Narrative:

We were handed off to bur approach about 30 NM out and 10000'. As I remember ATIS was saying X6F. At our position it was more like 2 NM visibility. Everything proceeded normally until about 4800' MSL when I noticed an small aircraft at about 11:30-12 O'clock and same altitude, and approximately 1 mi. As we were descending at 1000' FPM it was apparent to me that there would not be a problem as we would pass slightly under (300') and to the west of the traffic. I questioned approach on this and they said they did not see anything on their radar. About 15-30 seconds later approach called with 'traffic at 1 O'clock and 1-2 mi, probably out of the pattern at vny.' as the first officer was flying I immediately searched for the traffic and a few moments later an small aircraft (blue and white, I think) passed directly under us at about 2800' MSL. No evasive action was taken because by that time it was too late. We finished the approach, made a normal landing. After we blocked in I called tower to get the number of approach control, but after talking to them (tower) and understanding the situation at vny I felt it was not necessary. Also, I should mention that although ATIS was saying visibility was 6F, the visibility was probably only 1 1/2-2 NM at the field as we picked up the runway at about that distance. As I understand it, aircraft operating from another field in a control zone do not have to be in contact with ATC at the primary airport. In this case and probably others, the potential for disaster looms very large. I believe some changes should be made to at least keep traffic from the approach path where higher speed aircraft are operating and where approachs are known to be in progress.

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Original NASA ASRS Text

Title: ACR MLG, ON ILS APCH TO BUR, CAME VERY CLOSE TO SMA WHILE OVER VNY ARPT.

Narrative: WE WERE HANDED OFF TO BUR APCH ABOUT 30 NM OUT AND 10000'. AS I REMEMBER ATIS WAS SAYING X6F. AT OUR POS IT WAS MORE LIKE 2 NM VISIBILITY. EVERYTHING PROCEEDED NORMALLY UNTIL ABOUT 4800' MSL WHEN I NOTICED AN SMA AT ABOUT 11:30-12 O'CLOCK AND SAME ALT, AND APPROX 1 MI. AS WE WERE DSNDING AT 1000' FPM IT WAS APPARENT TO ME THAT THERE WOULD NOT BE A PROB AS WE WOULD PASS SLIGHTLY UNDER (300') AND TO THE W OF THE TFC. I QUESTIONED APCH ON THIS AND THEY SAID THEY DID NOT SEE ANYTHING ON THEIR RADAR. ABOUT 15-30 SECS LATER APCH CALLED WITH 'TFC AT 1 O'CLOCK AND 1-2 MI, PROBABLY OUT OF THE PATTERN AT VNY.' AS THE F/O WAS FLYING I IMMEDIATELY SEARCHED FOR THE TFC AND A FEW MOMENTS LATER AN SMA (BLUE AND WHITE, I THINK) PASSED DIRECTLY UNDER US AT ABOUT 2800' MSL. NO EVASIVE ACTION WAS TAKEN BECAUSE BY THAT TIME IT WAS TOO LATE. WE FINISHED THE APCH, MADE A NORMAL LNDG. AFTER WE BLOCKED IN I CALLED TWR TO GET THE NUMBER OF APCH CONTROL, BUT AFTER TALKING TO THEM (TWR) AND UNDERSTANDING THE SITUATION AT VNY I FELT IT WAS NOT NECESSARY. ALSO, I SHOULD MENTION THAT ALTHOUGH ATIS WAS SAYING VISIBILITY WAS 6F, THE VISIBILITY WAS PROBABLY ONLY 1 1/2-2 NM AT THE FIELD AS WE PICKED UP THE RWY AT ABOUT THAT DISTANCE. AS I UNDERSTAND IT, ACFT OPERATING FROM ANOTHER FIELD IN A CTL ZONE DO NOT HAVE TO BE IN CONTACT WITH ATC AT THE PRIMARY ARPT. IN THIS CASE AND PROBABLY OTHERS, THE POTENTIAL FOR DISASTER LOOMS VERY LARGE. I BELIEVE SOME CHANGES SHOULD BE MADE TO AT LEAST KEEP TFC FROM THE APCH PATH WHERE HIGHER SPD ACFT ARE OPERATING AND WHERE APCHS ARE KNOWN TO BE IN PROGRESS.

Data retrieved from NASA's ASRS site as of August 2007 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.