Which component provides vertical guidance in an ILS approach?

Which component provides vertical guidance in an ILS approach?

• A. Glideslope
• B. Localizer
• C. Outer marker
• D. DME

Answer: (A)

Vertical guidance in an ILS approach comes from the glideslope. The glideslope transmitter near the runway creates a defined glide path, typically about a 3-degree descent. Your cockpit instruments show deviation from this path, telling you whether you’re above or below the proper slope and by how much. Following the glideslope keeps you on a steady descent to the runway. The localizer, by contrast, provides horizontal guidance to keep you aligned with the runway centerline. The outer marker is a fixed distance reference along the approach, not a guidance cue for vertical descent, and DME gives distance information rather than vertical position.

Vertical guidance in an ILS approach comes from the glideslope. The glideslope transmitter near the runway creates a defined glide path, typically about a 3-degree descent. Your cockpit instruments show deviation from this path, telling you whether you’re above or below the proper slope and by how much. Following the glideslope keeps you on a steady descent to the runway.

The localizer, by contrast, provides horizontal guidance to keep you aligned with the runway centerline. The outer marker is a fixed distance reference along the approach, not a guidance cue for vertical descent, and DME gives distance information rather than vertical position.