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Resources · VOR & ILS trainer

See how the needles move.

Move the aircraft, turn the OBS and watch the CDI, the TO/FROM flag and the ILS needles respond. Everything runs in your browser; no account needed.

VOR: CDI and TO/FROM

Radial 100 is 10° off the 090 course line, beyond the station: flying the selected course takes you away FROM the station. The needle is full scale left: with a heading close to 090, the course lies to your left, so fly towards the needle.

Turn the heading slider: the needle and flag do not move. A VOR shows where you are relative to the selected course, not which way you are pointing.

Try:
NESWPlan view (north up)
090FROMCDI · 10° full scale, 2° per dotYellow needle: where the selected course is. Top number: the OBS. Box: TO, FROM or OFF.

ILS: localizer and glide slope

On a 3° glide path here
1,274 ft
You are 126 ft above it (+0.30°).
Localizer angle
0.50° right
seen from the localizer antenna at the far end of the runway

Glide slope 2.1 dots down: you are high, fly down towards the needle. Localizer 1.0 dot left: the centreline is to your left, fly towards the needle.

Rule of thumb: a 3° glide path is about 300 ft per NM (318 ft exactly). The closer you get, the more sensitive both needles become.

Try:
LOC · GSLOC 2.5° · GS 0.7° full scaleVertical needle: runway centreline (localizer). Horizontal needle: glide path. Fly towards both; centred means on the approach.

Training aid, not for operational use

This trainer uses an idealised model: no beam bends, no cone of confusion over the station and typical full-scale values (CDI 10°, localizer 2.5°, glide slope 0.7°, 3° glide path, a 3,000 m runway). Real installations differ. Use it to understand the indications for your DGCA Navigation preparation, never for flight.

Test yourself on radio navigation

Practise VOR, ILS, DME and GNSS questions with explanations in the Navigation question bank.

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