Narrative:

My aircraft was between 12500 ft and 12700 ft in good VFR between cumulus build-ups, and above the undercast by 1000 ft variable. I was climbing to 14500 ft to remain VFR and in constant communication with the controller -- having informed him that I was deviating on my altitude and heading -- average heading 290 degrees to ave (avenal). Within the event time frame I was informed of 2 targets -- one a commercial airliner which was in sight, crossing from east to west, 2-3 mi in front. The second target, a cessna 210 reported at 1:30 O'clock position, 13000 ft and not in sight. This target must have been in or behind cloud and pointed at me. The next report by the controller (who was in communication with both aircraft), was that the cessna was at my altitude 12700 ft about 11-12 O'clock position. This aircraft passed behind at about 400 ft and 50 ft high. The C210 was clearly obscured by cloud and closing on me. If he was under IFR plan he should have been held at 13000 ft or vectored away or I should have been vectored or allowed to continue climbing to avoid potential 'conflict.' the controller was in good communication with both aircraft but also concerned with other commercial traffic entering the la area via the lhs and gmn avenues. There seemed to have been plenty of time from the 'initial' indication of a conflict for the controller to deviate either aircraft to avoid this incident. He knew neither pilot could see the other aircraft. In the same 5 or 6 mins I had described to him my good visual conditions -- having easily seen the commercial jet that was pointed out. I had no constraints by clouds to stop me from being vectored away, under VFR conditions.

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Original NASA ASRS Text

Title: SINGLE PLT HAS AN NMAC WITH ANOTHER ACFT WHILE UNDER FLT FOLLOWING.

Narrative: MY ACFT WAS BTWN 12500 FT AND 12700 FT IN GOOD VFR BTWN CUMULUS BUILD-UPS, AND ABOVE THE UNDERCAST BY 1000 FT VARIABLE. I WAS CLBING TO 14500 FT TO REMAIN VFR AND IN CONSTANT COM WITH THE CTLR -- HAVING INFORMED HIM THAT I WAS DEVIATING ON MY ALT AND HDG -- AVERAGE HDG 290 DEGS TO AVE (AVENAL). WITHIN THE EVENT TIME FRAME I WAS INFORMED OF 2 TARGETS -- ONE A COMMERCIAL AIRLINER WHICH WAS IN SIGHT, XING FROM E TO W, 2-3 MI IN FRONT. THE SECOND TARGET, A CESSNA 210 RPTED AT 1:30 O'CLOCK POS, 13000 FT AND NOT IN SIGHT. THIS TARGET MUST HAVE BEEN IN OR BEHIND CLOUD AND POINTED AT ME. THE NEXT RPT BY THE CTLR (WHO WAS IN COM WITH BOTH ACFT), WAS THAT THE CESSNA WAS AT MY ALT 12700 FT ABOUT 11-12 O'CLOCK POS. THIS ACFT PASSED BEHIND AT ABOUT 400 FT AND 50 FT HIGH. THE C210 WAS CLRLY OBSCURED BY CLOUD AND CLOSING ON ME. IF HE WAS UNDER IFR PLAN HE SHOULD HAVE BEEN HELD AT 13000 FT OR VECTORED AWAY OR I SHOULD HAVE BEEN VECTORED OR ALLOWED TO CONTINUE CLBING TO AVOID POTENTIAL 'CONFLICT.' THE CTLR WAS IN GOOD COM WITH BOTH ACFT BUT ALSO CONCERNED WITH OTHER COMMERCIAL TFC ENTERING THE LA AREA VIA THE LHS AND GMN AVENUES. THERE SEEMED TO HAVE BEEN PLENTY OF TIME FROM THE 'INITIAL' INDICATION OF A CONFLICT FOR THE CTLR TO DEVIATE EITHER ACFT TO AVOID THIS INCIDENT. HE KNEW NEITHER PLT COULD SEE THE OTHER ACFT. IN THE SAME 5 OR 6 MINS I HAD DESCRIBED TO HIM MY GOOD VISUAL CONDITIONS -- HAVING EASILY SEEN THE COMMERCIAL JET THAT WAS POINTED OUT. I HAD NO CONSTRAINTS BY CLOUDS TO STOP ME FROM BEING VECTORED AWAY, UNDER VFR CONDITIONS.

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.