100+ Free SAMSA Certificate of Competency (CoC) Deck Officer in Charge of a Navigational Watch (OICNW) Exam (South Africa) Practice Questions

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Key Facts: SAMSA Certificate of Competency (CoC) Deck Officer in Charge of a Navigational Watch (OICNW) Exam (South Africa) Exam

70%

Passing Score

SAMSA / STCW

3 hours

Exam Time

SAMSA Standard

R 2,500

Exam Fee

SAMSA Schedule

Prepare for the SAMSA Deck OICNW (STCW Section A-II/1) Certificate of Competency examination with our 100-question practice test bank. Please note: Our 100 MCQs are an English-language MCQ study adaptation for SAMSA examinations.

Sample SAMSA Certificate of Competency (CoC) Deck Officer in Charge of a Navigational Watch (OICNW) Exam (South Africa) Practice Questions

Try these sample questions to test your SAMSA Certificate of Competency (CoC) Deck Officer in Charge of a Navigational Watch (OICNW) Exam (South Africa) exam readiness. Each question includes a detailed explanation. Start the interactive quiz above for the full 100+ question experience with AI tutoring.

1What is the true azimuth of a celestial body defined as?

A.The arc of the horizon between the north direction and the vertical circle passing through the body

B.The angle measured at the zenith between the observer's magnetic meridian and the body

C.The angle between the prime vertical and the celestial equator

D.The vertical angle measured from the observer's horizon up to the body

Explanation: True azimuth is defined as the arc of the horizon measured clockwise from true north (000° to 360°) to the vertical circle passing through the celestial body. It provides the true bearing of the celestial body relative to true north. Understanding true azimuth is fundamental for compass error determination.

2On a standard Mercator nautical chart, how is distance measured correctly?

A.Using the longitude scale at the top or bottom of the chart

B.Using the latitude scale at the same latitude as the distance being measured

C.Using a fixed scale factor of 1 millimeter equals 1 nautical mile anywhere on the chart

D.Using the distance key provided in the title block of the chart

Explanation: On a Mercator projection, latitude lines expand progressively away from the equator. Therefore, 1 minute of latitude equals 1 nautical mile only at that specific latitude, requiring distance to be measured on the latitude scale alongside the area being measured.

3What causes magnetic compass variation?

A.Ferrous metal and electrical circuits within the vessel

B.Frictional resistance in the compass card pivot assembly

C.Angular difference between geographic true north and magnetic north at a specific location

D.Rolling and pitching motions of the ship in heavy seas

Explanation: Variation is caused by the earth's magnetic poles not aligning with geographic true poles. It varies geographically and changes over time, as indicated on the chart compass rose.

4What is the primary characteristic of a rhumb line on a nautical chart?

A.It represents the shortest distance between two points on the Earth's surface

B.It constantly updates the vessel's true heading automatically

C.It appears as a curved line on a Mercator chart

D.It cuts all meridians at the same angle

Explanation: A rhumb line (loxodromic curve) crosses all geographic meridians at a constant angle. On a Mercator chart, rhumb lines appear as straight lines, making course plotting straightforward.

5What coordinates define the Geographical Position (GP) of a celestial body on Earth?

A.Greenwich Hour Angle (GHA) and Declination (Dec)

B.Local Hour Angle (LHA) and Altitude (Alt)

C.Right Ascension (RA) and Sidereal Hour Angle (SHA)

D.Zenith Distance (ZD) and True Azimuth (Zn)

Explanation: The Geographical Position (GP) is the point on Earth's surface directly beneath a celestial body. Its latitude corresponds to the body's Declination (Dec) and its longitude corresponds to the body's Greenwich Hour Angle (GHA).

6When do Spring Tides occur during the lunar month?

A.When the Sun and Moon are at right angles to each other (First and Third Quarters)

B.When the Sun, Earth, and Moon are aligned (New Moon and Full Moon)

C.When the Moon is at apogee (furthest from Earth)

D.When the Earth is at perihelion (closest to the Sun)

Explanation: Spring tides occur during New Moon and Full Moon when the gravitational forces of the Sun and Moon reinforce each other (syzygy), resulting in the highest high tides and lowest low tides.

7What reference datum is standard for soundings on modern South African nautical charts?

A.Mean Sea Level (MSL)

B.Highest Astronomical Tide (HAT)

C.Lowest Astronomical Tide (LAT)

D.Mean High Water Springs (MHWS)

Explanation: Modern nautical charts published by the South African Navy Hydrographic Office use Lowest Astronomical Tide (LAT) as Chart Datum. Soundings shown on charts represent water depth below LAT.

