Narrative:

The PNF (the captain) responded to a clearance to 'descend at pilot's discretion to 5000''. While at 11000', the captain read back the clearance including our flight's call sign. The clearance was received at the normal position in the flight from manhattan, ks to kansas city, mo and we were expecting that clearance. After I had initiated my descent from 11000', the controller queried our altitude (we were then 10300'). After replying '10000'', the controller issued traffic '10000' at 11 O'clock'. We reported traffic in sight and was told to climb to 11000'. The controller then informed us the initial descent clearance was not for us, but for another airplane. The oncoming traffic, I believe it was an mlt small transport, took no evasive action as none was necessary, but filed a report of a near miss. If the controller was only working one frequency, he could have heard our response to the clearance, including our callsign, and could have warned us that it was for another airplane. We responded to the clearance and was not told it was not for us. Supplemental information from acn 139545. Apparently the controller was working two frequencys and my readback was blocked.

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Original NASA ASRS Text

Title: ACR SMT ACCEPTED A DESCENT CLRNC MEANT FOR ANOTHER ACFT AND CONFLICTED WITH A MIL SMT.

Narrative: THE PNF (THE CAPT) RESPONDED TO A CLRNC TO 'DSND AT PLT'S DISCRETION TO 5000''. WHILE AT 11000', THE CAPT READ BACK THE CLRNC INCLUDING OUR FLT'S CALL SIGN. THE CLRNC WAS RECEIVED AT THE NORMAL POS IN THE FLT FROM MANHATTAN, KS TO KANSAS CITY, MO AND WE WERE EXPECTING THAT CLRNC. AFTER I HAD INITIATED MY DSCNT FROM 11000', THE CTLR QUERIED OUR ALT (WE WERE THEN 10300'). AFTER REPLYING '10000'', THE CTLR ISSUED TFC '10000' AT 11 O'CLOCK'. WE RPTED TFC IN SIGHT AND WAS TOLD TO CLB TO 11000'. THE CTLR THEN INFORMED US THE INITIAL DSCNT CLRNC WAS NOT FOR US, BUT FOR ANOTHER AIRPLANE. THE ONCOMING TFC, I BELIEVE IT WAS AN MLT SMT, TOOK NO EVASIVE ACTION AS NONE WAS NECESSARY, BUT FILED A RPT OF A NEAR MISS. IF THE CTLR WAS ONLY WORKING ONE FREQ, HE COULD HAVE HEARD OUR RESPONSE TO THE CLRNC, INCLUDING OUR CALLSIGN, AND COULD HAVE WARNED US THAT IT WAS FOR ANOTHER AIRPLANE. WE RESPONDED TO THE CLRNC AND WAS NOT TOLD IT WAS NOT FOR US. SUPPLEMENTAL INFO FROM ACN 139545. APPARENTLY THE CTLR WAS WORKING TWO FREQS AND MY READBACK WAS BLOCKED.

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.