Narrative:

We were on the pomona 1 departure from ont. WX was broken cumulus clouds from 4000'-10000' MSL, with good visibility between clouds. Upon our handoff from ont departure control, as we were leveling off at 7000' over pom for the restriction at karyn (with clearance to 12000' after karyn), la center reported traffic at 1 O'clock, 2 mi, sebnd, altitude unknown. There was a cloud in that vicinity, obscuring our vision. We kept our eyes out anyway, and from behind this cloud came an small aircraft (I think), 12 O'clock moving to 11 O'clock, slightly above us. It passed our left side in the vicinity of karyn, within 500' horizontal and vertical. We determined evasive action was not required, but the small aircraft seemed to take a left turn as we came into view. That action actually took him a bit closer to us. It appeared the small aircraft did not have 200' horizontal clearance from the clouds. The small aircraft pilot may have had difficulty judging our altitude and angle of closure. Had the small aircraft been a mile beyond karyn, we probably would have climbed right into it. We definitely need altitude encoding on all aircraft in the la basin.

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Original NASA ASRS Text

Title: CLOSE PROX ACR-MLG GA-SMA 2 NM NORTH OF POM VOR. MLG ON SID FROM ONT.

Narrative: WE WERE ON THE POMONA 1 DEP FROM ONT. WX WAS BROKEN CUMULUS CLOUDS FROM 4000'-10000' MSL, WITH GOOD VIS BTWN CLOUDS. UPON OUR HDOF FROM ONT DEP CTL, AS WE WERE LEVELING OFF AT 7000' OVER POM FOR THE RESTRICTION AT KARYN (WITH CLRNC TO 12000' AFTER KARYN), LA CENTER RPTED TFC AT 1 O'CLOCK, 2 MI, SEBND, ALT UNKNOWN. THERE WAS A CLOUD IN THAT VICINITY, OBSCURING OUR VISION. WE KEPT OUR EYES OUT ANYWAY, AND FROM BEHIND THIS CLOUD CAME AN SMA (I THINK), 12 O'CLOCK MOVING TO 11 O'CLOCK, SLIGHTLY ABOVE US. IT PASSED OUR LEFT SIDE IN THE VICINITY OF KARYN, WITHIN 500' HORIZ AND VERT. WE DETERMINED EVASIVE ACTION WAS NOT REQUIRED, BUT THE SMA SEEMED TO TAKE A LEFT TURN AS WE CAME INTO VIEW. THAT ACTION ACTUALLY TOOK HIM A BIT CLOSER TO US. IT APPEARED THE SMA DID NOT HAVE 200' HORIZ CLRNC FROM THE CLOUDS. THE SMA PLT MAY HAVE HAD DIFFICULTY JUDGING OUR ALT AND ANGLE OF CLOSURE. HAD THE SMA BEEN A MILE BEYOND KARYN, WE PROBABLY WOULD HAVE CLBED RIGHT INTO IT. WE DEFINITELY NEED ALT ENCODING ON ALL ACFT IN THE LA BASIN.

Data retrieved from NASA's ASRS site as of August 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.