Narrative:

We were vectored for downwind runway 16R at den. On base turn; metroliner traffic was pointed out for runway 16L and we called that traffic and runway 16R in sight. We were then cleared for the visual runway 16R with 'maintain visual separation from the parallel traffic; turn 140 degrees to intercept; maintain 170 to jetsn; contact tower at jetsn 135.3.' the first officer turned to 140 degrees and configured flaps 2 degrees and we agreed to remain right of course to allow for some track error by the metroliner. The winds were from 080 degrees at that point (an overshoot for them). The metroliner was directly abeam us as we approached 4 miles from jetsn. It was at this point tht I attempted to take the TCAS out of the 'traffic' position to the 'TA' to avoid what I considered to be a certain RA in this situation. (Please understand that I just got out of school on this thing in december and there was no training in regard to differences between the behavior of TCAS in our airbus fleet and the boeing fleet.) I flipped the switch from 'traffic' to 'TA/RA' without looking at the switch as I was looking at the traffic; which looked very close to us -- so close that I suspected he'd lined up to the wrong runway (we were still more than 1 dot right to stay away from him). When I flipped that switch out of 'traffic;' the TCAS display went blank -- an unexpected outcome. We were now 3 miles from jetsn and I switched tower where the frequency was busy. I asked the first officer (who was very experienced with the airbus) if the TCAS blanking in 'TA' was normal (we were both very busy at this point). He said; 'no I don't think it should do that.' so; I put the switch back to 'traffic' as I wanted the system to be available even knowing that an RA was likely at this point. The tower frequency was still clobbered by an aircraft checking in visual to runway 16R. Since I knew approach was directing tower check-in at jetsn; and we were nearly at jetsn; and we were also for runway 16R; I asked the first officer for further right of course; which he did. TCAS then went RA with 'climb; climb' red to 1;500 ft up. I said; 'comply' as most of the evidence was pointing to a direct conflict with the aircraft to our left. The first officer took a second to understand that I was directing compliance to the RA and not the approach guidance; but he did comply within required time. The RA discontinued immediately with our climb and we were now just crossing jetsn at 6;800 ft and I told tower we were discontinuing the approach due to an RA. Tower had us stay on runway 16R localizer and level at 8;000 ft. This was not a go around nor was it a 'soft-go.' rather; we simply complied with the RA using pitch and power then smoothly leveled at 8;000 ft. The box did 'eat' the runway; but I had plenty of time to reload it; re-run the approach/descent checklist and make an announcement to the people and re-prepare for landing. The aircraft was being hand flown with autopilot/autothrust off and flight directors on. The gear was not down as we were outside the fix. We remained on speed 170 KTS at flaps 2 degrees. The first officer was very smooth and deliberate in his flying. I don't know what the actual spacing was with the aircraft to our left. It was night and the navigation light was all I could see of the metroliner. It is possible that our discontinuation of the approach may have been unnecessary; but I had enough indication that something was wrong and that discontinuation was the safest course of action. Tower's reaction was simply to assign 8000 ft and directed us to remain on the localizer. At the gate; we felt it was possible that the aircraft behind us checked in early causing me to conclude that our parallel traffic was to runway 16R when he was actually on runway 16L.

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Original NASA ASRS Text

Title: New A320 Captain's unfamiliarity with the fleet's TCAS system contributes to the need to respond to a TCAS RA on approach to parallel runways.

Narrative: We were vectored for downwind Runway 16R at DEN. On base turn; Metroliner traffic was pointed out for Runway 16L and we called that traffic and Runway 16R in sight. We were then cleared for the visual Runway 16R with 'maintain visual separation from the parallel traffic; turn 140 degrees to intercept; maintain 170 to JETSN; contact Tower at JETSN 135.3.' The First Officer turned to 140 degrees and configured flaps 2 degrees and we agreed to remain right of course to allow for some track error by the Metroliner. The winds were from 080 degrees at that point (an overshoot for them). The Metroliner was directly abeam us as we approached 4 miles from JETSN. It was at this point tht I attempted to take the TCAS out of the 'traffic' position to the 'TA' to avoid what I considered to be a certain RA in this situation. (Please understand that I just got out of school on this thing in December and there was NO training in regard to differences between the behavior of TCAS in our Airbus fleet and the Boeing fleet.) I flipped the switch from 'traffic' to 'TA/RA' without looking at the switch as I was looking at the traffic; which looked VERY close to us -- so close that I suspected he'd lined up to the wrong runway (we were still more than 1 dot right to stay away from him). When I flipped that switch out of 'traffic;' the TCAS display went blank -- an unexpected outcome. We were now 3 miles from JETSN and I switched Tower where the frequency was busy. I asked the First Officer (who was very experienced with the Airbus) if the TCAS blanking in 'TA' was normal (we were both very busy at this point). He said; 'No I don't think it should do that.' So; I put the switch back to 'traffic' as I wanted the system to be available even knowing that an RA was likely at this point. The Tower frequency was still clobbered by an aircraft checking in visual to Runway 16R. Since I knew Approach was directing Tower check-in at JETSN; and we were nearly at JETSN; and we were also for Runway 16R; I asked the First Officer for further right of course; which he did. TCAS then went RA with 'climb; climb' red to 1;500 FT up. I said; 'comply' as most of the evidence was pointing to a direct conflict with the aircraft to our left. The First Officer took a second to understand that I was directing compliance to the RA and not the Approach guidance; but he did comply within required time. The RA discontinued immediately with our climb and we were now just crossing JETSN at 6;800 FT and I told Tower we were discontinuing the approach due to an RA. Tower had us stay on Runway 16R LOC and level at 8;000 FT. This was not a go around nor was it a 'Soft-Go.' Rather; we simply complied with the RA using pitch and power then smoothly leveled at 8;000 FT. The box did 'eat' the runway; but I had plenty of time to reload it; re-run the Approach/Descent checklist and make an announcement to the people and re-prepare for landing. The aircraft was being hand flown with autopilot/autothrust off and flight directors on. The gear was not down as we were outside the fix. We remained on speed 170 KTS at flaps 2 degrees. The First Officer was very smooth and deliberate in his flying. I don't know what the actual spacing was with the aircraft to our left. It was night and the Navigation light was all I could see of the Metroliner. It is possible that our discontinuation of the approach may have been unnecessary; but I had enough indication that something was wrong and that discontinuation was the safest course of action. Tower's reaction was simply to assign 8000 FT and directed us to remain on the LOC. At the gate; we felt it was possible that the aircraft behind us checked in early causing me to conclude that our parallel traffic was to Runway 16R when he was actually on Runway 16L.

Data retrieved from NASA's ASRS site as of April 2012 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.