What is an ILS approach?
An ILS (Instrument Landing System) gives pilots precision guidance for landing in poor visibility. Two radio beams guide the aircraft: one for lateral alignment (localizer) and one for vertical descent (glideslope).
Components
Localizer - a radio beam aligned with the runway centerline. Tells the pilot if they're left or right of center.
Glideslope - a radio beam angled at about 3 degrees from the runway threshold. Tells the pilot if they're too high or too low.
Decision height - typically 200ft above the runway. If the pilot can't see the runway at this point, they must go around.
How a controller uses ILS
- Vector the aircraft to intercept the localizer at about a 30-degree angle
- Issue the clearance: "cleared ILS runway 27L approach"
- The aircraft captures the localizer and follows it inbound
- At the glideslope intercept point, the aircraft begins descending
- Hand off to tower: "contact tower"
ILS in radarcontrol.io
Use ils 27L to clear an aircraft for ILS. The aircraft automatically captures the localizer and follows the glideslope. Use twr to hand off to tower, and ga if a go-around is needed.