Narrative:

ATC was working multiple frequencys. En route to iad from lyh, after being cleared direct brv, ATC cleared us from 8000 ft to descend and maintain 6000 ft. First officer (PNF) read back the instruction with no reply from ATC. Captain (reporter and PF) confirmed the instruction and initiated descent. Over 1 min later, while passing through 7000 ft, ATC called us to say the descent had been for another aircraft and to maintain 8000 ft. We immediately began a climb to 8000 ft. Again, captain and first officer confirmed that the previous instruction to descend had been for us, and the call sign of the aircraft that was supposed to descend was different enough from ours that we could not have confused it. No further remark was made by ATC regarding our altitude change.

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Original NASA ASRS Text

Title: A JETSTREAM 32 FLT CREW ACCEPTS A CLRNC THAT WAS MEANT FOR ANOTHER ACFT BUT THEIR CALL SIGN WAS USED BY CTLR USING MULTIPLE FREQS AT RIC, VA.

Narrative: ATC WAS WORKING MULTIPLE FREQS. ENRTE TO IAD FROM LYH, AFTER BEING CLRED DIRECT BRV, ATC CLRED US FROM 8000 FT TO DSND AND MAINTAIN 6000 FT. FO (PNF) READ BACK THE INSTRUCTION WITH NO REPLY FROM ATC. CAPT (RPTR AND PF) CONFIRMED THE INSTRUCTION AND INITIATED DSCNT. OVER 1 MIN LATER, WHILE PASSING THROUGH 7000 FT, ATC CALLED US TO SAY THE DSCNT HAD BEEN FOR ANOTHER ACFT AND TO MAINTAIN 8000 FT. WE IMMEDIATELY BEGAN A CLB TO 8000 FT. AGAIN, CAPT AND FO CONFIRMED THAT THE PREVIOUS INSTRUCTION TO DSND HAD BEEN FOR US, AND THE CALL SIGN OF THE ACFT THAT WAS SUPPOSED TO DSND WAS DIFFERENT ENOUGH FROM OURS THAT WE COULD NOT HAVE CONFUSED IT. NO FURTHER REMARK WAS MADE BY ATC REGARDING OUR ALT CHANGE.

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.