Narrative:

I was working the east feeder radar position. This position handles lax arrs from the east of lax. I observed 4 ghost targets in about 6 mins. These were reported to my supervisor and I was told that this was entered into the facility log. We have been experiencing this for over 1 yr now. XA28 I observed a data tag with associated mode C altitude of 16000 ft about 10 mi north of civet intersection. The target appeared to be a good target and even updated a few times before coasting out. XA34 I observed 2 targets approximately 10 mi south of pdz VOR. Both targets had a mode C altitude and both had a beacon return. One was a beacon code of XXXX and displayed an altitude of 15000 ft. I later discovered that this was a ghost from air carrier X that was about 25 mi to the east. XA34 the second target was about the same location and had the same characteristics but a different code and altitude of 14000 ft. I started a local ARTS data tag on both aircraft so they could later be tracked. XA40 the last one was an lax arrival that showed on my scope about 20 mi ahead of where it actually was. Everything like an actual real airplane -- beacon; mode C; position updates; etc. The supervisor notified maintenance and he said something about resetting the buffers. This seemed to make the problem go away; but I truly believe that it will happen again. Such distrs definitely degrade safety!

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Original NASA ASRS Text

Title: SCT CTLR EXPRESSED CONCERN REGARDING GHOST TARGETS OBSERVED WHILE WORKING THE EAST FEEDER POSITION.

Narrative: I WAS WORKING THE E FEEDER RADAR POS. THIS POS HANDLES LAX ARRS FROM THE E OF LAX. I OBSERVED 4 GHOST TARGETS IN ABOUT 6 MINS. THESE WERE RPTED TO MY SUPVR AND I WAS TOLD THAT THIS WAS ENTERED INTO THE FACILITY LOG. WE HAVE BEEN EXPERIENCING THIS FOR OVER 1 YR NOW. XA28 I OBSERVED A DATA TAG WITH ASSOCIATED MODE C ALT OF 16000 FT ABOUT 10 MI N OF CIVET INTXN. THE TARGET APPEARED TO BE A GOOD TARGET AND EVEN UPDATED A FEW TIMES BEFORE COASTING OUT. XA34 I OBSERVED 2 TARGETS APPROX 10 MI S OF PDZ VOR. BOTH TARGETS HAD A MODE C ALT AND BOTH HAD A BEACON RETURN. ONE WAS A BEACON CODE OF XXXX AND DISPLAYED AN ALT OF 15000 FT. I LATER DISCOVERED THAT THIS WAS A GHOST FROM ACR X THAT WAS ABOUT 25 MI TO THE E. XA34 THE SECOND TARGET WAS ABOUT THE SAME LOCATION AND HAD THE SAME CHARACTERISTICS BUT A DIFFERENT CODE AND ALT OF 14000 FT. I STARTED A LCL ARTS DATA TAG ON BOTH ACFT SO THEY COULD LATER BE TRACKED. XA40 THE LAST ONE WAS AN LAX ARR THAT SHOWED ON MY SCOPE ABOUT 20 MI AHEAD OF WHERE IT ACTUALLY WAS. EVERYTHING LIKE AN ACTUAL REAL AIRPLANE -- BEACON; MODE C; POS UPDATES; ETC. THE SUPVR NOTIFIED MAINT AND HE SAID SOMETHING ABOUT RESETTING THE BUFFERS. THIS SEEMED TO MAKE THE PROB GO AWAY; BUT I TRULY BELIEVE THAT IT WILL HAPPEN AGAIN. SUCH DISTRS DEFINITELY DEGRADE SAFETY!

Data retrieved from NASA's ASRS site as of January 2009 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.