Narrative:

Approach had cleared me to descend to 3000 ft. My passenger asked me a question and as my attention was diverted I continued my descent through 3000 ft to 2600 ft before I corrected and quickly returned to my assigned altitude. In the future I will brief all my passenger to not engage in conversation with the pilot during critical phases of flight except in an emergency or when they need to convey information helpful to the safety of the flight.

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Original NASA ASRS Text

Title: PLT OF AN SMT TWIN OVERSHOT DSCNT ASSIGNED ALT.

Narrative: APCH HAD CLRED ME TO DSND TO 3000 FT. MY PAX ASKED ME A QUESTION AND AS MY ATTN WAS DIVERTED I CONTINUED MY DSCNT THROUGH 3000 FT TO 2600 FT BEFORE I CORRECTED AND QUICKLY RETURNED TO MY ASSIGNED ALT. IN THE FUTURE I WILL BRIEF ALL MY PAX TO NOT ENGAGE IN CONVERSATION WITH THE PLT DURING CRITICAL PHASES OF FLT EXCEPT IN AN EMER OR WHEN THEY NEED TO CONVEY INFO HELPFUL TO THE SAFETY OF THE FLT.

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.