FAA Instrument Rating Airplane (IRA)Navigation SystemsEasy
Which of the following is a component of an Instrument Landing System (ILS) that provides lateral guidance to the runway centerline?
- ADME
- BLocalizer
- CGlide slope
- DMarker beacon
Show answer & explanationAnswer & explanation
Correct answer: B. Localizer
The localizer component of an ILS provides lateral guidance, aligning the aircraft with the runway centerline. The glide slope provides vertical guidance, and marker beacons provide range information.
Why the other options are wrong
- A. DME (Distance Measuring Equipment) provides slant-range distance, not lateral guidance for an ILS.
- C. The glide slope provides vertical guidance, not lateral.
- D. Marker beacons provide range information along the approach path, not lateral guidance.
ILS Components
An Instrument Landing System (ILS) consists of several ground-based components that provide precision guidance for aircraft during approach and landing.
- Localizer: lateral guidance (runway centerline).
- Glide Slope: vertical guidance (descent path).
- Marker Beacons: range information (distance from touchdown).
- DME (optional): provides continuous distance to the runway threshold.
Memory trick: LGMD: Localizer, Glide slope, Marker beacons, DME.