Narrative:

We were assigned 12,000 by burbank approach. We were above 10,000. I was making a notation on the flight log when I looked up. We were passing through 13,500. I quickly reminded my first officer that we were supposed to be at 12,000. Approach told us to stop our climb. We did. He came back a few seconds later and cleared us to 14,000. He reminded us our assigned altitude was 12,000 and gave us center frequency. I apologized and switched to center. The problem arose due to both of us being inattentive to the altitude.

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Original NASA ASRS Text

Title: COMMUTER FLT CREW GUILTY OF 1500' ALT BUST.

Narrative: WE WERE ASSIGNED 12,000 BY BURBANK APCH. WE WERE ABOVE 10,000. I WAS MAKING A NOTATION ON THE FLT LOG WHEN I LOOKED UP. WE WERE PASSING THROUGH 13,500. I QUICKLY REMINDED MY F/O THAT WE WERE SUPPOSED TO BE AT 12,000. APCH TOLD US TO STOP OUR CLIMB. WE DID. HE CAME BACK A FEW SECONDS LATER AND CLRED US TO 14,000. HE REMINDED US OUR ASSIGNED ALT WAS 12,000 AND GAVE US CENTER FREQ. I APOLOGIZED AND SWITCHED TO CENTER. THE PROBLEM AROSE DUE TO BOTH OF US BEING INATTENTIVE TO THE ALT.

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.