FLC OF AN LGT RESPONDED TO SIMILAR SOUNDING CALL SIGN TO WHICH THE CTLR DID NOT NOTICE THE MISTAKE UNTIL OBSERVING THE WRONG ACFT DSNDING TO HIS CLRNC. THE CTLR DID NOT CATCH THE ERROR AFTER THE FLC CAREFULLY READ BACK THE CLRNC BEFORE STARTING THE DSCNT.

Narrative

ON ARR; APCH CLRED AN ACFT TO 6000 FT AND 210 KTS UPON REACHING. WE WERE FLT ACR X. IT SOUNDED LIKE THE CTLR SAID 'ACR X.' DID NOT NOTICE THIS FLT NUMBER IN PREVIOUS XMISSIONS. AFTER THE CLRNC; NO ONE RESPONDED. I QUERIED THE CTLR IF THE CLRNC TO DSND TO 6000 FT WAS FOR FLT ACR X. HE SAID 'YES; DSND AND MAINTAIN 6000 FT AND SLOW TO 210 KTS.' I READ BACK; 'ACR X; MAINTAIN 6000 FT AND SLOW TO 210 KTS.' AS WE DSNDED PASSING ABOUT 6500 FT THE CTLR SAID 'ACR X; CLB IMMEDIATELY TO MAINTAIN 7000 FT.' IT TURNED OUT THE ORIGINAL CLRNC WAS FOR A FLT SAME NUMBER. I THEN REMARKED AGAIN THAT I HAD VERIFIED THAT CLRNC AND READ BACK AGAIN 'ACR X TO MAINTAIN 6000 FT.' WE WERE IN NO DANGER OF A CONFLICT WHEN THE CTLR CAUGHT HIS ERROR. WE HAD VISUAL OF AN ACFT L TO R AT 6000 FT. SEVERAL LIKE CALL SIGNS DURING A BUSY ARR BANK TIME CAUSED THIS. THIS IS AN ONGOING THREAT TO SAFETY IN THE TERMINAL AREA WITH LIKE CALL SIGNS. AFTER LNDG; I CALLED IAN APCH TO VERIFY WHAT HAD HAPPENED. THE RESPONSE ON THE PHONE WAS 'WE OWE YOU AN APOLOGY' FROM THE SUPVR. THE CTLR DID CLR US INCORRECTLY; NOT REALIZING HE SAID OUR FLT NUMBER. THE CTLR DID REALIZE HIS ERROR AND SUBSEQUENTLY CLRED US BACK TO 7000 FT.