Narrative:

TCASII sounded a TA at 11 O'clock relative altitude plus 200 ft. Seconds later, as visual contact was made, a climb RA sounded. Climb was initiated and small aircraft traffic passed within 1 mi and underneath to the right. We returned to 2500 ft from 2900 ft after 'clear of conflict' was announced. Did not know the traffic was in radio and radar contact with approach control, had us in sight and had accepted visual separation responsibilities. The separation was inadequate in my opinion, however, and ATC even questioned the small aircraft pilot about it. We informed ATC of the maneuver in response to a TCASII RA. TCASII had worked well and I was thankful to have it on board.

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Original NASA ASRS Text

Title: ALTDEV ALT EXCURSION IN PLT RESPONSE TO TCASII RA WHEN IT SENSED A POTENTIAL CONFLICT.

Narrative: TCASII SOUNDED A TA AT 11 O'CLOCK RELATIVE ALT PLUS 200 FT. SECONDS LATER, AS VISUAL CONTACT WAS MADE, A CLB RA SOUNDED. CLB WAS INITIATED AND SMA TFC PASSED WITHIN 1 MI AND UNDERNEATH TO THE R. WE RETURNED TO 2500 FT FROM 2900 FT AFTER 'CLR OF CONFLICT' WAS ANNOUNCED. DID NOT KNOW THE TFC WAS IN RADIO AND RADAR CONTACT WITH APCH CTL, HAD US IN SIGHT AND HAD ACCEPTED VISUAL SEPARATION RESPONSIBILITIES. THE SEPARATION WAS INADEQUATE IN MY OPINION, HOWEVER, AND ATC EVEN QUESTIONED THE SMA PLT ABOUT IT. WE INFORMED ATC OF THE MANEUVER IN RESPONSE TO A TCASII RA. TCASII HAD WORKED WELL AND I WAS THANKFUL TO HAVE IT ON BOARD.

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.