A C172 PLT RPTS HAVING AN NMAC WITH A C152 AS THE RPTR WAS COMPLYING WITH THE LCL NOISE ABATEMENT PROC.

Narrative

I WAS DEPARTING L32 FROM RWY 24. I WAS IN THE PRESCRIBED NOISE ABATEMENT PATTERN. I WAS FLYING A C172N (180 HP). AS I TURNED R TO HEAD BACK OVER THE ARPT; I ANNOUNCED MY DIRECTION OVER FREQ 123.0. I HAD COMPLETED MY TURN AND IMMEDIATELY I OBSERVED A C152 PASSING SBOUND DIRECTLY IN FRONT AND ABOVE ME. HE WAS JUST PASSING MY LINE OF FLT. I CALLED OUT TO THE C152 ON FREQ 123.0; BUT RECEIVED NO RESPONSE. I WATCHED THE C152 CONTINUE SBOUND AND DSNDING ALONG THE COAST LINE. I LOST SIGHT OF HIM AS HE NEARED THE SDG&E PWR PLANT. I CALLED THE CRQ TWR AND INQUIRED IF THEY HAD TFC COMING IN FROM THE COAST FROM THE AREA OF THE PWR PLANT. THIS WAS PROBABLY 3 OR 4 MINS AFTER I LOST SIGHT OF THE C152. THE TWR RPTED TFC; BUT NOT A C152 (I DON'T KNOW WHY THEY DENIED KNOWING OF THE C152). I THEN CONTACTED SOCAL APCH ON 127.3 AND ASKED THEM IF THEY HAD TRACKED TFC THAT HAD COME DOWN THE COAST. HE INFORMED ME THAT HE HAD NOT. I CONTINUED TO MONITOR SOCAL APCH AND ALMOST IMMEDIATELY HEARD A CESSNA REQUESTING FLT FOLLOWING TO EL MONTE. I BELIEVE HE HAD JUST DEPARTED CRQ. AFTER OBTAINING APPROVAL FROM SOCAL; I CONTACTED OTHER PLT DIRECTLY. HE ADMITTED THAT HE WAS THE TFC I HAD BEEN 'LOOKING FOR.' HE THEN RELATED THAT HE SAW ME PASS UNDER HIM; THAT HE WAS IN RADAR CONTACT WITH THE CRQ TWR; BUT THEY DID NOT ALERT HIM OF MY PRESENCE.