NDB/ADF and VOR
10 min read
NDB and ADF
An NDB transmits in all directions (roughly 190–1,750 kHz); the aircraft's ADF points at it and shows the relative bearing. QDM = magnetic heading + relative bearing.
Errors: night effect (sky waves mix in, especially around dusk and dawn), thunderstorms (the needle may point at a CB), coastal refraction (bending as the wave crosses the coast at an angle), mountain effect and quadrantal error from the airframe. Identify by its Morse code; many receivers give no failure flag.
IN THIS LESSON
- VOR
- DME
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