Narrative:

The north final controller and I were working the finals. It was a slow period of traffic volume. The supervisor at the time was having a conversation with both of us while we were on position. The north final's conflict alert (ca) started to go off which caught our attention. His aircraft responded to an RA; but didn't see the other aircraft who was VFR not talking to any controller. It was a class B violator at 9;500 ft MSL. Once I heard the ca go off on his aircraft; I told my aircraft who was staggered behind and to the left on the south final to expedite his decent thinking he could get below the target. He then replied he was responding to an RA. He did see the aircraft. He then filed a near mid air when he landed. The east feeder sector also never saw the target. The [previous] controller was controlling both the north and south final aircraft. I would recommend a better alert/awareness during periods of slow traffic. Meaning both management and the controllers involved; which I believe were all three controllers and the supervisor. The feeder controller missed the class B violator; the north final controller; me; and the supervisor who was standing around us

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Original NASA ASRS Text

Title: TRACON Controller described a TCAS RA event when IFR traffic inbound to the airport responded to unknown VFR traffic identified as a Class B violator.

Narrative: The North Final Controller and I were working the finals. It was a slow period of traffic volume. The supervisor at the time was having a conversation with both of us while we were on position. The North Final's Conflict Alert (CA) started to go off which caught our attention. His aircraft responded to an RA; but didn't see the other aircraft who was VFR not talking to any Controller. It was a Class B violator at 9;500 FT MSL. Once I heard the CA go off on his aircraft; I told my aircraft who was staggered behind and to the left on the South Final to expedite his decent thinking he could get below the target. He then replied he was responding to an RA. He did see the aircraft. He then filed a near mid air when he landed. The East Feeder sector also never saw the target. The [previous] Controller was controlling both the north and south final aircraft. I would recommend a better alert/awareness during periods of slow traffic. Meaning both management and the controllers involved; which I believe were all three controllers and the supervisor. The Feeder Controller missed the Class B violator; the North Final Controller; me; and the supervisor who was standing around us

Data retrieved from NASA's ASRS site as of July 2013 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.