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SAMSA Skipper Category B (Coastal, up to 40 nm) Exam (South Africa) study materials
SAMSA Skipper Category B (Coastal, up to 40 nm) Exam (South Africa) study resources

SAMSA Skipper Category B (Coastal, up to 40 nm) Exam (South Africa) practice questions

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Question 1Navigation and Position Fixing

On a nautical chart, what does the chart datum (Chart Datum / Lowest Astronomical Tide) represent for the mariner?

  1. The reference level from which charted depths and drying heights are measured Correct answer.
  2. The level of the seabed at the deepest point of the charted area
  3. The height of the highest tide ever recorded in the area
  4. The average sea level used for all tidal predictions

Explanation

Chart datum is the low-water reference plane from which soundings (depths) and drying heights on a chart are measured. Depths shown are therefore the minimum expected, and heights above datum are drying heights. It is normally set close to Lowest Astronomical Tide so that actual depth is usually at least the charted figure.

Question 2Navigation and Position Fixing

What is the standard direction convention for expressing a course or bearing in marine navigation?

  1. Measured counter-clockwise from true north, from 000° to 360°
  2. Measured clockwise from true south, from 000° to 360°
  3. Measured clockwise from magnetic north, from 000° to 360°
  4. Measured clockwise from true north, from 000° to 360° Correct answer.

Explanation

Bearings and courses are expressed as three-figure angular measurements taken clockwise from true north (or magnetic north when stated), running from 000° up to 360°. This convention removes ambiguity of quadrant notation. Clockwise from north is the universal marine standard.

Question 3Navigation and Position Fixing

A vessel is steering a course of 090° True. What is the equivalent course in degrees Magnetic if the local variation is 12° West?

  1. 078° Magnetic
  2. 102° Magnetic Correct answer.
  3. 090° Magnetic
  4. 068° Magnetic

Explanation

The rule is: True to Magnetic, apply variation in the opposite sense to its name. With West variation, add it to the true course. So 090° True + 12° West = 102° Magnetic.

Question 4Navigation and Position Fixing

A vessel's compass shows a heading of 200° Compass. If the deviation for that heading is 4° East, what is the compass heading in degrees Magnetic?

  1. 192° Magnetic
  2. 200° Magnetic
  3. 204° Magnetic
  4. 196° Magnetic Correct answer.

Explanation

Compass to Magnetic: apply deviation in the opposite sense to its name. With East deviation, subtract it. So 200° Compass − 4° East = 196° Magnetic.

Question 5Navigation and Position Fixing

A vessel is making good a course of 045° True at 8 knots. After 3 hours, what is the approximate distance run and the position change in latitude and longitude?

  1. 24 nm; about 17 nm north and 24 nm east
  2. 24 nm; about 17 nm north and 17 nm east Correct answer.
  3. 24 nm; about 24 nm north and 0 nm east
  4. 8 nm; about 6 nm north and 6 nm east

Explanation

Distance = speed × time = 8 × 3 = 24 nm. On a 045° course the vessel travels equally north and east, so each component is 24 × cos 45° ≈ 17 nm. The position changes about 17 nm north and 17 nm east.

Question 6Navigation and Position Fixing

What is the primary purpose of a position fix in coastal navigation?

  1. To determine the vessel's fuel consumption rate
  2. To establish the vessel's actual position from observed navigational data Correct answer.
  3. To calculate the effect of tidal stream on the course
  4. To record the vessel's speed through the water

Explanation

A fix is a position determined from observed data such as bearings, ranges, or GPS, giving the vessel's actual position on the chart. It is used to confirm or correct the dead-reckoning position. Speed, tide and fuel are separate calculations.

Question 7Navigation and Position Fixing

You take a bearing on a single identifiable landmark. What does this bearing alone establish about your position?

  1. The vessel's speed over the ground
  2. The vessel's distance from the landmark
  3. A line of position along which the vessel lies Correct answer.
  4. A precise fix at a single point

Explanation

A single bearing gives one line of position (a position line) drawn from the landmark on the reciprocal bearing. The vessel lies somewhere on that line, but a second line of position is needed to obtain a fix. Distance and speed require other data.

Question 8Navigation and Position Fixing

Two position lines cross at an angle of about 30°. What is the main weakness of this fix?

