Which statement best describes Inner Marker (IM) signaling on an instrument approach?

Which statement best describes Inner Marker (IM) signaling on an instrument approach?

• A. Outer Marker is the only marker used anymore.
• B. Middle Marker serves as the final approach fix.
• C. Inner Marker is not used in any modern approach.
• D. Inner Marker provides an audio/visual cue at a precise position on the approach with a distinct signal.

Answer: (D)

Inner Marker signaling on an instrument approach is a marker beacon that provides a precise position cue along the ILS approach, with both an audible signal and a visual indicator. It uses a distinct, high-frequency tone (and a white marker light) to tell you you’re at a specific point near the runway—typically near the threshold—and it’s especially useful for high-precision approaches such as CAT II/III. This cue helps confirm your exact location on the final approach, beyond what the outer and middle markers provide, and it remains a feature only where the approach includes an inner marker.

Inner Marker signaling on an instrument approach is a marker beacon that provides a precise position cue along the ILS approach, with both an audible signal and a visual indicator. It uses a distinct, high-frequency tone (and a white marker light) to tell you you’re at a specific point near the runway—typically near the threshold—and it’s especially useful for high-precision approaches such as CAT II/III. This cue helps confirm your exact location on the final approach, beyond what the outer and middle markers provide, and it remains a feature only where the approach includes an inner marker.