Narrative:

Shortly after takeoff from ont we were cleared to 14000' MSL. We were on an assigned heading of 100 degrees to join the trm 263 degree right. Passing through approximately 12000' center called out a traffic alert at 12 O'clock, less than 1 mi, at 12500'. We leveled off at approximately 12200' MSL and picked up the other aircraft (a bi-colored turbo-propeller at our altitude). The turboprop made an immediate right turn and so did we, passing within 500' of each other. The controller apologized for not picking it up sooner and we continued the remainder of the flight west/O incident. Supplemental information from acn 140673: approaching 12000' ATC told us to level at present altitude cancelling our clearance to 17000'. We were told we had traffic at our 11 O'clock, less than 1 mi passing through 12500'. We then heard our traffic being told to make an immediate hard turn to the north. Upon sighting our traffic in a nose down hard bank we began a turn to our right and notified the controller of that fact. We had managed to level off at 12200'. I estimate that we passed each other about 500' sep and had not the other aircraft been told to make a hard turn we would have possibly hit.

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Original NASA ASRS Text

Title: FLT CREW OF ACR MLG DEPARTING ONT HAVE NMAC WHILE ON THE PRADO 2 DEP WITH A CORP TURBO PROP ALSO IN CONTACT WITH ATC.

Narrative: SHORTLY AFTER TKOF FROM ONT WE WERE CLRED TO 14000' MSL. WE WERE ON AN ASSIGNED HDG OF 100 DEGS TO JOIN THE TRM 263 DEG R. PASSING THROUGH APPROX 12000' CENTER CALLED OUT A TFC ALERT AT 12 O'CLOCK, LESS THAN 1 MI, AT 12500'. WE LEVELED OFF AT APPROX 12200' MSL AND PICKED UP THE OTHER ACFT (A BI-COLORED TURBO-PROP AT OUR ALT). THE TURBOPROP MADE AN IMMEDIATE RIGHT TURN AND SO DID WE, PASSING WITHIN 500' OF EACH OTHER. THE CTLR APOLOGIZED FOR NOT PICKING IT UP SOONER AND WE CONTINUED THE REMAINDER OF THE FLT W/O INCIDENT. SUPPLEMENTAL INFO FROM ACN 140673: APCHING 12000' ATC TOLD US TO LEVEL AT PRESENT ALT CANCELLING OUR CLRNC TO 17000'. WE WERE TOLD WE HAD TFC AT OUR 11 O'CLOCK, LESS THAN 1 MI PASSING THROUGH 12500'. WE THEN HEARD OUR TFC BEING TOLD TO MAKE AN IMMEDIATE HARD TURN TO THE N. UPON SIGHTING OUR TFC IN A NOSE DOWN HARD BANK WE BEGAN A TURN TO OUR RIGHT AND NOTIFIED THE CTLR OF THAT FACT. WE HAD MANAGED TO LEVEL OFF AT 12200'. I ESTIMATE THAT WE PASSED EACH OTHER ABOUT 500' SEP AND HAD NOT THE OTHER ACFT BEEN TOLD TO MAKE A HARD TURN WE WOULD HAVE POSSIBLY HIT.

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.