  1. The fix is more accurate because the lines meet
  2. Small errors in either bearing produce a large uncertainty in the fix Correct answer.
  3. The fix cannot be plotted on a chart
  4. The fix always plots to the south of the true position

Explanation

The accuracy of a fix improves as the angle of cut approaches 90°. When lines of position cross at a small angle such as 30°, any small bearing error is magnified into a large positional error. A good fix uses lines crossing as near to right angles as practical.

Question 9Navigation and Position Fixing

What does a 'cocked hat' on a chart represent?

  1. The area of charted shallow water around a hazard
  2. The sector of a light's nominal range
  3. The area covered by the vessel's turning circle
  4. The small triangle formed when three position lines do not meet at a single point Correct answer.

Explanation

When three position lines are plotted and, due to small observational errors, they form a small triangle rather than intersecting at one point, that triangle is called a cocked hat. The vessel's position is assumed to be near its centre. It indicates the uncertainty in the fix.

Question 10Navigation and Position Fixing

On a Mercator projection chart, what does a straight line drawn between two points represent?

  1. A rhumb line of constant course Correct answer.
  2. A line of equal magnetic variation
  3. The shortest distance over the earth's surface
  4. A great circle track

Explanation

On a Mercator chart, meridians are parallel vertical lines and a straight line cuts every meridian at the same angle, so it represents a rhumb line of constant course. A great circle appears curved on a Mercator chart except along the equator or a meridian.

Question 11Navigation and Position Fixing

On a Mercator chart, how does the scale change with latitude?

  1. It changes only along the equator
  2. It remains constant across the whole chart
  3. It increases towards the poles as the latitude scale expands Correct answer.
  4. It decreases towards the poles as the latitude scale contracts

Explanation

The Mercator projection stretches the latitude scale progressively towards the poles to keep meridians parallel. Scale therefore increases with latitude, which is why distances should be measured on the latitude scale at the same latitude as the area of interest.

Question 12Navigation and Position Fixing

When measuring a distance on a nautical chart, which part of the chart should be used as the scale?

  1. The longitude scale along the top or bottom edge
  2. The latitude scale at the same latitude as the distance being measured Correct answer.
  3. The printed scale bar in the chart title only
  4. The compass rose diameter

Explanation

One minute of latitude equals one nautical mile, but on a Mercator chart the latitude scale expands towards the poles. The correct method is to measure against the latitude scale at the same latitude as the distance, so the expanded scale is accounted for. Longitude scale is not a reliable distance measure.

Question 13Navigation and Position Fixing

A nautical mile corresponds to how many minutes of latitude?

  1. One degree of latitude
  2. Ten minutes of latitude
  3. One minute of latitude Correct answer.
  4. One minute of longitude at the equator

Explanation

By definition, one nautical mile equals one minute of latitude (approximately 1 852 metres). This relationship is the basis for measuring distance on the latitude scale of a chart.

Question 14Navigation and Position Fixing

What is the difference between true bearing and relative bearing?

  1. True bearing is measured from the vessel's bow; relative bearing from north
  2. True bearing and relative bearing are always identical
  3. True bearing is measured from magnetic north; relative bearing from true north
  4. True bearing is measured from north; relative bearing from the vessel's heading Correct answer.

Explanation

A true bearing is measured clockwise from true north to the object. A relative bearing is measured clockwise from the vessel's heading (bow) to the object. To convert relative to true, add the relative bearing to the vessel's true heading.

Question 15Navigation and Position Fixing

A vessel is steering 060° True. A lighthouse bears 030° on the vessel's relative bearing scale. What is the true bearing of the lighthouse?

  1. 330° True
  2. 090° True Correct answer.
  3. 030° True
  4. 060° True

Explanation

True bearing = true heading + relative bearing. So 060° + 030° = 090° True. If the total exceeds 360°, subtract 360°.

Question 16Navigation and Position Fixing

What is meant by 'set' and 'drift' in relation to tidal stream?

  1. Set is the speed of the tidal stream; drift is its direction
  2. Set is the range of tide; drift is the time of high water
  3. Set is the rise of tide; drift is the fall of tide
  4. Set is the direction towards which the tidal stream flows; drift is its rate in knots Correct answer.

Explanation

Set is the direction in which the tidal stream is flowing (expressed as a true bearing towards which it sets). Drift is the speed or rate of the stream, usually in knots. Together they describe the tidal stream vector used in passage planning.

Question 17Navigation and Position Fixing

A vessel's speed through the water is 6 knots. A tidal stream sets the vessel at 2 knots directly on the bow. What is the approximate speed made good over the ground?

