Narrative:

We were on the buzzy 4 arrival, approaching the rdu airport, at 8000 ft, 250 KTS, and I was flying the aircraft. Raleigh approach control advised us traffic was at 7500 ft, 10 O'clock, and 5 mi. We saw the traffic approaching us on our TCASII display screen 500 ft below us. Both the captain and I were trying to visually identify the approaching traffic. I was hand flying the aircraft at the time. As the other aircraft came closer, the TCAS gave us a TA by announcing 'traffic, traffic'. Shortly after that, the other aircraft began climbing as he approached us. The TCASII then gave us an RA by announcing 'monitor vertical speed, monitor vertical speed'. Quickly I checked the RA/vertical speed indicator (RA/vsi), which advised us not to descend. I then glanced at the TCAS display screen and, in disbelief, observed that the other aircraft was climbing. Within seconds the TCASII announced, 'climb, climb, climb'. I checked the RA/vsi which was indicating about a 4000-5000 FPM climb. I slammed both throttles to their stops and rapidly pulled the nose up. We climbed to 8400 ft then TCASII announced, 'clear of conflict'. I idled both engines and descended back to 8000 ft while the captain advised raleigh approach of our deviation. Neither the captain nor I ever saw the other aircraft. As far as vertical separation goes, last time I looked at the TCAS display screen, the other aircraft was 300 ft below us and still climbing. I am now a firm believer of the TCASII system. I hate flying without it.

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Original NASA ASRS Text

Title: ACR MLG ALT DEV EXCURSION FROM CLRNC ALT IN RESPONSE TO TCASII RA.

Narrative: WE WERE ON THE BUZZY 4 ARR, APCHING THE RDU ARPT, AT 8000 FT, 250 KTS, AND I WAS FLYING THE ACFT. RALEIGH APCH CTL ADVISED US TFC WAS AT 7500 FT, 10 O'CLOCK, AND 5 MI. WE SAW THE TFC APCHING US ON OUR TCASII DISPLAY SCREEN 500 FT BELOW US. BOTH THE CAPT AND I WERE TRYING TO VISUALLY IDENT THE APCHING TFC. I WAS HAND FLYING THE ACFT AT THE TIME. AS THE OTHER ACFT CAME CLOSER, THE TCAS GAVE US A TA BY ANNOUNCING 'TFC, TFC'. SHORTLY AFTER THAT, THE OTHER ACFT BEGAN CLBING AS HE APCHED US. THE TCASII THEN GAVE US AN RA BY ANNOUNCING 'MONITOR VERT SPD, MONITOR VERT SPD'. QUICKLY I CHKED THE RA/VERT SPD INDICATOR (RA/VSI), WHICH ADVISED US NOT TO DSND. I THEN GLANCED AT THE TCAS DISPLAY SCREEN AND, IN DISBELIEF, OBSERVED THAT THE OTHER ACFT WAS CLBING. WITHIN SECONDS THE TCASII ANNOUNCED, 'CLB, CLB, CLB'. I CHKED THE RA/VSI WHICH WAS INDICATING ABOUT A 4000-5000 FPM CLB. I SLAMMED BOTH THROTTLES TO THEIR STOPS AND RAPIDLY PULLED THE NOSE UP. WE CLBED TO 8400 FT THEN TCASII ANNOUNCED, 'CLR OF CONFLICT'. I IDLED BOTH ENGS AND DSNDED BACK TO 8000 FT WHILE THE CAPT ADVISED RALEIGH APCH OF OUR DEV. NEITHER THE CAPT NOR I EVER SAW THE OTHER ACFT. AS FAR AS VERT SEPARATION GOES, LAST TIME I LOOKED AT THE TCAS DISPLAY SCREEN, THE OTHER ACFT WAS 300 FT BELOW US AND STILL CLBING. I AM NOW A FIRM BELIEVER OF THE TCASII SYS. I HATE FLYING WITHOUT 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.