Navigation — PPL(A)

VFR navigation uses 1:500,000 ICAO aeronautical charts (half-mil) for route planning and 1:250,000 for local area detail. The chart shows controlled airspace, danger areas, mandatory frequency zones, elevation, and prominent landmarks.

• MATZ, ATZ, CTR, TMA — identify the lateral and vertical limits before planning.
• Prominent features: railways, motorways, coastlines, lakes, towns, church spires.
• Avoid planning legs that put you inside controlled airspace without a clearance.
• Always check for temporary restrictions in NOTAMs after the chart date.

True North (from chart), Magnetic North (compass), and Compass North (after deviation) are three different things. The exam tests your ability to convert between them in the correct order.

Memory aid: TVMDC — True, Variation, Magnetic, Deviation, Compass. Apply variation to go from True to Magnetic; apply deviation to go from Magnetic to Compass. East variation is subtracted going to magnetic; west variation is added ("West is best, East is least").

Dead reckoning is navigation by calculation: you know your starting position, your true airspeed, your heading, and the wind velocity. From these you calculate your track over the ground and your groundspeed.

• Track: the path you actually travel over the ground.
• Heading: the direction the nose of the aircraft points.
• Wind drift: the angular difference between track and heading caused by wind.
• Groundspeed: your true airspeed ± wind component. Headwind reduces it, tailwind increases it.

The 1-in-60 rule: 1° of drift causes 1 nm of track error for every 60 nm flown. To correct back to track at the next waypoint, double the correction angle for the remaining distance.

A VOR (VHF Omnidirectional Range) transmits 360 radials from the station. Each radial is a magnetic bearing FROM the station. The CDI (Course Deviation Indicator) shows whether you are left or right of the selected course.

• Select the desired radial on the OBS (Omni Bearing Selector).
• TO/FROM flag: TO = flying towards the station on that bearing, FROM = flying away.
• CDI deflects towards the selected course — fly towards the needle to intercept.
• Station passage: TO/FROM flag flickers or reverses, needle activity increases.
• Cone of confusion: brief period of unreliable indication directly over the station.

An NDB (Non-Directional Beacon) transmits on LF/MF. The ADF (Automatic Direction Finder) needle always points TO the station. Unlike the VOR, you have to apply the relative bearing to your heading to get a magnetic bearing.

• QDM: magnetic heading TO steer to the station in zero wind.
• QDR: magnetic bearing FROM the station (reciprocal of QDM).
• QUJ: true bearing TO the station.
• QTE: true bearing FROM the station.
• Relative bearing: angle between aircraft nose and the direction of the NDB.

If uncertain of position, act methodically. Panic wastes fuel and time. A structured DODAR approach works well: Diagnose, Options, Decide, Act, Review.

• Climb: increase range of visual landmarks and radio reception.
• Circle: stop the drift, maintain a known point if one is visible.
• Confess: declare uncertainty on the radio — ATC and approach radar can help.
• Conserve: do not reduce fuel critically while sorting out position.
• Squawk 7700 (emergency), 7600 (radio failure), 7500 (unlawful interference) if appropriate.
• Request QDM from any unit — they can give you a homing bearing.