  1. 4 knots Correct answer.
  2. 8 knots
  3. 6 knots
  4. 12 knots

Explanation

When the tidal stream opposes the vessel's course directly, its effect is subtracted from the speed through the water. Speed made good = 6 − 2 = 4 knots. A stream on the bow reduces the speed over the ground.

Question 18Navigation and Position Fixing

What is the difference between a 'safe water mark' and a 'cardinal mark' in the IALA buoyage system?

  1. A safe water mark marks a wreck; a cardinal mark marks a channel entrance
  2. A safe water mark indicates navigable water all around; a cardinal mark indicates the safe side to pass a hazard by compass direction Correct answer.
  3. A safe water mark indicates a hazard; a cardinal mark indicates deep water
  4. A safe water mark is always red; a cardinal mark is always green

Explanation

A safe water mark (red and white vertical stripes, often with a red sphere topmark) shows that there is navigable water all around it, typically at a channel entrance or mid-channel. A cardinal mark indicates, by its compass direction (N, E, S or W), the side on which safe water lies relative to a hazard.

Question 19Navigation and Position Fixing

A North cardinal mark indicates that safe water lies in which direction from the mark?

  1. To the east of the mark
  2. To the north of the mark Correct answer.
  3. All around the mark
  4. To the south of the mark

Explanation

A cardinal mark is named for the direction in which safe water lies. A North cardinal mark (black over yellow, with two upward cones) indicates that the navigable water is to the north of the mark, so the vessel should pass to the north of it.

Question 20Navigation and Position Fixing

What does a charted light characteristic of 'Fl(3) R 10s' indicate?

  1. A red light visible for 10 nautical miles
  2. A fixed red light lasting 10 seconds
  3. A red light flashing once every 3 seconds
  4. A group of three red flashes followed by a period of 10 seconds Correct answer.

Explanation

Fl(3) R 10s means a flashing light in a group of three red flashes within a total period of 10 seconds. The number in brackets gives the flashes per group, the letter gives the colour, and the final number is the period in seconds.

Question 21Navigation and Position Fixing

What is the purpose of a leading line (transit) in coastal navigation?

  1. To mark the boundary of a prohibited area
  2. To show the direction of the prevailing wind
  3. To indicate the depth of water in a channel
  4. To keep the vessel on a safe track by aligning two charted marks Correct answer.

Explanation

A leading line is formed by two marks, such as beacons or structures, that appear in line when the vessel is on the correct track. Keeping them aligned keeps the vessel on a safe course through a channel or clear of a hazard.

Question 22Navigation and Position Fixing

A vessel at anchor is swinging. Which method best checks that the anchor is not dragging?

  1. Measuring the depth of water under the keel once
  2. Checking the colour of the anchor buoy
  3. Taking a series of bearings and ranges to fixed charted objects over time Correct answer.
  4. Reading the vessel's speed through the water on the log

Explanation

Regular bearings and ranges to fixed objects, plotted over time, reveal whether the vessel's position is changing relative to the seabed. If the plotted positions move outside the swinging circle, the anchor may be dragging. A single depth reading or the log does not reliably show dragging.

Question 23Navigation and Position Fixing

In South African coastal waters, what is the practical significance of the 'distance offshore' limitation (up to 40 nm) for a Category B skipper?

  1. The vessel may operate up to 40 nautical miles from the coastline, requiring adequate position-fixing and navigation equipment Correct answer.
  2. The vessel may operate only within 40 metres of the shore
  3. The vessel may operate only in daylight hours
  4. The vessel may operate only within sight of the launch site

Explanation

The Category B coastal limitation permits operation up to 40 nautical miles offshore. Because the vessel may be out of sight of land, reliable position fixing (such as GPS with chart backup) and sound coastal navigation are essential.

Question 24Navigation and Position Fixing

A vessel steams 000° True for 12 nm, then 090° True for 16 nm. What is the approximate distance and bearing of the final position from the start?

  1. 28 nm on 045°
  2. 16 nm on 090°
  3. 20 nm on approximately 037°
  4. 20 nm on approximately 053° Correct answer.

Explanation

The legs form a right triangle with sides 12 nm north and 16 nm east. Distance = √(12² + 16²) = √400 = 20 nm. The bearing from start = arctan(16/12) ≈ 53°, measured from north towards east, so about 053° True.

