Narrative:

VMC, airport in sight, told 'cleared for the visual to runway 2, maintain 3000 ft until turning base.' PF (captain) called for the runway centerline to be extended. I did this, but when I looked up, he was already down to 2700 ft and still descending. I repeated the clearance to him and he leveled off, but would not return to the assigned altitude. A min or two later, we turned base.

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Original NASA ASRS Text

Title: B757 FO COACHES CAPT TO COMPLY WITH ATC VISUAL APCH CLRNC, TO HOLD ALT UNTIL BASE LEG, BUT CAPT BEGINS DSCNT ANYWAY. FO FINALLY GETS CAPT TO LEVEL OFF ON BASE LEG.

Narrative: VMC, ARPT IN SIGHT, TOLD 'CLRED FOR THE VISUAL TO RWY 2, MAINTAIN 3000 FT UNTIL TURNING BASE.' PF (CAPT) CALLED FOR THE RWY CTRLINE TO BE EXTENDED. I DID THIS, BUT WHEN I LOOKED UP, HE WAS ALREADY DOWN TO 2700 FT AND STILL DSNDING. I REPEATED THE CLRNC TO HIM AND HE LEVELED OFF, BUT WOULD NOT RETURN TO THE ASSIGNED ALT. A MIN OR TWO LATER, WE TURNED BASE.

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.