FLC OF AN MLG ACR ACFT CLBED FROM ASSIGNED ALT IN RESPONSE TO A TCASII RA.

Narrative

IN LEVEL CRUISE AT FL220; RECEIVED A TCASII TA ON A CONTACT AT APPROX 4 MI AT 12:30 POS. ABOUT 3 SECONDS LATER; AS TFC CONTINUED TO CLOSE; AN RA WAS ISSUED AS TARGET WAS AT APPROX 3 NM; 1 O'CLOCK POS; APPROX 1400 FT BELOW AND CLBING. RA COMMANDED A 1500 FPM CLB. I PROMPTLY DISCONNECTED THE AUTOPLT AND COMMENCED 1500 FPM CLB WHILE ASKING THE CAPT TO ADVISE CTR THAT WE WERE CLBING IN RESPONSE TO AN RA. WITH THE 1500 FPM CLB ESTABLISHED I SCANNED OUTSIDE TO ACQUIRE THE TARGET. I PICKED UP THE TARGET; AN ACR LGT AT 3 O'CLOCK AND APPROX 1 NM; JUST AS CTR WAS ADVISING US THE TARGET WAS AN ACFT LEVELING AT FL210. AS SOON AS I PICKED UP THE TARGET; I CAME BACK INSIDE TO THE TA/VSI TO COMMENCE A DSCNT BACK TO ASSIGNED ALT. AS SOON AS THE TFC CLRED OFF TO THE R; THE 1500 FPM COMMANDED CLB WAS REMOVED FROM THE TA/VSI. WE LEVELED OFF AT FL220 AND PROCEEDED WITHOUT FURTHER INCIDENT. ATC WAS KEPT INFORMED THE ENTIRE TIME AND INFORMED US THAT THERE WAS 'NO PROB.' IMPRESSIONS: TCASII WORKED AS ADVERTISED AND THIS INCIDENT DOES NOT DIMINISH MY ENTHUSIASM FOR THIS SYS.