Sct controller described a conflict event involving air carrier traffic inbound to ont on the ILS 26...

Narrative:

An A320 was on ILS 26L into ont just past petis NDB descending out of 3;400. I observed a VFR target without transponder from north of highway 10 southbound going to cross the ont final and issued traffic to the A320. I offered the A320 a vector around the traffic and he declined. The traffic did not merge; but only just barely. This is a known VFR transition area just below the class C at ont. The traffic was clear of the A320 and I transferred communication to ont. Subsequently I called ral tower and asked if they were talking to the aircraft without transponder; they were and I asked the altitude of the aircraft. They advised he said he was at 2;200. This is an all too common problem at ont; what I would suggest is that we protect the aircraft on the ont final better and have the east extension of ont's class C be down to the surface out to petis NDB. This problem needs to be addressed before something does happen on the final into ont.

Original NASA ASRS Text

Title: SCT Controller described a conflict event involving Air Carrier traffic inbound to ONT on the ILS 26L and VFR traffic crossing the ILS path; the reporter recommending ONT's Class C be expanded to reduce same type events.

Narrative: An A320 was on ILS 26L into ONT just past PETIS NDB descending out of 3;400. I observed a VFR target without transponder from north of Highway 10 southbound going to cross the ONT final and issued traffic to the A320. I offered the A320 a vector around the traffic and he declined. The traffic did not merge; but only just barely. This is a known VFR transition area just below the Class C at ONT. The traffic was clear of the A320 and I transferred communication to ONT. Subsequently I called RAL Tower and asked if they were talking to the aircraft without transponder; they were and I asked the altitude of the aircraft. They advised he said he was at 2;200. This is an all too common problem at ONT; what I would suggest is that we protect the aircraft on the ONT final better and have the east extension of ONT's Class C be down to the surface out to PETIS NDB. This problem needs to be addressed before something does happen on the final into ONT.

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.

Attributes
ACN	1050205
Time
Date	201211
Local Time Of Day	0001-0600
Place
Locale Reference	ONT.Airport
State Reference	CA
Aircraft 1
Make Model Name	A320
Operating Under FAR Part	Part 121
Flight Phase	Final Approach
Flight Plan	IFR
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Route In Use	None
Flight Plan	VFR
Person 1
Function	Approach Departure
Qualification	Air Traffic Control Fully Certified
Events
Anomaly	ATC Issue All Types Conflict Airborne Conflict

Sct controller described a conflict event involving air carrier traffic inbound to ont on the ILS 26L and VFR traffic crossing the ILS path; the reporter recommending ont's class C be expanded to reduce same type events.