Narrative:

While flying into van nuys airport today in rather poor and overcast WX, I was following the FAA published instrument landing procedure (ILS for runway 16R) and about 4 mi north of the airport, when I suddenly found myself face to face with a northbound airplane, small aircraft Y, at extremely short range, and getting closer. We were at the same altitude, but on reciprocal courses. Since I had just broken out of the base of the clouds, it was quite a surprise. Fortunately, I was able to maneuver my aircraft to the side and missed the oncoming aircraft by about a hundred feet or so. A larger and faster plane might not have been so lucky. I immediately reported this incident to the van nuys tower, and when on the ground talked to them on the telephone about it. Their reaction was less than satisfying. The van nuys tower denied ever seeing the other plane on their radar, and said the burbank ATC reported no planes in that vicinity. Furthermore, they said that this type of thing happens quite frequently because they can't keep track of the planes in the air. It is rumored, and unofficially acknowledged by some air traffic controllers, that ATC turns off the VFR transponder returns on their radar because it just clutters up the screens. The system just can't handle that many airplanes.

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Original NASA ASRS Text

Title: NMAC BETWEEN SMA X ON ILS TO RWY 16 AT VNY, AND SMA Y WHICH IS NOT IN CONTACT WITH ATC.

Narrative: WHILE FLYING INTO VAN NUYS ARPT TODAY IN RATHER POOR AND OVCST WX, I WAS FOLLOWING THE FAA PUBLISHED INSTRUMENT LNDG PROC (ILS FOR RWY 16R) AND ABOUT 4 MI N OF THE ARPT, WHEN I SUDDENLY FOUND MYSELF FACE TO FACE WITH A NBOUND AIRPLANE, SMA Y, AT EXTREMELY SHORT RANGE, AND GETTING CLOSER. WE WERE AT THE SAME ALT, BUT ON RECIPROCAL COURSES. SINCE I HAD JUST BROKEN OUT OF THE BASE OF THE CLOUDS, IT WAS QUITE A SURPRISE. FORTUNATELY, I WAS ABLE TO MANEUVER MY ACFT TO THE SIDE AND MISSED THE ONCOMING ACFT BY ABOUT A HUNDRED FEET OR SO. A LARGER AND FASTER PLANE MIGHT NOT HAVE BEEN SO LUCKY. I IMMEDIATELY RPTED THIS INCIDENT TO THE VAN NUYS TWR, AND WHEN ON THE GND TALKED TO THEM ON THE TELEPHONE ABOUT IT. THEIR REACTION WAS LESS THAN SATISFYING. THE VAN NUYS TWR DENIED EVER SEEING THE OTHER PLANE ON THEIR RADAR, AND SAID THE BURBANK ATC RPTED NO PLANES IN THAT VICINITY. FURTHERMORE, THEY SAID THAT THIS TYPE OF THING HAPPENS QUITE FREQUENTLY BECAUSE THEY CAN'T KEEP TRACK OF THE PLANES IN THE AIR. IT IS RUMORED, AND UNOFFICIALLY ACKNOWLEDGED BY SOME AIR TFC CTLRS, THAT ATC TURNS OFF THE VFR TRANSPONDER RETURNS ON THEIR RADAR BECAUSE IT JUST CLUTTERS UP THE SCREENS. THE SYS JUST CAN'T HANDLE THAT MANY AIRPLANES.

Data retrieved from NASA's ASRS site as of July 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.