Narrative:

Weather dictated that IFR arrival aircraft be vectored at least 2 miles outside the approach gate. The safest MVA at that point for aircraft on a right base to final is 3;700 ft. This altitude was blocked by a VFR aircraft eastbound at 3;500 ft; so I descended air carrier X to 3;000 ft. This is a safe altitude as long as the arrival intercepts the final. After issuing traffic to both air carrier X and the VFR aircraft; I turned air carrier X to heading 180 degrees to intercept the final approach course. His turn took him through the localizer; so I corrected his heading and issued him an immediate right turn to 220 to intercept. When I questioned the pilot's turn rate he replied; 'standard; but we were a little slow on our turn' or something like that. I guess it would have been better for air carrier X to intercept above glide slope (4;000 ft) in order to stay above the VFR aircraft in this case. It would have been tedious to try to move the VFR out of the way of air carrier X as there were additional aircraft inbound as well. Since the MVA's in this area were raised; this 'spill-out' occurs fairly frequently. We are diligent in trying to prevent it from occurring; but occasionally it still does.

Google
 

Original NASA ASRS Text

Title: SCT Controller described a below MVA event when an Air Carrier aircraft was being separated from VFR traffic; turned to intercept localizer; but failed to capture ending up in a lower MVA area.

Narrative: Weather dictated that IFR arrival aircraft be vectored at least 2 miles outside the approach gate. The safest MVA at that point for aircraft on a right base to final is 3;700 FT. This altitude was blocked by a VFR aircraft eastbound at 3;500 FT; so I descended Air Carrier X to 3;000 FT. This is a safe altitude as long as the arrival intercepts the final. After issuing traffic to both Air Carrier X and the VFR aircraft; I turned Air Carrier X to heading 180 degrees to intercept the final approach course. His turn took him through the localizer; so I corrected his heading and issued him an immediate right turn to 220 to intercept. When I questioned the pilot's turn rate he replied; 'Standard; but we were a little slow on our turn' or something like that. I guess it would have been better for Air Carrier X to intercept above glide slope (4;000 FT) in order to stay above the VFR aircraft in this case. It would have been tedious to try to move the VFR out of the way of Air Carrier X as there were additional aircraft inbound as well. Since the MVA's in this area were raised; this 'spill-out' occurs fairly frequently. We are diligent in trying to prevent it from occurring; but occasionally it still does.

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.