Narrative:

During cruise at 14000', ZLA said 'flight X, descend and maintain 11000.' I read back 'descending to 11000' with my call sign, flight X. Upon reaching 11000', center asked for my altitude. I told him 11000' assigned. He said that that was for flight Y. He never mentioned to me a similar sounding call sign and I never heard Y read it back. He never responded to me when I told him flight X. I feel the controller may have used the wrong call sign for the purposed descent clearance. The controller was somewhat busy at the time and seemed a little tired. Also, he never caught my altitude until I had descended the entire 3000'. My copilot also heard him say X, and me say X, on the readback. Supplemental information from acn 135320: the captain and I both agreed that we clearly remember the controller calling X and not Y. After a couple of mins of radio silence the controller asked us to call the ARTCC upon arrival at fat. The remainder of the flight was normal. The captain called our chief pilot first, and then the center. He did not speak directly to the controller who gave us the descent clearance, but was informed that the tapes will be reviewed.

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Original NASA ASRS Text

Title: ANOTHER CASE OF ALT DEVIATION ON CLRNC INTERP OR MISIDENTIFICATION OF ACFT AND THE FLT CREW ACTING ON CLRNC WITHOUT A CONFIRMING REPLY.

Narrative: DURING CRUISE AT 14000', ZLA SAID 'FLT X, DSND AND MAINTAIN 11000.' I READ BACK 'DSNDING TO 11000' WITH MY CALL SIGN, FLT X. UPON REACHING 11000', CENTER ASKED FOR MY ALT. I TOLD HIM 11000' ASSIGNED. HE SAID THAT THAT WAS FOR FLT Y. HE NEVER MENTIONED TO ME A SIMILAR SOUNDING CALL SIGN AND I NEVER HEARD Y READ IT BACK. HE NEVER RESPONDED TO ME WHEN I TOLD HIM FLT X. I FEEL THE CTLR MAY HAVE USED THE WRONG CALL SIGN FOR THE PURPOSED DSCNT CLRNC. THE CTLR WAS SOMEWHAT BUSY AT THE TIME AND SEEMED A LITTLE TIRED. ALSO, HE NEVER CAUGHT MY ALT UNTIL I HAD DSNDED THE ENTIRE 3000'. MY COPLT ALSO HEARD HIM SAY X, AND ME SAY X, ON THE READBACK. SUPPLEMENTAL INFO FROM ACN 135320: THE CAPT AND I BOTH AGREED THAT WE CLEARLY REMEMBER THE CTLR CALLING X AND NOT Y. AFTER A COUPLE OF MINS OF RADIO SILENCE THE CTLR ASKED US TO CALL THE ARTCC UPON ARR AT FAT. THE REMAINDER OF THE FLT WAS NORMAL. THE CAPT CALLED OUR CHIEF PLT FIRST, AND THEN THE CENTER. HE DID NOT SPEAK DIRECTLY TO THE CTLR WHO GAVE US THE DSCNT CLRNC, BUT WAS INFORMED THAT THE TAPES WILL BE REVIEWED.

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.