SBF Coastal navigation task –
step by step

What the navigation task is in the exam

The theory exam for the SBF Coastal consists of a question paper with 30 questions (7 basic, 23 specific coastal questions) and a navigation task with 9 sub-questions. You answer the sub-questions in writing and plot courses and positions on the chart excerpt that belongs to your paper. That is why this part is also called the chart task.

Good to know: follow-on errors are not penalised twice. If an answer is wrong only because you correctly carried forward a wrong value from an earlier sub-question, it still earns its point. So write your working down briefly, so the examiner can follow it. You may not lose more than two points.

All tasks are based on training chart D49, covering the estuaries of the Jade, Weser and Elbe. The boat’s deviation is given as a number in the task text; you take the variation from the chart.

The task types step by step

The 15 question types fall into six groups. For each one, here is the solution in a few steps. The numbers in the examples are made up and do not come from an official task.

1. Reading and plotting a course

Sub-questions “true course” (rwK) and “plot the course”

The true course (rwK) is the angle between geographic north and your course line. You read it off the chart with the navigation triangle, or you plot a given course.

1. Join the start and destination cleanly with the ruler and extend the line a little beyond both points.
2. Place the edge of the navigation triangle on the course line and slide it until the centre of the degree scale sits on a meridian (line of longitude).
3. Read the course where the meridian crosses the scale. Of the two values, use the one pointing in your direction of travel.
4. Sanity check: if you are heading roughly south-east, the course must lie between 90° and 180°.

Further reading: How to read a nautical chart

2. Course conversion: from true to compass course

Sub-question “compass course” (MgK)

The compass on board does not point to geographic north. Variation (Mw) depends on the location and the year and is shown on the chart; deviation (Abl) depends on the boat and is given in the task text. Easterly values are positive, westerly negative.

1. Read the true course from the chart (see above).
2. Bring the variation up to the year of the task: the chart gives it for a reference year with an annual change. Add the change for every year, with its sign, and round to whole degrees (under 30' down, from 30' up). In the official tasks this gives 0° or +1°.
3. Subtract the variation: true − variation = magnetic course (rwK − Mw = mwK).
4. Subtract the deviation from the task text: magnetic − deviation = compass course (mwK − Abl = MgK).
5. Check in reverse: compass + deviation + variation = true course (MgK + Abl + Mw = rwK).

Further reading: Course conversion for the SBF Coastal · Compass, variation and deviation

3. Converting and plotting bearings

Sub-questions “bearings” and “plot the bearings”

Directions to lights or buoys taken with the compass are compass bearings (MgP). For the chart you need the true bearing (rwP). The sum is the same as for the course, just in the other direction.

1. Add deviation and variation: compass bearing + deviation + variation = true bearing (MgP + Abl + Mw = rwP). Which deviation applies depends on the compass: with a bearing attachment on the steering compass, its deviation for the current heading applies, not the one for the direction of the bearing. With a hand bearing compass, the deviation is given in the task, usually 0°.
2. Place the navigation triangle so that its edge runs through the object you took the bearing on and shows the true bearing at the meridian.
3. Draw the line from the object back towards you. This position line holds every point from which the object lies in that direction.
4. Plot a second bearing on another object the same way. Where the two lines cross is your observed position.

Further reading: Bearing and collision course

4. Position, dead reckoning and dead-reckoning error

Sub-questions “geographical position”, “plot the position”, “position by dead reckoning”, “dead-reckoning error” (Besteckversetzung)

Fixing your position means reading a position off the chart, plotting a given position, or working it out in advance from course, speed and time (dead reckoning). The difference between the dead-reckoning position and the observed position is the dead-reckoning error.

1. Reading: take the latitude from the side edge of the chart and the longitude from the top or bottom edge, for example with dividers or a triangle moved parallel. Give latitude with N, longitude with E.
2. Plotting: mark latitude and longitude on the edges, carry both lines into the chart and set the position where they cross.
3. Dead reckoning: work out distance = speed × time, take that distance off the latitude scale with the dividers and mark it along the course line from the starting point. The result is the dead-reckoning position.
4. Dead-reckoning error: draw a line from the dead-reckoning position to the observed position and give its direction (true) and length in nautical miles.

Further reading: Structure of the navigation task

5. Distance, time and speed

Sub-questions “distance”, “time”, “speed”

Distances are measured in nautical miles (nm), speeds in knots (kn, nautical miles per hour). One minute of arc on the latitude scale equals one nautical mile.

1. Set the dividers on the two points and read the opening on the latitude scale (side edge), ideally at the same height as the distance. Never measure on the longitude scale at the top or bottom.
2. Time: t = d ÷ v. The result is in hours; multiply by 60 for minutes.
3. Speed: v = d ÷ t, converting the time to hours first.
4. Mental shortcut without a calculator: one nautical mile takes 60 ÷ speed minutes. At 6 kn that is 10 minutes per nautical mile.
5. If a clock time is asked for, add the passage time to the departure time.

Further reading: Nautical mile and latitude scale

6. Navigation marks and chart entries

Sub-questions “meaning” and “description of a navigation mark”, “chart entry”

These sub-questions test pure chart knowledge. You name a mark, describe a light or explain an entry. The abbreviations are listed in the chart symbol key (Chart 1 / INT 1).

1. Find the mark on the chart and read the label next to it in full.
2. For buoys, name the type (for example starboard-hand or cardinal buoy) and give colour and shape. Only mention a topmark if it is drawn on the symbol.
3. For lights, break down the characteristic: type (flashing, occulting, isophase), group, colour, period in seconds, plus elevation and range if given. If there is no colour letter, the light is white.
4. Write down everything shown on the symbol, but do not add anything. Anything missing counts as incomplete; anything guessed counts as wrong.

Further reading: Reading chart symbols

And the tides?

Tides are part of the SBF Coastal syllabus, but not part of the navigation task. None of the 15 sub-questions asks you to calculate a water level, current set or a correction for wind and current. In the question paper, tides appear as knowledge questions:

1. Terms: ebb, flood, tide, high water, low water and tidal range (the difference between high and low water heights).
2. Sources: where to find high and low water times, namely in the tide tables or tide calendar of the BSH (German Federal Maritime and Hydrographic Agency).
3. Set: what current set and leeway mean, i.e. how far and in which direction the boat is carried over ground.

For passage planning in the Wadden Sea that is not enough. How to estimate the water level between high and low water is shown in the article Calculating tides with the rule of twelfths. You do not need the calculation for the exam.

Common mistakes and how to avoid them

What equipment you need

Under the German Recreational Boat Licence Regulation, exactly these aids are allowed: navigation triangle, set square, parallel ruler, Portland plotter and dividers. Other aids, including electronic ones, are excluded. So you work without a calculator.

How to prepare

1. Learn the tools: practise reading a course, plotting a course and measuring distance until the movements are second nature.
2. Automate the sums: work through course and bearing conversions with changing signs, always with a check.
3. Solve all 15 tasks: work through every official task once in full on the paper chart and compare it with the model solution.
4. Under exam conditions: question paper and navigation task together in 60 minutes. In the Boatpass app you practise the full ELWIS catalog and every navigation task in its nine sub-questions.

How the whole exam works, from registration to the practical test, is explained on the page SBF exam: how it works.

Frequently asked questions about the navigation task

Sources (in German): ELWIS – navigation tasks, ELWIS – marking scheme, ELWIS – specific coastal questions (tides: questions 249 to 255), SpFV, Annex 3 (marking and aids). As of October 2026.