The lateral guidance component of the Instrument Landing System (ILS). The localizer provides precise left/right alignment information to guide the aircraft to the runway centerline during an instrument approach.
Key characteristics:
- Signal: A directional radio beam transmitted along the extended centerline of the runway.
- Coverage: Typically effective up to 18 NM from the runway, within ±10° of the centerline, and up to 4,500 feet AGL.
- Cockpit indication: Shown on the aircraft’s Horizontal Situation Indicator (HSI) or ILS display as a deviation bar/needle that moves left or right.
- Use in approach: Pilots intercept the localizer at a shallow angle, then track it inbound to remain aligned with the runway.
- Integration: Works in tandem with the glideslope (GS) for full ILS precision approaches.
Application in DCS World
- Many DCS aircraft with ILS capability (F/A-18C, F-16C, A-10C, C-101, L-39) can receive localizer signals where implemented, allowing cadets to practice runway alignment in low-visibility conditions.
- Not all runways in DCS maps are equipped with ILS. Additionally, the signal coverage and limitations are simplified compared to real-world systems (e.g., terrain interference not always modeled).
Cadets should practice localizer intercepts, tracking, and corrections in poor visibility, as well as transitions from localizer-only approaches to full ILS when glideslope is available.