ACR DH8 FLC AT FL220 REACTS TO TCASII RA ACTIVATED CLB COMMAND CAUSED BY RAPIDLY CLBING TFC FROM BELOW. THE TCASII EVASIVE MANEUVER CAUSES THE DH8 FLC TO CLB INTO PROX TO OTHER XING TFC AT FL230.

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A FASTER ACFT Y AT OUR 4 O'CLOCK POS WAS CLBING FROM BELOW US. WE GOT THE FOLLOWING TCASII ANNOUNCEMENTS: TFC; MONITOR VERT SPD; CLB; CLB NOW; XING CLB; CLR OF CONFLICT. TCASII WAS SET OFF BY A CLBING AND FASTER TFC (SAME DIRECTION) AT OUR 4 O'CLOCK POS. WE CLBED TO FL225 AND TFC WAS 900 FT BELOW US. WE STOPPED OUR CLB AT FL275 BECAUSE OF OPPOSITE DIRECTION TFC Z AT FL230. I WAS CLR AND WE HAD BOTH ACFT IN SIGHT. WHEN THE TCASII TOLD US TO CLB; IT REQUESTED 2500 FPM. THEN AS WE CONVERGED ON FL225 AND WE SAW THAT THE TFC BELOW US HAD LEVELED OFF; WE DID THE SAME; AND NOTICED THAT OUR VSI TCASII WAS COMPLETELY RED (NO CLB OR DSND INDICATION) AND WE DECIDED TO TURN R TO VEER AWAY FROM BOTH THE ABOVE AND BELOW TFC. AS WE TURNED; ATC TOLD US TO MAINTAIN FL220. THEN WE GOT 'CLR OF CONFLICT' AND WE TOLD ATC THAT THE ACFT BELOW US TRIGGERED THE TCASII TO WHICH WE RESPONDED; AND HE WAS SURPRISED WHEN HE ASKED US IF WE GOT ANY TCASII RA FROM THE TFC ABOVE; AND TO WHICH WE SAID NO. I THINK INITIALLY; THE TCASII PROBABLY WANTED US TO CLB THROUGH THE ABOVE ACFT'S ALT; BUT HE LOOKED CLOSE AND WE LEVELED OFF AT FL225 AND THE TCASII PROBABLY RAN OUT OF OPTIONS AND WENT ALL RED.