Narrative:

Aircraft air carrier cha was talking to approach control it seemed as if approach was talking to aircraft on more than one frequency. We were at 10000' and the controller came on and said no numbers just 'descend to 7000' and contact approach on 125.15' so I repeated the instructions along with my callsign, company cha. We began our descent and started switching frequencys when another voice came on the radio (supervisor?) saying no cha remain this frequency (never for us to maintain altitude). At this point we were at 9300' and no one ever told us to maintain altitude. So when we realized there may have been a mixup, we climbed back to 10000' and awaited further instructions. The problem definitely was the controller monitoring numerous frequencys and not being clear as to which aircraft he was giving instructions to.

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Original NASA ASRS Text

Title: ACR LGT ALT DEVIATION EXCURSION FROM CLRNC ALT IN RESPONSE TO WRONG CALLSIGN.

Narrative: ACFT ACR CHA WAS TALKING TO APCH CTL IT SEEMED AS IF APCH WAS TALKING TO ACFT ON MORE THAN ONE FREQ. WE WERE AT 10000' AND THE CTLR CAME ON AND SAID NO NUMBERS JUST 'DSND TO 7000' AND CONTACT APCH ON 125.15' SO I REPEATED THE INSTRUCTIONS ALONG WITH MY CALLSIGN, COMPANY CHA. WE BEGAN OUR DSNT AND STARTED SWITCHING FREQS WHEN ANOTHER VOICE CAME ON THE RADIO (SUPVR?) SAYING NO CHA REMAIN THIS FREQ (NEVER FOR US TO MAINTAIN ALT). AT THIS POINT WE WERE AT 9300' AND NO ONE EVER TOLD US TO MAINTAIN ALT. SO WHEN WE REALIZED THERE MAY HAVE BEEN A MIXUP, WE CLBED BACK TO 10000' AND AWAITED FURTHER INSTRUCTIONS. THE PROB DEFINITELY WAS THE CTLR MONITORING NUMEROUS FREQS AND NOT BEING CLR AS TO WHICH ACFT HE WAS GIVING INSTRUCTIONS TO.

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.