Narrative:

Flying GPS/lpv runway 13. Misread approach chart and saw alt from if to FAF as 2000 ft. Rather than charted 2400 ft. Approaching FAF tower informed me I was indicating 2000 ft. Rather than 2400 ft. Shortly before this at about 2250 ft.; avidyne ifd 440 had given me a yellow low altitude warning; but I assumed it was in error. Did not get a terrain warning since I remained at least 1200 ft. Above terrain/obstacles below or ahead of me. I was tired and too comfortable flying into my home field though it was an approach I had not flown before. I should not have assumed the low altitude warning was an error; and instead rechecked the approach chart immediately. I held 2000 ft. Till intercepting the gp (glide path).

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Original NASA ASRS Text

Title: PA-31 pilot reported descending below the published altitude during a GPS approach due to misreading the chart.

Narrative: Flying GPS/LPV RWY 13. Misread approach chart and saw alt from IF to FAF as 2000 ft. rather than charted 2400 ft. Approaching FAF tower informed me I was indicating 2000 ft. rather than 2400 ft. Shortly before this at about 2250 ft.; Avidyne IFD 440 had given me a yellow low altitude warning; but I assumed it was in error. Did not get a terrain warning since I remained at least 1200 ft. above terrain/obstacles below or ahead of me. I was tired and too comfortable flying into my home field though it was an approach I had not flown before. I should not have assumed the low altitude warning was an error; and instead rechecked the approach chart immediately. I held 2000 ft. till intercepting the GP (Glide Path).

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.