8If magnetic variation is 18° West and compass deviation is 3° East, what is the total compass error?

A.21° West

B.15° East

C.21° East

D.15° West

Explanation: Total Compass Error = Variation + Deviation. Combining 18° West and 3° East yields 15° West (since West is negative and East is positive: -18° + 3° = -15° or 15° West).

9What information is used exclusively to plot a Dead Reckoning (DR) position?

A.Last known fix, ordered course, and log speed through water without allowing for wind or current

B.Visual bearings, radar ranges, and satellite coordinates

C.Soundings, tidal stream set/drift, and leeway angle

D.Estimated current velocity and observed wind leeway

Explanation: A Dead Reckoning (DR) position is calculated using only the vessel's previous known position, true course steered, and speed through the water over elapsed time, intentionally excluding external factors like set, drift, and leeway.

10At local apparent noon (meridian passage), what is the Local Hour Angle (LHA) of the Sun?

A.090°

B.000° (or 360°)

C.180°

D.270°

Explanation: Local apparent noon occurs when the Sun crosses the observer's meridian. At this instant, the celestial body lies directly on the observer's celestial meridian, so its Local Hour Angle (LHA) is 000° (or 360°).

About the SAMSA Certificate of Competency (CoC) Deck Officer in Charge of a Navigational Watch (OICNW) Exam (South Africa) Exam

Comprehensive practice question bank for the SAMSA Certificate of Competency (CoC) Deck Officer in Charge of a Navigational Watch (OICNW) examination. Note: Our 100 MCQs are an English-language MCQ study adaptation for SAMSA examinations.

Assessment

Question count not published by the exam provider

Time Limit

3 hours

Passing Score

70%

Exam Fee

R 2,500 (South African Maritime Safety Authority (SAMSA) / STCW Section A-II/1)

SAMSA Certificate of Competency (CoC) Deck Officer in Charge of a Navigational Watch (OICNW) Exam (South Africa) Exam Content Outline

30%

Celestial & Terrestrial Navigation & Chartwork

Celestial line of position, terrestrial position fixing, sailings, tides, and navigational publications.

30%

COLREGs 1972 & Watchkeeping Procedures

International Regulations for Preventing Collisions at Sea 1972 and STCW Code watchkeeping principles.

20%

Radar/ARPA, ECDIS & Bridge Electronics

Radar interpretation, ARPA vector analysis, ECDIS safety settings, GNSS, and gyro/magnetic compasses.

20%

Cargo Operation & Basic Vessel Stability

Cargo stowage, securing, dangerous goods handling, hydrostatic tables, transverse stability, and trim.

How to Pass the SAMSA Certificate of Competency (CoC) Deck Officer in Charge of a Navigational Watch (OICNW) Exam (South Africa) Exam

What You Need to Know

Passing score: 70%
Assessment: Question count not published by the exam provider
Time limit: 3 hours
Exam fee: R 2,500

Keys to Passing

Work through all 100 available questions
Review every answer and explanation
Track weak areas and revisit them
Use our AI tutor for tough concepts

SAMSA Certificate of Competency (CoC) Deck Officer in Charge of a Navigational Watch (OICNW) Exam (South Africa) Study Tips from Top Performers

1Memorize COLREGs Rules 1 to 19 verbatim along with risk of collision evaluation steps.

2Practice manual radar plotting techniques (OAW triangles) and ARPA vector interpretations.

3Review celestial navigation formulas including altitude corrections, azimuth calculations, and meridian passage.

4Master vessel stability concepts such as GM, GZ, KB, KM, list vs heel, and free surface effect calculations.

Frequently Asked Questions

What authority governs the SAMSA Deck OICNW Certificate of Competency in South Africa?

The South African Maritime Safety Authority (SAMSA) administers the CoC examination in compliance with the International Maritime Organization (IMO) STCW Convention Section A-II/1 standards.

What topics are covered in the SAMSA Deck OICNW examination?

The exam covers Celestial & Terrestrial Navigation & Chartwork (30%), COLREGs 1972 & Watchkeeping Procedures (30%), Radar/ARPA, ECDIS & Bridge Electronics (20%), and Cargo Operations & Basic Vessel Stability (20%).

How are these practice questions structured?

Our 100 MCQs are an English-language MCQ study adaptation for SAMSA examinations, designed to help candidates prepare for oral and written assessments across all key STCW A-II/1 competencies.