Narrative:

I was PNF on first leg of trip going atl-ewr. On rbv 1 arrival to ewr, last clearance from ATC was to 10000 ft. Passing 11000 ft, I noted traffic ahead on the TCASII showing level 10000 ft, 6 mi. I tracked the traffic and it continued to close, now co-altitude. Before I could query ATC, an RA was received from TCASII, 'descend, descend.' first officer respected alert and I reported to ATC we were descending. He called the traffic 1 1/2 mi ahead and I picked it up visually as it passed on the left, opposite direction. Maximum altitude deviation before recovering to 10000 ft was 300-400 ft. Closest distance was 1 - 1 1/2 mi horizontal and 200-300 ft vertical. ATC then switched us to approach control. I assume ATC neglected to issue clearance to 8000 ft over rbv, normal for the arrival, resulting in the traffic conflict. TCASII was a definite aid, first in permitting situational awareness to observe the developing problem, then issuing evasive instructions to avoid it.

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Original NASA ASRS Text

Title: ACR B727 FLC INITIATES EVASIVE MANEUVER DUE TO TCASII ALERT FOR OPPOSITE DIRECTION TFC AT THE SAME ALT. CTLR BECOMES AWARE OF SIT AND ISSUES CTL INSTRUCTIONS, BUT IN INSUFFICIENT TIME. FLC HAD ALREADY INITIATED THEIR REACTION TO TCASII.

Narrative: I WAS PNF ON FIRST LEG OF TRIP GOING ATL-EWR. ON RBV 1 ARR TO EWR, LAST CLRNC FROM ATC WAS TO 10000 FT. PASSING 11000 FT, I NOTED TFC AHEAD ON THE TCASII SHOWING LEVEL 10000 FT, 6 MI. I TRACKED THE TFC AND IT CONTINUED TO CLOSE, NOW CO-ALT. BEFORE I COULD QUERY ATC, AN RA WAS RECEIVED FROM TCASII, 'DSND, DSND.' FO RESPECTED ALERT AND I RPTED TO ATC WE WERE DSNDING. HE CALLED THE TFC 1 1/2 MI AHEAD AND I PICKED IT UP VISUALLY AS IT PASSED ON THE L, OPPOSITE DIRECTION. MAX ALTDEV BEFORE RECOVERING TO 10000 FT WAS 300-400 FT. CLOSEST DISTANCE WAS 1 - 1 1/2 MI HORIZ AND 200-300 FT VERT. ATC THEN SWITCHED US TO APCH CTL. I ASSUME ATC NEGLECTED TO ISSUE CLRNC TO 8000 FT OVER RBV, NORMAL FOR THE ARR, RESULTING IN THE TFC CONFLICT. TCASII WAS A DEFINITE AID, FIRST IN PERMITTING SITUATIONAL AWARENESS TO OBSERVE THE DEVELOPING PROB, THEN ISSUING EVASIVE INSTRUCTIONS TO AVOID IT.

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.