Narrative:

Due to missetting of altimeter the actual flight may have been lower than 1000' AGL. Corrective action: as a xchk, confirm approximately altimeter setting with ATIS off of O'hare and dupage. It is common to set altimeter to field elevation on the ground before takeoff. Now a xchk with ATIS information will help confirm correct setting.

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Original NASA ASRS Text

Title: POSSIBLE VIOLATION OF FARS IN LOW ALT CIVIL OPERATION BY BANNER TOW ACFT AS HE USES IMPROPER ALT SETTING PROC AND MAY HAVE OVERFLOWN A POPULATED AREA AT LESS THAN 1000'.

Narrative: DUE TO MISSETTING OF ALTIMETER THE ACTUAL FLT MAY HAVE BEEN LOWER THAN 1000' AGL. CORRECTIVE ACTION: AS A XCHK, CONFIRM APPROX ALTIMETER SETTING WITH ATIS OFF OF O'HARE AND DUPAGE. IT IS COMMON TO SET ALTIMETER TO FIELD ELEVATION ON THE GND BEFORE TKOF. NOW A XCHK WITH ATIS INFO WILL HELP CONFIRM CORRECT SETTING.

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.