Narrative:

Air carrier X on vectors to ewr runway 22L ILS circle runway 29. Aircraft given a turn to 140 degrees and advised of VFR traffic 11 O'clock, 2 mi. The TAS display on 5 mi scale was checked and PIC observed altitude difference of 100'. First officer observed 400'. Simultaneously an RA 'climb' command was given with approximately 1800 FPM command. Autoplt was disconnected and climb started. 100' difference noted again and aircraft was turned further right. 'Monitor vertical' was announced at 3300' and aircraft leveled off. Light low wing civil trainer aircraft with t-tail was observed passing down left side of aircraft 300' altitude difference noted. Civil aircraft I stable flight. 'Clear of conflict' announced. This pilot feels that if TCAS had not been installed, visual acquisition only would have required a much more involved evasive maneuver. Our maneuver and the civil aircraft were noted by many passenger on the aircraft as it was. Phone conversation with ATC rep indicated mode C of trner showed 2500'. In flight visibility 3-4 mi down sun, heavy haze. Also noted single traffic annunciation and immediate RA climb. Heavy frequency congestion, but first officer managed to report altitude deviation as result of flight attendant. Both crew members agreed after visibility sighting that RA was valid and that light aircraft probably at 3000'. Supplemental information from acn 182971: we were on a right base to final 22L ILS at ewr. Altitude was 3000' MSL. The TCAS called a TA for a target that was 400' below and 11 O'clock. Approach shortly (approximately 25 seconds) called 'traffic at 11 O'clock, 2 1/2 mi, turn right to 140 degrees.' as she finished the TCAS issued an RA to climb. Since we still did not have the traffic visually, the captain followed the RA and climbed to 3400' MSL and turned to 140 degrees. As we leveled off the captain saw the aircraft pass off to the left approximately 300' below and 1/4 mi left. It appeared that the other aircraft remained straight and level the entire time. I had remarked to the captain several mins before this even that the controller seemed to be handling a lot of traffic.

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Original NASA ASRS Text

Title: ACR TAKES EVASIVE ACTION TO MISS VFR ACFT AFTER RECEIVING TRAFFIC ADVISORY AND TCASII ALERT.

Narrative: ACR X ON VECTORS TO EWR RWY 22L ILS CIRCLE RWY 29. ACFT GIVEN A TURN TO 140 DEGS AND ADVISED OF VFR TFC 11 O'CLOCK, 2 MI. THE TAS DISPLAY ON 5 MI SCALE WAS CHKED AND PIC OBSERVED ALT DIFFERENCE OF 100'. F/O OBSERVED 400'. SIMULTANEOUSLY AN RA 'CLB' COMMAND WAS GIVEN WITH APPROX 1800 FPM COMMAND. AUTOPLT WAS DISCONNECTED AND CLB STARTED. 100' DIFFERENCE NOTED AGAIN AND ACFT WAS TURNED FURTHER RIGHT. 'MONITOR VERT' WAS ANNOUNCED AT 3300' AND ACFT LEVELED OFF. LIGHT LOW WING CIVIL TRAINER ACFT WITH T-TAIL WAS OBSERVED PASSING DOWN LEFT SIDE OF ACFT 300' ALT DIFFERENCE NOTED. CIVIL ACFT I STABLE FLT. 'CLR OF CONFLICT' ANNOUNCED. THIS PLT FEELS THAT IF TCAS HAD NOT BEEN INSTALLED, VISUAL ACQUISITION ONLY WOULD HAVE REQUIRED A MUCH MORE INVOLVED EVASIVE MANEUVER. OUR MANEUVER AND THE CIVIL ACFT WERE NOTED BY MANY PAX ON THE ACFT AS IT WAS. PHONE CONVERSATION WITH ATC REP INDICATED MODE C OF TRNER SHOWED 2500'. IN FLT VISIBILITY 3-4 MI DOWN SUN, HVY HAZE. ALSO NOTED SINGLE TFC ANNUNCIATION AND IMMEDIATE RA CLB. HVY FREQ CONGESTION, BUT F/O MANAGED TO RPT ALT DEVIATION AS RESULT OF FA. BOTH CREW MEMBERS AGREED AFTER VIS SIGHTING THAT RA WAS VALID AND THAT LIGHT ACFT PROBABLY AT 3000'. SUPPLEMENTAL INFO FROM ACN 182971: WE WERE ON A RIGHT BASE TO FINAL 22L ILS AT EWR. ALT WAS 3000' MSL. THE TCAS CALLED A TA FOR A TARGET THAT WAS 400' BELOW AND 11 O'CLOCK. APCH SHORTLY (APPROX 25 SECS) CALLED 'TFC AT 11 O'CLOCK, 2 1/2 MI, TURN RIGHT TO 140 DEGS.' AS SHE FINISHED THE TCAS ISSUED AN RA TO CLB. SINCE WE STILL DID NOT HAVE THE TFC VISUALLY, THE CAPT FOLLOWED THE RA AND CLBED TO 3400' MSL AND TURNED TO 140 DEGS. AS WE LEVELED OFF THE CAPT SAW THE ACFT PASS OFF TO THE LEFT APPROX 300' BELOW AND 1/4 MI LEFT. IT APPEARED THAT THE OTHER ACFT REMAINED STRAIGHT AND LEVEL THE ENTIRE TIME. I HAD REMARKED TO THE CAPT SEVERAL MINS BEFORE THIS EVEN THAT THE CTLR SEEMED TO BE HANDLING A LOT OF TFC.

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.