ALTDEV ALT EXCURSION. AN ACR RECEIVES A TCASII RA AND CLBS OUT OF DANGER THEN RETURNS TO ITS ORIGINAL ALT AND COURSE.

Narrative

WE WERE LEVEL AT 11000 FT WHEN WE RECEIVED A TA FROM TCASII. TFC WAS AT 12 O'CLOCK 10600 FT AND CLBING. I SAW HIM VISUALLY AND NOTICED A DEFINITE R TO L MOVEMENT. AS HE REACHED 11000 FT WE GOT THE RA 'DSND' (1 TIME) FOLLOWED BY A COMMAND THAT I MISSED; THEN 'CLB; CLB NOW; CLB; CLB NOW.' THE FO TURNED OFF THE AUTOPLT; AND FOLLOWED THE RA GUIDANCE. AT 11600 FT THE TCASII GAVE A 'CLR OF CONFLICT' AND WE RETURNED TO 11000 FT. NOTIFIED APCH CTL OF THE ALTDEV. APCH SAID THAT PERHAPS THEY SHOULD HAVE MENTIONED THE TFC. HE WAS VFR; BUT APCH APPARENTLY KNEW HE WAS THERE. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE CTLR KNEW OF THE LIGHT ACFT'S PRESENCE PRIOR TO THE FLC GETTING THE TCASII RA; BUT FOR SOME REASON DID NOT TELL THEM ABOUT IT. THE CAPT SAID THAT HE WATCHED THE TCASII AS THE ACFT'S RETURN SHOWED THAT HE WAS CLBING AND SAW THAT IT WAS GOING TO INTRUDE INTO THEIR AREA. HE SAID TO THE FO THAT HE SHOULD GET READY FOR A WARNING. THE FIRST WARNING WAS AN RA. THE RPTR SAID THAT HE HAS RECEIVED SEVERAL TCASII WARNINGS AND THEY HAVE ALL BEEN ACCURATE. THE OTHER ACFT WAS A HIGH WING SINGLE ENG ACFT; BUT THE CAPT DID NOT HAVE FURTHER INFO.