land during the day is called:
    • Answer: C (Sea breeze)

  • Q34. Falling barometer indicates weather

    • Question: What does a falling barometer usually indicate?
    • Answer: C (Approaching bad weather)

  • Q35. Beaufort Scale measures

    • Question: The Beaufort Scale measures:
    • Answer: C (Wind force)

  • Q36. Northwest Pacific cyclone name

    • Question: A tropical cyclone in the Northwest Pacific is called:
    • Answer: C (Typhoon)

  • Q37. Fog formation condition

    • Question: Fog is most likely to form when:
    • Answer: C (Temperature and dew point are close)

  • Q38. Instrument measuring humidity

    • Question: Which instrument measures humidity?
    • Answer: A (Hygrometer)

  • Q39. Weather chart color for low pressure

    • Question: What color is used in weather charts to show areas of low pressure?
    • Answer: B (Blue)

  • Q40. Boundary between air masses

    • Question: What is the term for the boundary between two air masses?
    • Answer: C (Front)

  • Q41. Hull length definitions

    • Question: The length between forward and aft perpendiculars is called:
    • Answer: C (LOP - Length between perpendiculars)

  • Q42. Mooring line stop on bitts

    • Question: Which rope is used to stop mooring lines from slipping on bitts?
    • Answer: C (Stopper)

  • Q43. Free surface effect on stability

    • Question: What is the effect of free surface on stability?
    • Answer: B (Decreases GM)
    • Concept: Free-surface liquid in tanks reduces the metacentric height and stability.

  • Q44. Righting lever terminology

    • Question: The angle at which a vessel returns upright is called:
    • Answer: C (Righting lever) [GZ]
    • Concept: GZ is the righting arm; its magnitude depends on heel angle and GM.

  • Q45. Vertical distance keel to waterline

    • Question: What is the name of the vertical distance from keel to waterline?
    • Answer: B (Draft)
    • Note: Draft is the depth of the ship below the waterline; freeboard is above waterline.

  • Q46. Spring line purpose

    • Question: The term "spring line" refers to:
    • Answer: B (Mooring line that prevents forward or aft movement)

  • Q47. Purpose of bilge pumps

    • Question: What is the purpose of bilge pumps?
    • Answer: D (To remove accumulated water from bilge)

  • Q48. GM in stability

    • Question: What does GM stand for in stability?
    • Answer: D (Distance between G and M)
    • Concept: GM is the metacentric height; larger GM generally indicates greater initial stability.

  • Q49. Causes of squat

    • Question: What causes squat?
    • Answer: B (High speed in shallow water)
    • Effect: Increased trim and reduced initial stability due to flow around hull in shallow water.

  • Q50. Rolling period as stability indicator

    • Question: A rolling period of more than 20 seconds means the vessel is:
    • Answer: B (Tender)
    • Interpretation: Tender vessels have longer rolling periods and lower freq of oscillation.

  • Q51. Knots for joining different rope sizes

    • Question: Which knot is used for joining two ropes of different sizes?
    • Answer: C (Sheet bend)

  • Q52. Ballasting risk

    • Question: When ballasting, what must be avoided?
    • Answer: B (Free surface effect)

  • Q53. Lightship meaning

    • Question: The weight of the vessel without cargo, fuel, crew, etc., is called:
    • Answer: C (Lightship)
    • Distinctions: Displacement includes cargo/fuel; Lightship is the weight of the empty ship.

  • Q54. Purpose of a sea anchor

    • Question: The function of a sea anchor is to:
    • Answer: B (Reduce drifting in heavy weather)

  • Q55. Item for controlling roll (stability)

    • Question: Which item helps control roll motions at sea?
    • Answer: A (Bilge keel)

  • Q56. Trim terminology (incomplete item in transcript)

    • Question: Likely about trim indicator (head vs stern).
    • Answer (given): B (1.0 m by the stern)
    • Note: This reflects a trim specification: trim by the stern implies more waterplane depth toward stern by 1.0 m.

  • Q57. Deadweight calculation

    • Question: Displacement is 15,000 tons, lightship is 5,000 tons. What is the deadweight?
    • Answer: A (10,000 tons)
    • Calculation: Deadweight = Displacement − Lightship = 15000 − 5000 = 10000 t.

  • Q58. GM very small implies stability

    • Question: If GM is very small, the vessel is:
    • Answer: B (Tender)
    • Insight: Small GM means less initial stability; vessel tips easier.

  • Q59. Purpose of a load line

    • Question: What is the purpose of a load line?
    • Answer: C (Show maximum legal draft)
    • Usage: Load line marks indicate the legal limits for loading the ship.

