If you lose the glideslope on an ILS and you have DME, what is the Missed Approach Point?

• A. Use the DME to identify the MAP
• B. Use the FAF as MAP
• C. Use the outer marker
• D. Use the localizer frequency

Answer: (A)

When the glide slope is unusable, you must still reach the point where a decision to land or go around is made, which is the Missed Approach Point. On an ILS that provides DME, the MAP is defined by a specific DME distance from the localizer/DME facility published on the approach plate. Using the DME readout lets you identify exactly when you’ve reached that MAP, regardless of what you can see visually. The FAF is the starting point of the final approach segment, not the MAP for this scenario, and the outer marker isn’t normally the published MAP on modern ILS procedures. Merely tuning the localizer frequency doesn’t give you the distance to the runway, so it can’t identify the MAP.