Narrative:

We were cleared to a 170 degree heading and had just leveled at 11000 ft, the first officer noticed a TA on the TCASII. The traffic was still 1100 ft below our altitude, but I said let's keep an eye on it as we looked outside for the traffic. Within 1 min ATC (slc departure), issued a VFR traffic alert and we told that we were already looking for it. The TCASII TA turned into an RA and we told ATC that we were climbing. He repeated that we were climbing and we confirmed this. Within another min, ATC told us to climb to 12000 ft and we leveled at 12000 ft as the traffic passed off our right wing. Initially the VFR aircraft was off our nose at 12 O'clock position and 1100 ft below us. He climbed to within no more than 500 ft vertically and 3.5 to 4 NM laterally. The rest of the flight was uneventful. The other aircraft appeared to be a cessna 172 or 182. Departure told us that he was 'VFR traffic.' the TCASII system worked well and everyone, except the cessna, did what we were supposed to do when a conflict exists.

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Original NASA ASRS Text

Title: MD90 FLC CLB IN RESPONSE TO A TCASII RA AND SUBSEQUENT CLB INSTRUCTIONS FROM DEP CTLR TO PROVIDE SEPARATION WITH VFR TFC. A CESSNA WAS EVENTUALLY SIGHTED BELOW AND OFF OF THE R WING.

Narrative: WE WERE CLRED TO A 170 DEG HDG AND HAD JUST LEVELED AT 11000 FT, THE FO NOTICED A TA ON THE TCASII. THE TFC WAS STILL 1100 FT BELOW OUR ALT, BUT I SAID LET'S KEEP AN EYE ON IT AS WE LOOKED OUTSIDE FOR THE TFC. WITHIN 1 MIN ATC (SLC DEP), ISSUED A VFR TFC ALERT AND WE TOLD THAT WE WERE ALREADY LOOKING FOR IT. THE TCASII TA TURNED INTO AN RA AND WE TOLD ATC THAT WE WERE CLBING. HE REPEATED THAT WE WERE CLBING AND WE CONFIRMED THIS. WITHIN ANOTHER MIN, ATC TOLD US TO CLB TO 12000 FT AND WE LEVELED AT 12000 FT AS THE TFC PASSED OFF OUR R WING. INITIALLY THE VFR ACFT WAS OFF OUR NOSE AT 12 O'CLOCK POS AND 1100 FT BELOW US. HE CLBED TO WITHIN NO MORE THAN 500 FT VERTLY AND 3.5 TO 4 NM LATERALLY. THE REST OF THE FLT WAS UNEVENTFUL. THE OTHER ACFT APPEARED TO BE A CESSNA 172 OR 182. DEP TOLD US THAT HE WAS 'VFR TFC.' THE TCASII SYS WORKED WELL AND EVERYONE, EXCEPT THE CESSNA, DID WHAT WE WERE SUPPOSED TO DO WHEN A CONFLICT EXISTS.

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.