Narrative:

Prado 2 departure from ont, left turn direct pdz. Assigned altitude 7000 ft. Initial contact with ont departure, controller issued new altitude assignment of 3000 ft as were climbing through 2700 ft, and called traffic at 12 O'clock, 4000 ft, that he 'wasn't talking to.' simultaneously, TCASII annunciated RA 12 O'clock within 5 mi with no previous TA, then failed and went blank, annunciating no TCASII. While continuing SID turn direct pdz we observed traffic at 12 O'clock and continued left turn approximately 30 degree further to avoid traffic. Recycled TCASII to TA several times to reinstate. Unable to advise ATC of deviation as frequency very congested. Controller still trying to contact the initial called aircraft at 12 O'clock. While initiating turn back towards pdz, ATC assigned heading 180 degree and 4200 ft, then 7000 ft. While climbing through 6500 ft received another TCASII RA with descent annunciated. We followed RA commands when controller asked why we made wide left turn. I asked him to standby. After we had resolved RA, I explained we just had RA with previous RA earlier, and apologized for deviation. Supervisor requested we call ont TRACON upon landing, which I did. Situation appeared resolved with both of us agreeing an earlier call to ATC would have been helpful. Contributing factors were immediate level off, controller called traffic at 12 O'clock with no contact, TCASII warning and subsequent failure, and congested frequency. Supervisor stated problem was turning toward ont approach traffic, but since we were already in left turn, right turn seemed unadvisable. No conflict was reported.

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Original NASA ASRS Text

Title: FLC OF ACR MLG ACFT DEVIATED FROM ASSIGNED HDG IN RESPONSE TO A TCASII RA DURING A SID CLBOUT.

Narrative: PRADO 2 DEP FROM ONT, L TURN DIRECT PDZ. ASSIGNED ALT 7000 FT. INITIAL CONTACT WITH ONT DEP, CTLR ISSUED NEW ALT ASSIGNMENT OF 3000 FT AS WERE CLBING THROUGH 2700 FT, AND CALLED TFC AT 12 O'CLOCK, 4000 FT, THAT HE 'WASN'T TALKING TO.' SIMULTANEOUSLY, TCASII ANNUNCIATED RA 12 O'CLOCK WITHIN 5 MI WITH NO PREVIOUS TA, THEN FAILED AND WENT BLANK, ANNUNCIATING NO TCASII. WHILE CONTINUING SID TURN DIRECT PDZ WE OBSERVED TFC AT 12 O'CLOCK AND CONTINUED L TURN APPROX 30 DEG FURTHER TO AVOID TFC. RECYCLED TCASII TO TA SEVERAL TIMES TO REINSTATE. UNABLE TO ADVISE ATC OF DEV AS FREQ VERY CONGESTED. CTLR STILL TRYING TO CONTACT THE INITIAL CALLED ACFT AT 12 O'CLOCK. WHILE INITIATING TURN BACK TOWARDS PDZ, ATC ASSIGNED HDG 180 DEG AND 4200 FT, THEN 7000 FT. WHILE CLBING THROUGH 6500 FT RECEIVED ANOTHER TCASII RA WITH DSCNT ANNUNCIATED. WE FOLLOWED RA COMMANDS WHEN CTLR ASKED WHY WE MADE WIDE L TURN. I ASKED HIM TO STANDBY. AFTER WE HAD RESOLVED RA, I EXPLAINED WE JUST HAD RA WITH PREVIOUS RA EARLIER, AND APOLOGIZED FOR DEV. SUPVR REQUESTED WE CALL ONT TRACON UPON LNDG, WHICH I DID. SITUATION APPEARED RESOLVED WITH BOTH OF US AGREEING AN EARLIER CALL TO ATC WOULD HAVE BEEN HELPFUL. CONTRIBUTING FACTORS WERE IMMEDIATE LEVEL OFF, CTLR CALLED TFC AT 12 O'CLOCK WITH NO CONTACT, TCASII WARNING AND SUBSEQUENT FAILURE, AND CONGESTED FREQ. SUPVR STATED PROBLEM WAS TURNING TOWARD ONT APCH TFC, BUT SINCE WE WERE ALREADY IN L TURN, R TURN SEEMED UNADVISABLE. NO CONFLICT WAS RPTED.

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.