Narrative:

In level cruise at FL220, received a TCASII TA on a contact at approximately 4 mi at 12:30 position. About 3 seconds later, as traffic continued to close, an RA was issued as target was at approximately 3 NM, 1 O'clock position, approximately 1400 ft below and climbing. RA commanded a 1500 FPM climb. I promptly disconnected the autoplt and commenced 1500 FPM climb while asking the captain to advise center that we were climbing in response to an RA. With the 1500 FPM climb established I scanned outside to acquire the target. I picked up the target, an air carrier large transport at 3 O'clock and approximately 1 NM, just as center was advising us the target was an aircraft leveling at FL210. As soon as I picked up the target, I came back inside to the TA/vsi to commence a descent back to assigned altitude. As soon as the traffic cleared off to the right, the 1500 FPM commanded climb 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 problem.' impressions: TCASII worked as advertised and this incident does not diminish my enthusiasm for this system.

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Original NASA ASRS Text

Title: 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.

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.