Narrative:

Received information from ATIS. Set on right side altimeter, but failed to set on left side until approach asked why I was 600 ft high. No known conflict as a result. Just felt stupid. I normally set altimeter at FL180, but was distracted by a faulty anti-ice system.

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Original NASA ASRS Text

Title: PLT OF A SINGLE PLT CESSNA CITATION 501 FORGOT TO RESET THE ALTIMETER IN FRONT OF HIM WHEN DSNDING THROUGH FL180 DUE TO AN ANTI-ICE SYS PROB CAUSING ATC INTERVENTION TO ALERT HIM THAT HE WAS 600 FT HIGH.

Narrative: RECEIVED INFO FROM ATIS. SET ON R SIDE ALTIMETER, BUT FAILED TO SET ON L SIDE UNTIL APCH ASKED WHY I WAS 600 FT HIGH. NO KNOWN CONFLICT AS A RESULT. JUST FELT STUPID. I NORMALLY SET ALTIMETER AT FL180, BUT WAS DISTRACTED BY A FAULTY ANTI-ICE SYS.

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.