Narrative:

I was working the low altitude sector at ZZZ and two aircraft were handed off to me with similar sounding call signs. Aircraft X; abbc and aircraft Y; abcd; which didn't look similar but when stated out loud do sound alike. I issued a control instruction to descend to 4000 ft and fly heading 110 degrees to aircraft X; abbc that was followed by aircraft Y; abcd. Approach had given me the two aircraft and noticed right away that aircraft Y; abcd; was descending and called to effect coordination. There were no aircraft near aircraft Y; abcd; and no separation was lost.

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Original NASA ASRS Text

Title: APPROACH CONTROLLER DESCRIBED UNEXPECTED DESCENT EVENT INVOLVING SIMILAR SOUNDING CALL SIGNS WITH FOUR DIGIT FLIGHT NUMBERS; DIFFERENT NUMBERS; BUT WHEN CALLED; SOUNDED THE SAME.

Narrative: I WAS WORKING THE LOW ALTITUDE SECTOR AT ZZZ AND TWO ACFT WERE HANDED OFF TO ME WITH SIMILAR SOUNDING CALL SIGNS. ACFT X; ABBC AND ACFT Y; ABCD; WHICH DIDN'T LOOK SIMILAR BUT WHEN STATED OUT LOUD DO SOUND ALIKE. I ISSUED A CONTROL INSTRUCTION TO DESCEND TO 4000 FT AND FLY HEADING 110 DEGS TO ACFT X; ABBC THAT WAS FOLLOWED BY ACFT Y; ABCD. APPROACH HAD GIVEN ME THE TWO ACFT AND NOTICED RIGHT AWAY THAT ACFT Y; ABCD; WAS DESCENDING AND CALLED TO EFFECT COORDINATION. THERE WERE NO AIRCRAFT NEAR ACFT Y; ABCD; AND NO SEPARATION WAS LOST.

Data retrieved from NASA's ASRS site as of May 2009 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.