A320
Flight Crew Last 90 Days 170; Flight Crew Total 9500; Flight Crew Type 6600
Training / Qualification; Distraction
Conflict NMAC
Flight Crew Returned To Clearance; Flight Crew Took Evasive Action; Flight Crew FLC complied w / Automation / Advisory
Procedure; Airport; Environment - Non Weather Related
We were cleared for a visual approach to Runway 26R at Ontario; CA. We were configured and descending on the glide slope. At about 5 miles from the runway Tower called traffic at 11 o'clock. They stated they were not in contact with them and intentions were unknown. We began looking to see the traffic and saw it on TCAS. It was about 3 miles away. The terrain and buildings on the ground made it impossible for us to visually acquire the traffic. Then the TCAS target went to a TA. We were still trying to find the traffic and then the TCAS RA occurred. I started a shallow climb to comply with the vertical guidance. The traffic passed 450 FT below us; and we were never able to see the other aircraft. After clear of conflict received; we reported the TCAS climb to the Tower. Then I started to descend again and recaptured the glide path. Then we made a normal landing.
[Report contains no additional information.]
An A320 crew on approach to ONT Runway 26R took evasive action to a TCAS RA as an aircraft passed about 450 FT beneath their aircraft.