Question 25Navigation and Position Fixing

You plot a fix and find it lies 2 nm to the north-east of your dead-reckoning position after 4 hours. What is the most likely explanation?

  1. The compass has no deviation
  2. The chart datum is incorrect
  3. The log is reading too high
  4. An unaccounted tidal stream or current has been setting the vessel to the north-east Correct answer.

Explanation

A consistent offset of the fix from the DR position in one direction usually indicates an external force, such as a tidal stream or current, that was not included in the DR calculation. The fix reveals the actual track, and the difference gives an indication of set and drift.

Question 26Navigation and Position Fixing

When plotting a position using a magnetic compass bearing to a landmark, what must be applied before drawing the position line on a chart?

  1. Neither, compass bearings are true
  2. Variation only
  3. Both deviation and variation Correct answer.
  4. Deviation only

Explanation

A compass bearing is affected by both deviation (on the vessel) and variation (at the location). To convert a compass bearing to a true bearing for plotting, you must apply both corrections, typically in the order: compass to magnetic (apply deviation), then magnetic to true (apply variation).

Question 27Navigation and Position Fixing

What is the primary advantage of taking a fix using three position lines from widely separated landmarks?

  1. It provides a check on the accuracy of the position lines Correct answer.
  2. It allows the vessel to be located without a chart
  3. It automatically corrects for tidal stream
  4. It eliminates the need for a compass

Explanation

Three position lines will, in theory, intersect at a single point if all are accurate. Any small triangle (cocked hat) indicates errors in the observations or plotting, providing a check on accuracy. Two lines give a fix but no internal check.

Question 28Navigation and Position Fixing

On a nautical chart, what does a position line represent?

  1. The vessel's track over the ground
  2. The exact position of the vessel
  3. The boundary of a restricted area
  4. A line along which the vessel must be located Correct answer.

Explanation

A position line is a line on the chart along which the vessel's position is known to lie, derived from a bearing, range, or other observation. A single position line does not give a fix; at least two are needed to determine a position.

Question 29Navigation and Position Fixing

What is the purpose of a dead reckoning (DR) plot?

  1. To calculate the effect of wind on the vessel's heading
  2. To estimate the vessel's position from course, speed, and time Correct answer.
  3. To determine the vessel's position by visual bearings
  4. To measure the depth of water beneath the vessel

Explanation

Dead reckoning (DR) is the process of estimating position by advancing a known position using the vessel's course, speed, and elapsed time, without reference to external landmarks. It provides an approximate position between fixes.

Question 30Navigation and Position Fixing

With no leeway, a vessel moves through the water on heading 045° True at 8 knots. The current sets toward 090° True at 3 knots. What is approximate speed over the ground?

  1. 10.3 knots Correct answer.
  2. 11 knots
  3. 8.5 knots
  4. 5 knots

Explanation

The through-water and current velocity vectors differ by 45°. Speed over ground is √(8² + 3² + 2 × 8 × 3 × cos 45°) ≈ 10.34 knots, or 10.3 knots to one decimal place.

Question 31Navigation and Position Fixing

When using a hand-bearing compass, what is the recommended practice to reduce bearing errors?

  1. Take several bearings and average them Correct answer.
  2. Use the compass without checking for deviation
  3. Always take bearings from the same side of the vessel
  4. Take the bearing quickly while the vessel is rolling

Explanation

Taking multiple bearings and averaging them reduces random errors from vessel motion and observation. It is also good practice to take bearings when the vessel is steady and to check the compass for deviation.

Question 32Navigation and Position Fixing

You observe a lighthouse bearing 090° True and, at the same time, measure its range as 5 nautical miles using radar. How would you plot this fix on the chart?

  1. Draw a line at 090° from the vessel's DR position and mark 5 nm along it
  2. Draw a circle of radius 5 nm around the lighthouse and a line at 090°; the intersection is the fix Correct answer.
  3. Plot a single point at the lighthouse and offset by 5 nm in the direction of 090°
  4. Draw a line from the lighthouse at 090° and mark the position at 5 nm along that line

Explanation

A bearing and a range from the same object give two position lines: a line of bearing and a circle of equal range. Their intersection is the fix. This is a common and reliable method when using radar.

Question 33Navigation and Position Fixing

What does a charted light characteristic of 'Oc(2) G 8s' indicate?