  • Q60. Air draft calculation

    • Question: What is the air draft of a ship if masthead is 35 m above keel and draft is 8 m?
    • Answer: A (27 m)
    • Calculation: Air draft = Masthead height above keel − Draft = 35 − 8 = 27 m.

  • Q61. Trim and mean draft from forward/aft drafts

    • Question: A ship has drafts of 8.4 m (F) and 8.6 m (A). What is the trim and mean draft?
    • Answer: A (Trim 0.2 m by stern, mean 8.5 m)
    • Calculation: Trim = A − F = 0.2 m by stern; Mean draft = (F + A)/2 = 8.5 m.

  • Q62. Center of gravity above metacenter

    • Question: If center of gravity moves above metacenter, the vessel becomes:
    • Answer: B (Unstable)
    • Concept: Unsafe stability when G rises above M.

  • Q63. Righting arm increases as

    • Question: The righting arm increases as:
    • Answer: C (GM increases)
    • Note: Larger GM generally yields a larger righting arm up to limits.

  • Q64. Primary risk of free surface effect

    • Question: The primary risk of free surface effect is:
    • Answer: D (Decreased stability)

  • Q65. Ballast tank with moving water

    • Question: A ballast tank contains water free to move. What is the effect?
    • Answer: B (Reduces GM)
    • Insight: Free-surface wicked effect reduces stability.

  • Q66. Rule for proper lookout

    • Question: Which Rule requires vessels to maintain a proper lookout?
    • Answer: A (Rule 5)

  • Q67. Restricted visibility actions

    • Question: In restricted visibility, what must all vessels do?
    • Answer: C (Navigate at safe speed and sound signals)
    • Emphasis: Safe speed and appropriate sound signaling are essential.

  • Q68. Lights for power-driven vessels underway

    • Question: Power-driven vessels underway must display which lights?
    • Answer: B (Masthead, sidelights, and stern light)

  • Q69. Signal for vessel altering course to port

    • Question: What is the sound signal for a vessel altering course to port?
    • Answer: B (Two short blasts)
    • Rule reference: COLREGS signaling conventions.

  • Q70. Rule 13 applicability

    • Question: Rule 13 applies to:
    • Answer: C (Overtaking situation)
    • Context: Overtaking scenarios require the overtaken vessel to be aware and take action as necessary.

  • Q71. Not under command display

    • Question: A vessel "not under command" must display:
    • Answer: A (Two all-round red lights in a vertical line)

  • Q72. Give-way vessel action

    • Question: What is the action of the give-way vessel?
    • Answer: C (Take early and substantial action to avoid collision)

  • Q73. Rule 6 focus

    • Question: Rule 6 concerns:
    • Answer: B (Safe speed)

  • Q74. Stand-on vessel in crossing situation

    • Question: Who is the stand-on vessel in a crossing situation?
    • Answer: B (Vessel on starboard side)
    • Principle: The vessel on the starboard side has the right of way if there is a crossing.

  • Q75. Overtaking sail vs power vessel responsibility

    • Question: A sailing vessel overtaking a power-driven vessel shall:
    • Answer: A (Keep out of the way)
    • Principle: The overtaking vessel must take action to avoid the other vessel.

  • Q76. Signal for danger or doubt

    • Question: What is the signal for danger or doubt?
    • Answer: B (Five short blasts)
    • Context: Used to indicate danger or uncertainty about another vessel’s actions.

  • Q77. Fishing vessel not engaged in fishing

    • Question: A fishing vessel not engaged in fishing should be treated as:
    • Answer: A (Power-driven)

  • Q78. Two short blasts meaning

    • Question: What do two short blasts mean?
    • Answer: C (Altering to port)

  • Q79. Vessel constrained by her draft – who must keep out

    • Question: Which vessel shall keep out of the way of a vessel constrained by her draft?
    • Answer: D (All of the above)
    • Note: All vessels must take action to avoid collision with constrained-by-draft vessel.

  • Q80. Aground lights

    • Question: A vessel aground displays:
    • Answer: D (Two red lights and anchor lights)

  • Q81. IALA Region A – port mark color/top

    • Question: In IALA Region A, a port lateral mark is:
    • Answer: A (Red with can top mark)

  • Q82. Isolated danger mark color/marking

    • Question: An isolated danger mark is:
    • Answer: C (Black with one or more red bands)

  • Q83. Cardinal mark purpose

    • Question: A cardinal mark indicates:
    • Answer: C (Direction of safe water)
    • Cardinals convey which side is safe water relative to the mark (N, S, E, W).

  • Q84. Preferred channel to port mark color

    • Question: Preferred channel to port mark is:
    • Answer: A (Green with red band)

  • Q85. Safe water mark appearance

    • Question: What does a safe water mark look like?
    • Answer: C (Red and white vertical stripes)

  • Q86. Instrument showing heading

    • Question: What instrument shows the ship’s heading?
    • Answer: C (Gyrocompass)

  • Q87. Radar medium

    • Question: The radar uses:
    • Answer: C (Radio waves)

  • Q88. What does ECDIS stand for?

