Navigation – General Navigation
General Navigation tests chart work, magnetism, the wind triangle, time and fuel-distance calculations. The exam expects clean arithmetic and correct sign handling.
Charts and magnetism
- Use the chart scale for distance and the meridian for direction. Variation is the angle between true and magnetic north; deviation is the aircraft compass error.
- East variation: magnetic heading is true heading minus variation. West variation: add it.
- Compass deviation is applied in the same sign convention as variation; check the compass correction card.
Wind triangle
- Track is the path over the ground; heading is where the nose points. Drift is the angle between them. Apply wind correction into the wind.
- Groundspeed = distance/time. Fuel = flow rate × time.
Worked example
True course 090°, variation 6°E, deviation 2°E, forecast drift 10° right. Magnetic heading = 090 − 6 = 084°. Compass heading = 084 − 2 = 082°. To counter 10° right drift, steer 082 − 10 = 072° compass. If groundspeed is 120 kt over 60 NM, time = 30 min.
Traps
Adding east variation instead of subtracting; applying deviation to the true course; confusing drift with heading change; using airspeed instead of groundspeed for time; forgetting that wind direction is given from, not to.