Narrative:

Traffic was heavy at the time with numerous VFR call-ups and itinerant aircraft. I had just relieved the previous controller (5 mins) when the loss of separation occurred. Controller being relieved began a hasty briefing when I was on the other side of the room attempting to get my headset on. This was complicated by the fact that aircraft were calling while he was giving the briefing. On the electronic terminal voice switching system. This automatically puts the pilot's voice in speaker (while briefing button is depressed). Due to location on the speaker, the pilot's voice comes through the controller's boom on his headset as he is speaking, garbling everything said. The controller being relieved immediately left the room and I was not able to ask him any questions about traffic. Commuter aircraft X was IFR sbound climbing to 100 ft. I turned him east to join airway -- ZOB had handoff. BE58 (aircraft Y) was nwbound at 10000 ft on route. VFR (aircraft Z) aircraft called me inbound to roc. I saw conflict with commuter and BE58 and attempted twice to get a higher altitude for the commuter aircraft -- to separate from the BE58. Each time I tried, the same VFR aircraft kept calling me. I did get the higher altitude (14000 ft) from ZOB, but became distraction by the VFR aircraft. I apparently had that VFR aircraft's call sign on the brain because I issued it to the wrong aircraft (the VFR) who read it back and never questioned it until about 2 mins later (VFR aircraft was at 3000 ft). In my mind, I heard the reply for the clearance and had thought it came from the commuter. BE58 and SF34 were 10 mi apart on converging courses, both at 10000 ft when clearance was issued, but I knew I would have altitude separation before they would conflict with each other. When I noticed the SF34 was not climbing, I issued traffic to both aircraft and turned both of them to avoid each other. SF34 said he was descending for an RA -- separation was lost, 500 ft vertical, 1.61 NM lateral. Many factors contributed to this error. I was stupid to allow myself to become distraction by the VFR aircraft.

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Original NASA ASRS Text

Title: ROC CTLR TRANSPOSES ACFT CALL SIGN AND CLRNC BTWN AN IFR OUTBOUND SF340, IFR ENRTE BE58 AND A VFR INBOUND, WHICH RESULTS IN A LOSS OF SEPARATION BTWN THE 2 IFR ACFT.

Narrative: TFC WAS HVY AT THE TIME WITH NUMEROUS VFR CALL-UPS AND ITINERANT ACFT. I HAD JUST RELIEVED THE PREVIOUS CTLR (5 MINS) WHEN THE LOSS OF SEPARATION OCCURRED. CTLR BEING RELIEVED BEGAN A HASTY BRIEFING WHEN I WAS ON THE OTHER SIDE OF THE ROOM ATTEMPTING TO GET MY HEADSET ON. THIS WAS COMPLICATED BY THE FACT THAT ACFT WERE CALLING WHILE HE WAS GIVING THE BRIEFING. ON THE ELECTRONIC TERMINAL VOICE SWITCHING SYS. THIS AUTOMATICALLY PUTS THE PLT'S VOICE IN SPEAKER (WHILE BRIEFING BUTTON IS DEPRESSED). DUE TO LOCATION ON THE SPEAKER, THE PLT'S VOICE COMES THROUGH THE CTLR'S BOOM ON HIS HEADSET AS HE IS SPEAKING, GARBLING EVERYTHING SAID. THE CTLR BEING RELIEVED IMMEDIATELY LEFT THE ROOM AND I WAS NOT ABLE TO ASK HIM ANY QUESTIONS ABOUT TFC. COMMUTER ACFT X WAS IFR SBOUND CLBING TO 100 FT. I TURNED HIM E TO JOIN AIRWAY -- ZOB HAD HDOF. BE58 (ACFT Y) WAS NWBOUND AT 10000 FT ON RTE. VFR (ACFT Z) ACFT CALLED ME INBOUND TO ROC. I SAW CONFLICT WITH COMMUTER AND BE58 AND ATTEMPTED TWICE TO GET A HIGHER ALT FOR THE COMMUTER ACFT -- TO SEPARATE FROM THE BE58. EACH TIME I TRIED, THE SAME VFR ACFT KEPT CALLING ME. I DID GET THE HIGHER ALT (14000 FT) FROM ZOB, BUT BECAME DISTR BY THE VFR ACFT. I APPARENTLY HAD THAT VFR ACFT'S CALL SIGN ON THE BRAIN BECAUSE I ISSUED IT TO THE WRONG ACFT (THE VFR) WHO READ IT BACK AND NEVER QUESTIONED IT UNTIL ABOUT 2 MINS LATER (VFR ACFT WAS AT 3000 FT). IN MY MIND, I HEARD THE REPLY FOR THE CLRNC AND HAD THOUGHT IT CAME FROM THE COMMUTER. BE58 AND SF34 WERE 10 MI APART ON CONVERGING COURSES, BOTH AT 10000 FT WHEN CLRNC WAS ISSUED, BUT I KNEW I WOULD HAVE ALT SEPARATION BEFORE THEY WOULD CONFLICT WITH EACH OTHER. WHEN I NOTICED THE SF34 WAS NOT CLBING, I ISSUED TFC TO BOTH ACFT AND TURNED BOTH OF THEM TO AVOID EACH OTHER. SF34 SAID HE WAS DSNDING FOR AN RA -- SEPARATION WAS LOST, 500 FT VERT, 1.61 NM LATERAL. MANY FACTORS CONTRIBUTED TO THIS ERROR. I WAS STUPID TO ALLOW MYSELF TO BECOME DISTR BY THE VFR ACFT.

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.