FlightDesk Aero / Question bank / PPL · Navigation
PPL(A) · EASA 061
Navigation
Answer each question, then read why: the explanation, the formula, a diagram and the solution step by step.
Chapters
- 061-01 Basics of navigation · 2
- 061-02 Magnetism and compasses · 1
- 061-03 Charts · 1
- 061-04 Dead reckoning navigation · 2
- 061-05 In-flight navigation · 2
- 062-01 Radio propagation · 0
- 062-02 Radio aids · 0
- 062-03 Radar · 0
- 062-04 GNSS · 0
Question 1 of 8
Distance along a meridian
Two airfields lie on the same meridian, at 47°25'N and 48°55'N. What is the distance between them?
Explanation
Along a meridian, one minute of latitude is one nautical mile. That is how the nautical mile was defined, which makes north–south distances the easiest sum in navigation: count the minutes of latitude and you have the miles. In the formula, d is the distance and Δφ the change of latitude.
Step by step
- Count up from A to the next whole degree: 47°25' → 48°00' = 35'.
- Then on to B: 48°00' → 48°55' = 0°55' = 55'.
- Total: 35' + 55' = 90'. One minute of latitude is one nautical mile: 90 NM.
Why not the other answers
- 150 NM treats a degree as if it had 100 minutes: 1°30' becomes 1.5 × 100. A degree has 60 minutes, so 1°30' is 90'.
- 60 NM counts only the whole degree and forgets the extra 30 minutes.
- 167 is the distance in kilometres (90 × 1.852 ≈ 167 km), not in nautical miles.
Tip. Only latitude works this way. A minute of longitude shrinks towards the poles, so east–west distances need the cosine of the latitude.
Question 2 of 8
True to magnetic: applying variation
You measure a true track of 095° on the chart. The local magnetic variation is 4°E. What is the magnetic track?
Explanation
Variation is the angle between true north and magnetic north. With an easterly variation, magnetic north lies east of true north, so every direction measured from it comes out smaller. The memory aid is: variation east, magnetic least; variation west, magnetic best. In the formula, T stands for true, M for magnetic and Var for the variation, east (E) or west (W).
Step by step
- Start from the true track: 095°T.
- Variation is east, so magnetic is least: subtract it.
- 095° − 4° = 091°M.
Why not the other answers
- 099° adds an easterly variation. That is the rule for westerly variation.
- 095° is still the true track: variation has not been applied.
- 087° subtracts the variation twice (095 − 8).
Tip. Variation comes from the isogonals printed on your chart. It changes slowly over the years, so use a recent chart.
Question 3 of 8
From true heading to compass heading
True heading 250°, variation 3°W, compass deviation 2°E on this heading. Which heading do you fly on the compass?
Optional: check your working step by step.
Explanation
Going from true to compass you apply two corrections in a fixed order: variation (the Earth's magnetic field) gives magnetic, then deviation (the aircraft's own magnetism, read from the compass deviation card) gives compass. Both follow the same sign rule: east is subtracted, west is added. In the formula, C stands for compass, T for true, Var for variation and Dev for deviation.
Step by step
- True heading: 250°T.
- Variation 3°W, west is best: 250° + 3° = 253°M.
- Deviation 2°E, east is least: 253° − 2° = 251°C.
Why not the other answers
- 255° adds the easterly deviation instead of subtracting it.
- 249° subtracts the westerly variation (247°M) and then adds the deviation: both signs are reversed.
- 245° subtracts the westerly variation and then subtracts the deviation as well.
Tip. Write the chain T → V → M → D → C at the top of your log. Going from compass back to true, every sign flips.
Question 4 of 8
Measuring distance with the chart scale
On a 1:500 000 chart you measure 18.52 cm between two turning points. What is the distance in nautical miles?
Explanation
A scale of 1:500 000 means one unit on the chart is 500 000 of the same units on the ground. Work in one unit all the way, then convert to nautical miles at the end: one nautical mile is exactly 1 852 m.
Step by step
- Chart distance times the scale denominator: 18.52 cm × 500 000 = 9 260 000 cm.
- In metres: 9 260 000 cm ÷ 100 = 92 600 m (92.6 km).
- In nautical miles: 92 600 m ÷ 1 852 m = 50 NM.
Why not the other answers
- 93 is the distance in kilometres (92.6 km). The conversion to nautical miles is missing.
- 5 NM reads 9 260 000 as millimetres instead of centimetres, so the result is ten times too small.
- 172 NM multiplies the kilometres by 1.852 instead of dividing: that turns nautical miles into kilometres, the other way round.
Tip. On a 1:500 000 chart, 1 cm is 5 km, so 10 NM is about 3.7 cm. In the cockpit the scale line on the chart edge or a navigation ruler is quicker than any arithmetic.
