Narrative:

During ILS approach to vny 16R tower advised of a low altitude alert, just as I was breaking out of the clouds. I scanned everything only to find an off flag on the glide slope. I leveled off and only began descent when the runway and VASI became visible. There was much turbulence and rain and I never noticed the problem. I landed uneventfully. The next time it appears I am flying a perfect ILS glide slope in rain and turbulence, I will start looking around.

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Original NASA ASRS Text

Title: SMA DROPPED BELOW GLIDE SLOPE DURING ILS APCH. GOT LOW ALT ALERT.

Narrative: DURING ILS APCH TO VNY 16R TWR ADVISED OF A LOW ALT ALERT, JUST AS I WAS BREAKING OUT OF THE CLOUDS. I SCANNED EVERYTHING ONLY TO FIND AN OFF FLAG ON THE GLIDE SLOPE. I LEVELED OFF AND ONLY BEGAN DSNT WHEN THE RWY AND VASI BECAME VISIBLE. THERE WAS MUCH TURBULENCE AND RAIN AND I NEVER NOTICED THE PROBLEM. I LANDED UNEVENTFULLY. THE NEXT TIME IT APPEARS I AM FLYING A PERFECT ILS GLIDE SLOPE IN RAIN AND TURBULENCE, I WILL START LOOKING AROUND.

Data retrieved from NASA's ASRS site as of July 2007 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.