Narrative:

Military X, H/C17/right, IFR on the airway, I never received his beacon, however, upon handoff to the los angeles area, it was determined to be my radar deficiency. These 'holes' where no secondary is received are prevalent on the west side of van nuys, but I would fully expect to have a beacon on an aircraft at 11000 ft. We routinely don't receive beacons on aircraft as high as 5500 ft, on the west side, which is unacceptable, but this deficiency appears to be getting worse. Since the installation of ASR9, our coverage is lacking, especially of secondary radar returns. Considering the fact that we work a lot of air carrier aircraft, with no class B and little class C airspace, receiving aircraft beacons is invaluable in preventing TCASII sits, or worse.

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Original NASA ASRS Text

Title: TRACON CTLR CLAIMS THAT RADAR BEACON TARGETS IN CERTAIN AREAS DO NOT APPEAR ON THE RADAR SCOPE. THE BEACON ON A MIL ACFT COULD NOT BE SEEN UNTIL HDOF.

Narrative: MIL X, H/C17/R, IFR ON THE AIRWAY, I NEVER RECEIVED HIS BEACON, HOWEVER, UPON HDOF TO THE LOS ANGELES AREA, IT WAS DETERMINED TO BE MY RADAR DEFICIENCY. THESE 'HOLES' WHERE NO SECONDARY IS RECEIVED ARE PREVALENT ON THE W SIDE OF VAN NUYS, BUT I WOULD FULLY EXPECT TO HAVE A BEACON ON AN ACFT AT 11000 FT. WE ROUTINELY DON'T RECEIVE BEACONS ON ACFT AS HIGH AS 5500 FT, ON THE W SIDE, WHICH IS UNACCEPTABLE, BUT THIS DEFICIENCY APPEARS TO BE GETTING WORSE. SINCE THE INSTALLATION OF ASR9, OUR COVERAGE IS LACKING, ESPECIALLY OF SECONDARY RADAR RETURNS. CONSIDERING THE FACT THAT WE WORK A LOT OF ACR ACFT, WITH NO CLASS B AND LITTLE CLASS C AIRSPACE, RECEIVING ACFT BEACONS IS INVALUABLE IN PREVENTING TCASII SITS, OR WORSE.

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.