Narrative:

While on descent; we received a TCAS TA for traffic that was about 5 miles ahead of us; approximately 1;000' below us; as we were in a descent from 5;000' to 4;000'. I was performing an idle descent in speed mode at 250 KIAS. I immediately selected vs mode and reduced the descent rate to -1;000 FPM to attempt to avoid a TCAS RA. Within two or three seconds; pittsburgh approach advised us of an aircraft; 11 o'clock; maneuvering at 3;500'; 3 NM; VFR. We immediately spotted him; eastbound; at the prescribed altitude. I advised my first officer that this is just setting us up for a TCAS RA as he was going to cross directly below us; and told him to prepare for it as I shallowed the descent to 300 FPM.nearly instantly; we received a TCAS RA to 'monitor vertical speed'. I disengaged the autopilot to reduce our descent rate to zero while instructing my first officer to advise pittsburgh approach that we were complying with an RA. While doing that; we received a second TCAS RA to 'adjust vertical speed' of approximately 100-300 FPM climb. I climbed to 4;100 while slowing down and we received a 'clear of conflict' notice. I returned back to 4;000' and then TRACON cleared us for the visual approach to runway 28C.ATC cannot allow a passenger jet to overfly a small; single-engine aircraft with only 500' of separation. Sadly; every RA I've ever had (three) have been because of this exact situation; so I've become accustomed to how to deal with them.

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Original NASA ASRS Text

Title: CRJ-200 Captain reported responding to an RA while on final approach to 28C at PIT due to opposite direction VFR traffic also under ATC control.

Narrative: While on descent; we received a TCAS TA for traffic that was about 5 miles ahead of us; approximately 1;000' below us; as we were in a descent from 5;000' to 4;000'. I was performing an idle descent in SPD Mode at 250 KIAS. I immediately selected VS Mode and reduced the descent rate to -1;000 FPM to attempt to avoid a TCAS RA. Within two or three seconds; Pittsburgh Approach advised us of an aircraft; 11 o'clock; maneuvering at 3;500'; 3 NM; VFR. We immediately spotted him; Eastbound; at the prescribed altitude. I advised my First Officer that this is just setting us up for a TCAS RA as he was going to cross directly below us; and told him to prepare for it as I shallowed the descent to 300 FPM.Nearly instantly; we received a TCAS RA to 'Monitor Vertical Speed'. I disengaged the autopilot to reduce our descent rate to zero while instructing my First Officer to advise Pittsburgh Approach that we were complying with an RA. While doing that; we received a second TCAS RA to 'Adjust Vertical Speed' of approximately 100-300 FPM climb. I climbed to 4;100 while slowing down and we received a 'Clear of Conflict' notice. I returned back to 4;000' and then TRACON cleared us for the visual approach to Runway 28C.ATC cannot allow a passenger jet to overfly a small; single-engine aircraft with only 500' of separation. Sadly; every RA I've ever had (three) have been because of this exact situation; so I've become accustomed to how to deal with them.

Data retrieved from NASA's ASRS site 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.