Narrative:

Air carrier X checked in at 6000 ft. Traffic was observed and issued leaving 5300 ft in a climb opposite direction squawking VFR, at air carrier X's 12 O'clock, 6 mi. I observed the VFR was on a merging heading climbing out of 5500 ft. I issued a turn to air carrier X to miss the VFR target. Air carrier X advised he was receiving a TCASII RA and was responding to it. The closest IFR traffic was at 11000 ft immediately above air carrier X. Air carrier X resumed his original heading and altitude after he went around the traffic. Air carrier X was issued a heading to remain 1 mi clear of the traffic. The climb air carrier X did was unnecessary and excessive.

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Original NASA ASRS Text

Title: ACR X TCASII RA WITH VFR ACFT Y CLBING THROUGH OCCUPIED ALT.

Narrative: ACR X CHKED IN AT 6000 FT. TFC WAS OBSERVED AND ISSUED LEAVING 5300 FT IN A CLB OPPOSITE DIRECTION SQUAWKING VFR, AT ACR X'S 12 O'CLOCK, 6 MI. I OBSERVED THE VFR WAS ON A MERGING HDG CLBING OUT OF 5500 FT. I ISSUED A TURN TO ACR X TO MISS THE VFR TARGET. ACR X ADVISED HE WAS RECEIVING A TCASII RA AND WAS RESPONDING TO IT. THE CLOSEST IFR TFC WAS AT 11000 FT IMMEDIATELY ABOVE ACR X. ACR X RESUMED HIS ORIGINAL HDG AND ALT AFTER HE WENT AROUND THE TFC. ACR X WAS ISSUED A HDG TO REMAIN 1 MI CLR OF THE TFC. THE CLB ACR X DID WAS UNNECESSARY AND EXCESSIVE.

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.