  1. A green light occulting twice in a period of 8 seconds Correct answer.
  2. A group of two green flashes every 8 seconds
  3. A green light showing two long flashes every 8 seconds
  4. A fixed green light with two occultations per minute

Explanation

The abbreviation 'Oc' stands for occulting, meaning the light is on for longer than it is off, with darkness periods. 'Oc(2) G 8s' means two occultations (dark periods) in a group, green in color, with a total period of 8 seconds.

Question 34Navigation and Position Fixing

In the IALA Region A buoyage system, what is the significance of the direction of buoyage?

  1. It defines the order of lateral marks when entering a harbour Correct answer.
  2. It indicates the direction of the prevailing current
  3. It marks the boundary between safe and unsafe water
  4. It shows the direction of the magnetic north

Explanation

In IALA Region A, the direction of buoyage is the direction taken by a vessel entering a harbour from seaward, or the general direction of the main channel. Lateral marks are coloured red (port) and green (starboard) according to this direction.

Question 35Navigation and Position Fixing

When plotting a fix using two position lines that intersect at a very small angle, what is the main problem?

  1. The fix requires a third position line to be valid
  2. The fix cannot be plotted on a Mercator chart
  3. The fix is more accurate because the lines are nearly parallel
  4. The fix is unreliable because a small error in either bearing causes a large position error Correct answer.

Explanation

When position lines intersect at a small angle (less than about 30°), the intersection point is poorly defined; a small error in either bearing results in a large displacement of the fix. Ideally, position lines should cross at angles close to 90°.

Question 36Navigation and Position Fixing

What is the effect of leeway on a vessel's course over the ground?

  1. It causes the magnetic compass to deviate
  2. It has no effect on the vessel's track
  3. It increases the vessel's speed through the water
  4. It pushes the vessel sideways, so the course steered must be adjusted to maintain the desired track Correct answer.

Explanation

Leeway is the sideways drift of a vessel caused by wind. To maintain a desired track over the ground, the vessel must steer a course angled into the wind to compensate for leeway.

Question 37Navigation and Position Fixing

You are navigating in fog and hear a fog signal from a lighthouse. What does a fog signal of one long blast every 30 seconds indicate?

  1. A vessel underway, making way
  2. A vessel not under command
  3. A vessel at anchor
  4. A lighthouse with a foghorn that sounds once every 30 seconds Correct answer.

Explanation

Fog signals from lighthouses are described in sailing directions and on charts. A single long blast every 30 seconds is a typical characteristic for a lighthouse fog signal. Vessels have different signals: a power-driven vessel making way sounds one prolonged blast at intervals of not more than 2 minutes.

Question 38Navigation and Position Fixing

A vessel is on a course of 000° True at 10 knots. After 2 hours, a fix shows the vessel is actually 4 nautical miles east of the DR position. What was the average set and drift of the current?

  1. Set 090° True, drift 4 knots
  2. Set 090° True, drift 2 knots Correct answer.
  3. Set 180° True, drift 2 knots
  4. Set 270° True, drift 2 knots

Explanation

The DR position after 2 hours would be 20 nm north of the start. The actual position is 4 nm east of that, so the current has set the vessel 4 nm east over 2 hours. Therefore, the set is 090° True and the drift is 4 nm / 2 h = 2 knots.

Question 39Navigation and Position Fixing

When using a GPS receiver for position fixing, what is the primary source of the position information?

  1. Radar echoes from land features
  2. Inertial navigation sensors
  3. Signals from shore-based radio beacons
  4. Signals from a network of satellites Correct answer.

Explanation

GPS (Global Positioning System) uses signals from a constellation of satellites to determine position by trilateration. It does not rely on shore-based beacons or radar.

Question 40Navigation and Position Fixing

What is the significance of a 'leading line' (transit) when navigating a channel?

  1. It marks the boundary of a prohibited area
  2. It indicates the direction of the tidal stream
  3. It shows the location of a submerged wreck
  4. It provides a visual line to keep the vessel on the correct course through a channel Correct answer.

Explanation

A leading line is formed by two charted objects aligned so that, when kept in line, the vessel follows a safe course through a channel. It is a simple and effective method of position monitoring.

Question 41Charts, Publications and Passage Planning

On a South African nautical chart, what does the abbreviation 'Lt Ho' indicate?

