Narrative:

We were cleared to 2;000 feet from ATC on the approach then cleared for the approach. Glide slope appeared to be working because it was at the correct altitude when it came up. Started to follow it down. We realized that it wasn't working when we saw that we got low and then we started to correct back to our altitude. It was an all-nighter; a little tired by the time we were given clearance to land.if the glide slope is out of service please shut it off so it doesn't lead to another situation like that.

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Original NASA ASRS Text

Title: A319 flight crew reported following an inoperative glide slope and receiving a low altitude alert from Tower.

Narrative: We were cleared to 2;000 feet from ATC on the approach then cleared for the approach. Glide slope appeared to be working because it was at the correct altitude when it came up. Started to follow it down. We realized that it wasn't working when we saw that we got low and then we started to correct back to our altitude. It was an all-nighter; a little tired by the time we were given clearance to land.If the glide slope is out of service please shut it off so it doesn't lead to another situation like that.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.