Question 5 of 8
Leg time from ground speed
Your TAS is 120 kt and the wind gives you a ground speed of 105 kt. How long does a 42 NM leg take?
Optional: check your working step by step.
Explanation
Time over the ground depends on ground speed, not on airspeed: the wind is carrying the whole air mass, and you with it. Divide the distance (d) by the ground speed (GS) and turn the time (t) from hours into minutes.
Step by step
- Use ground speed: 105 kt.
- Time in hours: 42 NM ÷ 105 kt = 0.4 h.
- In minutes: 0.4 × 60 = 24 min.
Why not the other answers
- 21 min uses the true airspeed, TAS (42 ÷ 120 = 0.35 h). The aircraft moves 120 kt through the air, but only 105 kt over the ground.
- 40 min reads 0.4 h as 40 minutes. An hour has 60 minutes, so 0.4 h is 24 minutes.
- 150 min turns the division upside down: 105 ÷ 42 = 2.5 h, that is 150 min.
Tip. Quick check: at 105 kt you cover 1.75 NM per minute, so 42 NM takes 24 minutes. On the navigation computer, set the ground speed against the 60 index and read the time under the distance.
Question 6 of 8
Maximum drift with the 1 in 60 rule
TAS 100 kt. The wind blows at 20 kt exactly at right angles to your track. Using the 1 in 60 rule, roughly how much drift should you expect?
Optional: check your working step by step.
Explanation
A wind at right angles to the track gives the largest drift you can get from it, the maximum drift (MD). TAS is the true airspeed and WS the wind speed. The 1 in 60 rule turns it into one line of mental arithmetic: in one hour you fly 100 NM through the air and the wind pushes you 20 NM sideways, and 1 NM off after 60 NM is 1°.
Step by step
- 60 ÷ TAS: 60 ÷ 100 = 0.6.
- Times the wind speed: 0.6 × 20 = 12°.
- Check with trigonometry: arcsin(20 ÷ 100) ≈ 11.5°, so the rule is close enough for the cockpit.
Why not the other answers
- 20° takes the wind speed in knots as degrees of drift. That only works when the TAS is 60 kt.
- 5° divides TAS by wind speed (100 ÷ 20). The drift grows with the wind, so the wind speed belongs on top.
- 6° halves the result as if the wind were only 30° off the track. Here it blows at 90°, so you get the full maximum drift.
Tip. For a wind at an angle, take a fraction of the maximum drift with the clock rule from the crosswind article: 30° off gives about half, 45° about three quarters, 60° or more almost all of it.
Question 7 of 8
Track error with the 1 in 60 rule
40 NM after the turning point you fix your position 4 NM left of the planned track. What is your track error?
Explanation
The 1 in 60 rule says that 1 NM off track after 60 NM flown is a track error (TE) of 1°. Scale it to the distance you have actually flown: the same 4 NM off after only 40 NM is a bigger angle than after 60 NM.
Step by step
- Distance off track: 4 NM. Distance flown since the turning point: 40 NM.
- TE = 4 × 60 ÷ 40 = 6°.
- You are left of track, so the error is 6° to the left.
Why not the other answers
- 10° divides the distance gone by the distance off (40 ÷ 4). The 1 in 60 rule needs 60 on top.
- 4° takes the nautical miles off track as degrees. That would only be true after exactly 60 NM.
- The angle is right but the side is not: you are left of the planned track.
Tip. The rule holds well up to about 20°, which covers every track error you should meet on a VFR navigation exercise.
Question 8 of 8
Closing angle: heading for the next turning point
You are 4 NM left of track after 40 NM, with 80 NM still to go to the next turning point. By how much, and which way, do you alter heading to fly straight to it?
Explanation
The correction has two parts. The track error (TE) stops you drifting further off; the closing angle (CA) then points you at the turning point. ΔHDG is the change of heading. Both come from the 1 in 60 rule, one with the distance gone and one with the distance to go.
Step by step
- Track error: 4 × 60 ÷ 40 = 6°. Turning 6° right makes you fly parallel to the planned track.
- Closing angle: 4 × 60 ÷ 80 = 3°. Another 3° right closes the 4 NM by the turning point.
- Total: 6° + 3° = 9° to the right, towards the planned track.
Why not the other answers
- 6° right only cancels the track error. You would fly parallel to the track and pass the turning point 4 NM to the left.
- 3° right is only the closing angle. It does not cancel the 6° track error, so you would still pass to the left of the turning point.
- The size is right but the direction is not: you are left of track, so you turn right to get back.
Tip. Write the new heading on your log and note the time. If the closing angle is right, you should see the turning point on the nose at your revised ETA.
Original questions written by FlightDesk Aero and aligned with the EASA syllabus. They are not questions from the official EASA exam bank.