Narrative:

Significant weather in the area and multiple deviations; [I was] working two fixes; zzzzz and xxxxx both deviating around weather areas. A CRJ2 jet [was] at 110 from xxxxx and a SF34 [was] at 090 from xxxxx. The SF34 from zzzzz [was] also on the same frequency. There were multiple coordinations regarding the deviations and crossovers for the weather. I had handed the two xxxxx aircraft off to the south feeder as they would crossover but had not shipped the CRJ2 yet because we hadn't decided on his runway yet and I was still thinking to change the data tag. Meanwhile I was amending altitudes of the zzzzz traffic as they had started to deviate on different headings. I issued a descent to what I thought was the SF34 (zzzzz fix) to 7;000. I used the wrong call sign; that of the CRJ2. When I went back to change altitude for the SF34 and heard the CRJ2 read back I saw the aircraft descending through 10;600 and I issued 10;000 and issued the 9;000 traffic. The data tag showed 9;700 before climbing back to 10;000. I did not warn the aircraft of the similar sounding call signs. That may have also saved me from using the wrong call sign. I also should have shipped the CRJ2 to the south feeder controller and let them decide which runway to go to and take care of the data tag. The plane was going to his airspace anyway and that controller was not dealing with all the deviations. I got tunnel vision with that one plane that still needed things to be done and that is why I think I used his call sign.

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Original NASA ASRS Text

Title: TRACON Controller experienced a loss of separation when providing multiple weather avoidance vectors to aircraft with similar sounding callsigns; the reporter acknowledging that no warnings were issued to the involved flights.

Narrative: Significant weather in the area and multiple deviations; [I was] working two fixes; ZZZZZ and XXXXX both deviating around weather areas. A CRJ2 jet [was] at 110 from XXXXX and a SF34 [was] at 090 from XXXXX. The SF34 from ZZZZZ [was] also on the same frequency. There were multiple coordinations regarding the deviations and crossovers for the weather. I had handed the two XXXXX aircraft off to the South Feeder as they would crossover but had not shipped the CRJ2 yet because we hadn't decided on his runway yet and I was still thinking to change the data tag. Meanwhile I was amending altitudes of the ZZZZZ traffic as they had started to deviate on different headings. I issued a descent to what I thought was the SF34 (ZZZZZ fix) to 7;000. I used the wrong call sign; that of the CRJ2. When I went back to change altitude for the SF34 and heard the CRJ2 read back I saw the aircraft descending through 10;600 and I issued 10;000 and issued the 9;000 traffic. The data tag showed 9;700 before climbing back to 10;000. I did not warn the aircraft of the similar sounding call signs. That may have also saved me from using the wrong call sign. I also should have shipped the CRJ2 to the South Feeder Controller and let them decide which runway to go to and take care of the data tag. The plane was going to his airspace anyway and that controller was not dealing with all the deviations. I got tunnel vision with that one plane that still needed things to be done and that is why I think I used his call sign.

Data retrieved from NASA's ASRS site as of April 2012 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.