Narrative:

I misread the altimeter. I was assigned 5000 ft. I thought I was getting ready to level off at 5000 ft and departure asked what altitude I was climbing to. I realized I was at 5700 ft instead of 4700 ft. This altimeter is difficult to tell sometimes what the altitude is, because the 1000 ft indicators are in a window to the left. No excuse. I simply looked at it wrong. I know it is difficult to read, so I should have been more alert. I discovered (realized) I was at the wrong altitude. I immediately descended to 5000 ft.

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Original NASA ASRS Text

Title: ALTIMETER PRESENTATION IS READ INCORRECTLY LEADING TO AN OVERSHOOT OF ALT.

Narrative: I MISREAD THE ALTIMETER. I WAS ASSIGNED 5000 FT. I THOUGHT I WAS GETTING READY TO LEVEL OFF AT 5000 FT AND DEP ASKED WHAT ALT I WAS CLBING TO. I REALIZED I WAS AT 5700 FT INSTEAD OF 4700 FT. THIS ALTIMETER IS DIFFICULT TO TELL SOMETIMES WHAT THE ALT IS, BECAUSE THE 1000 FT INDICATORS ARE IN A WINDOW TO THE L. NO EXCUSE. I SIMPLY LOOKED AT IT WRONG. I KNOW IT IS DIFFICULT TO READ, SO I SHOULD HAVE BEEN MORE ALERT. I DISCOVERED (REALIZED) I WAS AT THE WRONG ALT. I IMMEDIATELY DSNDED TO 5000 FT.

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.