On final approach to an ILS, if the glideslope is lost, when should you go missed?

On final approach to an ILS, if the glideslope is lost, when should you go missed?

• A. At the published MAP on the chart
• B. At the point you discover the failure
• C. After you've intercept the localizer again
• D. When you are 2 miles from the runway

Answer: (B)

When an instrument on an approach becomes unreliable, you must go around as soon as you know it’s not functioning. On an ILS, the glide slope provides critical vertical guidance; losing it means you no longer have the required vertical path to the runway, and continuing could put you at risk of an improper descent profile or obstacles. So the safe action is to initiate a missed approach the moment you discover the glide slope failure, rather than waiting to a published MAP, re-intercepting the localizer, or waiting until a fixed distance from the runway.

When an instrument on an approach becomes unreliable, you must go around as soon as you know it’s not functioning. On an ILS, the glide slope provides critical vertical guidance; losing it means you no longer have the required vertical path to the runway, and continuing could put you at risk of an improper descent profile or obstacles. So the safe action is to initiate a missed approach the moment you discover the glide slope failure, rather than waiting to a published MAP, re-intercepting the localizer, or waiting until a fixed distance from the runway.