  1. A light vessel
  2. A lighthouse Correct answer.
  3. A light shown from a harbour wall
  4. A light buoy

Explanation

Chart abbreviations are standardised; 'Lt Ho' denotes a lighthouse, a fixed structure carrying a major light. Lightships and buoys use different abbreviations, so the structure type is the distinguishing factor.

Question 42Charts, Publications and Passage Planning

A chart is printed with the note 'Depths in metres'. A sounding shown as '12' with no subscript means what depth?

  1. 12 metres Correct answer.
  2. 120 metres
  3. 12 fathoms
  4. 1.2 metres

Explanation

The chart's stated units apply directly to the printed figures. When depths are given in metres, a whole number with no subscript is that many metres, and any decimal part is shown as a subscript.

Question 43Charts, Publications and Passage Planning

What is the primary purpose of a Notice to Mariners?

  1. To announce harbour tariffs and berthing fees
  2. To record the vessel's daily position for the log
  3. To update charts and publications with changes affecting navigation Correct answer.
  4. To list the qualifications required for crew

Explanation

Notices to Mariners are the official channel for promulgating changes to charts, sailing directions and lists of lights. Mariners apply them so that paper and electronic charts reflect current conditions.

Question 44Charts, Publications and Passage Planning

On a Mercator chart, which quantity remains constant so that a straight line represents a constant compass bearing?

  1. The height of the printed chart border
  2. The angular relationship between meridians and parallels Correct answer.
  3. The scale measured in nautical miles per inch
  4. The spacing between successive parallels of latitude

Explanation

Mercator projection preserves angles, so meridians and parallels cross at right angles and a rhumb line plots as a straight line. This is why the projection is used for marine navigation charts.

Question 45Charts, Publications and Passage Planning

In the South African system, what do the IALA Region A lateral buoy colours indicate when entering a harbour?

  1. White to starboard and blue to port
  2. Red to starboard and green to port
  3. Green to starboard and red to port Correct answer.
  4. Yellow to starboard and black to port

Explanation

South Africa uses IALA Region A, where green marks the port side and red the starboard side of the channel when proceeding in the direction of the buoyage. This is the reverse of Region B practice.

Question 46Charts, Publications and Passage Planning

What is the main purpose of a passage plan?

  1. To satisfy the harbour master's paperwork requirements
  2. To provide a documented, safe route from berth to berth Correct answer.
  3. To record the names of all crew on board
  4. To calculate the vessel's fuel consumption only

Explanation

A passage plan sets out the intended route, hazards, waypoints, contingency anchorages and safety margins from berth to berth. It is a working navigational document, not merely an administrative form.

Question 47Charts, Publications and Passage Planning

A chart shows a magenta line with a small magenta arrow and the letters 'Fl R 4s' alongside. What information does this convey?

  1. A recommended route marked by a flashing red light every four seconds Correct answer.
  2. A traffic separation scheme boundary
  3. A prohibited anchoring area
  4. A submarine cable with a four-second warning

Explanation

Magenta is used on charts for overprinted navigational information such as recommended tracks and light characteristics. 'Fl R 4s' describes a light flashing red once every four seconds.

Question 48Charts, Publications and Passage Planning

Your vessel is making 6 knots and the planned leg is 21 nautical miles long. What is the estimated passage time for the leg?

  1. 4 hours 00 minutes
  2. 3 hours 30 minutes Correct answer.
  3. 3 hours 00 minutes
  4. 2 hours 30 minutes

Explanation

Time equals distance divided by speed. Twenty-one nautical miles at six knots gives 3.5 hours, which is 3 hours 30 minutes.

Question 49Charts, Publications and Passage Planning

A chart extract states 'Heights in metres above MHWS'. A lighthouse is marked 'Lt Ho 28'. What does the 28 represent?

  1. The height of the light above mean high water springs Correct answer.
  2. The height of the tower above the shoreline
  3. The height of the lamp above the chart datum
  4. The distance in nautical miles the light is visible

Explanation

Light heights on charts are given above a stated datum, commonly mean high water springs in South African waters. The stated datum must be read with the figure.

Question 50Charts, Publications and Passage Planning

Which publication would you consult to find the tidal stream rates and times for a South African port?

  1. The tide tables and tidal stream atlas for the region Correct answer.
  2. The list of lights and fog signals
  3. The annual Notice to Mariners summary
  4. The sailing directions for the area

Explanation

Tide tables give predicted heights and times, while tidal stream atlases give the rate and direction of the current. Together they are the correct source for tidal stream information.