    • Question: What does ECDIS stand for?
    • Answer: A (Electronic Chart Display and Information System)

  • Q89. AIS information

    • Question: AIS provides information about:
    • Answer: B (Ship’s identity and position)

  • Q90. Function of a log

    • Question: What is the function of a log?
    • Answer: C (Measures ship’s speed and distance)

  • Q91. GPS purpose on ships

    • Question: What is the GPS primarily used for on ships?
    • Answer: B (Position fixing)

  • Q92. Equipment using magnetism

    • Question: Which equipment uses magnetism for direction?
    • Answer: B (Magnetic compass)

  • Q93. Echo sounder measures

    • Question: Echo sounder measures:
    • Answer: D (Depth)

  • Q94. Lateral mark color in IALA A for starboard side

    • Question: Which color is used for starboard lateral mark in IALA A?
    • Answer: B (Green)

  • Q95. Mark for new dangers

    • Question: What mark is used to indicate new dangers?
    • Answer: B (Emergency wreck marking buoy)

  • Q96. Shape of starboard lateral buoy in IALA A

    • Question: What is the shape of a starboard lateral buoy in IALA Region A?
    • Answer: B (Cone)

  • Q97. Yellow buoy with horizontal black band meaning

    • Question: A yellow buoy with a horizontal black band marks:
    • Answer: D (New danger)

  • Q98. How echo sounder works

    • Question: An echo sounder works by:
    • Answer: C (Measuring sound wave return time)
    • Principle: Time-of-flight of emitted sound waves = depth.

  • Q99. Equipment showing surrounding vessel echoes

    • Question: Which equipment shows surrounding vessel echoes?
    • Answer: C (Radar)

  • Q100. AIS update interval for fast-moving vessels

    • Question: AIS updates ship data at what interval for fast-moving vessels?
    • Answer: B (Every 3 seconds)
    • Note: AIS broadcasts are frequent for high-speed traffic to improve tracking and collision avoidance.

  • Key formulas and constants to remember

    • Nautical mile to meters: 1\ \text{NM} = 1852\ \text{m}
    • Distance per degree of latitude: 1^{\circ} \text{ latitude} = 60\ \text{NM}
    • Time = Distance / Speed; Speed = Distance / Time; Distance = Speed × Time
    • Example: Time for 100 NM at 12 kn: t = \frac{100}{12} \approx 8.33\ \text{h} = 8\text{ h }20\text{ m}
    • Example: Mean draft from FWD/AFT drafts: \text{Mean draft} = \frac{F + A}{2}; \text{Trim by stern} = A - F
    • Air draft calculation: \text{Air draft} = \text{Masthead height above keel} - \text{Draft}

  • Practical navigation implications and connections

    • Planning and lookout: Appraisal phase includes ENC coverage checks and warnings (Q29) and parallel indexing (Q27) during port arrival.
    • Stability awareness: GM, free surface effect, and squat (Q63–Q65) are critical for safe loading and maneuvering in restricted waters.
    • COLREGS and right-of-way: Understand stand-on vs give-way roles (Q74–Q75) and signaling patterns (Q69, Q70, Q76).
    • Chart and equipment literacy: Mercator projections (Q9), ENC/ECDIS (Q88), AIS (Q89), radar (Q87), gyrocompass (Q86), echo sounder (Q15, Q93).
    • Weather literacy: Barometer, cloud types, fronts, and wind scales (Q31–Q39, Q40) to anticipate conditions and plan routes.

  • Practical tips for exam success

    • Memorize key numbers and definitions (NM, 1852 m; 60 NM per degree of latitude).
    • Commit core formulae (time, distance, speed) and common navigation constants.
    • Understand relationships (variation vs deviation; true wind vs apparent wind; GM vs stability).
    • Practice converting between units (m, NM, knots, hours) and applying basic arithmetic to ETA and leg times.

  • Ethical and professional implications

    • Accurate position fixing and continuous monitoring are essential for collision avoidance and safe navigation.
    • Proper lookouts, adherence to safe speed in restricted visibility, and compliance with COLREGS demonstrate professional responsibility and safety-first judgment.

  • Quick reference cheat-sheet highlights

    • 1 NM = 1852 m; 1° latitude = 60 NM; 1° longitude varies with latitude.
    • Mercator projection is most common for navigation charts.
    • DSC, AIS, ECDIS, and radar are core modern navigation tools.
    • Basic weather awareness (barometer; cloud types; wind cues) improves voyage planning.