Narrative:

Level at FL230, I heard the last part of a transmission from center to us, telling us to descend to 16000'. Not knowing for sure, we paused for a few seconds. Replied to center '16000 flight xyz (our flight #).' center came back to flight xyz to descend 16000' I thought he was repeating a clearance to flight xyp. We remained at FL230 until center asked us what our altitude was. Then I knew I had missed the clearance to descend. We replied to center we were descending to 16000'. Monitor frequency, and if a questions is present in a clearance, ask.

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Original NASA ASRS Text

Title: CALL SIGN CONFUSION FOR ARTCC CTLR AND COMMUTER MDT FLT CREW IN ALT ASSIGNMENT.

Narrative: LEVEL AT FL230, I HEARD THE LAST PART OF A XMISSION FROM CENTER TO US, TELLING US TO DSND TO 16000'. NOT KNOWING FOR SURE, WE PAUSED FOR A FEW SECS. REPLIED TO CENTER '16000 FLT XYZ (OUR FLT #).' CENTER CAME BACK TO FLT XYZ TO DSND 16000' I THOUGHT HE WAS REPEATING A CLRNC TO FLT XYP. WE REMAINED AT FL230 UNTIL CENTER ASKED US WHAT OUR ALT WAS. THEN I KNEW I HAD MISSED THE CLRNC TO DSND. WE REPLIED TO CENTER WE WERE DSNDING TO 16000'. MONITOR FREQ, AND IF A QUESTIONS IS PRESENT IN A CLRNC, ASK.

Data retrieved from NASA's ASRS site as of August 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.