Narrative:

Detroit approach vectoring us over det to 7d2 for visual approach. Cleared to descend to 3000 ft MSL. Failed to arm autoplt altitude hold mode. Had descended to 2200 ft before recognition. Approach advised at same time. Pilot just back from 2 week vacation, and not good situational awareness. Controller said 'no problem.'

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Original NASA ASRS Text

Title: A CPR PIC ALLOWS HIS ACFT TO DSND OUT OF HIS ASSIGNED ALT WHEN FAILING TO ENGAGE THE ALT HOLD ON THE AUTOPLT 7 MI E OF DET, MI.

Narrative: DETROIT APCH VECTORING US OVER DET TO 7D2 FOR VISUAL APCH. CLRED TO DSND TO 3000 FT MSL. FAILED TO ARM AUTOPLT ALT HOLD MODE. HAD DSNDED TO 2200 FT BEFORE RECOGNITION. APCH ADVISED AT SAME TIME. PLT JUST BACK FROM 2 WK VACATION, AND NOT GOOD SITUATIONAL AWARENESS. CTLR SAID 'NO PROB.'

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.