Narrative:

I was approaching lvk from the north and was instructed by the tower to report 2 mi right base for runway 25R. When I reached that point; I reported my position and while on the radio with lvk tower I had to take evasive action to avoid a northbound cessna at the same altitude; 1400 ft MSL. The cessna had been reported to me at my initial call to be maneuvering over the 'jump zone.' this is an inexact area within the lvk class D airspace approximately 3 mi to the east of the conflict site. I have been based at lvk for some 25 yrs and I know approximately where the 'jump zone' was. When it was in use there was a dirt strip there. It has not been used for many yrs and I cannot pinpoint it from the air now. I had 2 conversations with tower personnel who tell me they don't have anything on paper to identify the location of the 'jump zone' definitively. I questioned whether it was safe for aircraft to practice ground reference maneuvers inside the class D airspace and was advised by the acting tower chief that this was common at lvk and hwd and there was nothing the FAA tower could do about it.

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Original NASA ASRS Text

Title: MOONEY 20C PLT HAS A CLOSE ENCOUNTER WITH ANOTHER ACFT DURING ENTRY INTO THE TFC PATTERN AT LVK.

Narrative: I WAS APCHING LVK FROM THE N AND WAS INSTRUCTED BY THE TWR TO RPT 2 MI R BASE FOR RWY 25R. WHEN I REACHED THAT POINT; I RPTED MY POS AND WHILE ON THE RADIO WITH LVK TWR I HAD TO TAKE EVASIVE ACTION TO AVOID A NBOUND CESSNA AT THE SAME ALT; 1400 FT MSL. THE CESSNA HAD BEEN RPTED TO ME AT MY INITIAL CALL TO BE MANEUVERING OVER THE 'JUMP ZONE.' THIS IS AN INEXACT AREA WITHIN THE LVK CLASS D AIRSPACE APPROX 3 MI TO THE E OF THE CONFLICT SITE. I HAVE BEEN BASED AT LVK FOR SOME 25 YRS AND I KNOW APPROX WHERE THE 'JUMP ZONE' WAS. WHEN IT WAS IN USE THERE WAS A DIRT STRIP THERE. IT HAS NOT BEEN USED FOR MANY YRS AND I CANNOT PINPOINT IT FROM THE AIR NOW. I HAD 2 CONVERSATIONS WITH TWR PERSONNEL WHO TELL ME THEY DON'T HAVE ANYTHING ON PAPER TO IDENT THE LOCATION OF THE 'JUMP ZONE' DEFINITIVELY. I QUESTIONED WHETHER IT WAS SAFE FOR ACFT TO PRACTICE GND REF MANEUVERS INSIDE THE CLASS D AIRSPACE AND WAS ADVISED BY THE ACTING TWR CHIEF THAT THIS WAS COMMON AT LVK AND HWD AND THERE WAS NOTHING THE FAA TWR COULD DO ABOUT IT.

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.