Narrative:

We were in a cruise descent, descending out of 12000 ft for 9000 ft. I was giving IOE to a new first officer, at the time he was asking a question and on the radio, center was giving holds at our destination. I guess I just got distracted and we descended to 8700 ft. At the time we were on our 5TH leg with 3 more to go. Also it was our 3RD day on duty and sometimes our worst enemy is complacency and fatigue.

Google
 

Original NASA ASRS Text

Title: ALTDEV ALT OVERSHOT IN DSCNT.

Narrative: WE WERE IN A CRUISE DSCNT, DSNDING OUT OF 12000 FT FOR 9000 FT. I WAS GIVING IOE TO A NEW FO, AT THE TIME HE WAS ASKING A QUESTION AND ON THE RADIO, CTR WAS GIVING HOLDS AT OUR DEST. I GUESS I JUST GOT DISTRACTED AND WE DSNDED TO 8700 FT. AT THE TIME WE WERE ON OUR 5TH LEG WITH 3 MORE TO GO. ALSO IT WAS OUR 3RD DAY ON DUTY AND SOMETIMES OUR WORST ENEMY IS COMPLACENCY AND FATIGUE.

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.