Narrative:

While on right downwind leg for landing on runway 16L at sea we received a RA on the TCASII. We were in level flight on a heading of approximately 340 degrees at 11000 ft MSL. The advisory indicated a target at approximately our 2 O'clock position with a relative altitude of 200 ft below us. It commanded a 'climb- climb.' it continued to command this until a second target Y was acquired above us and the advisory changed to 'climb- crossing-climb.' the climb was continued until 'clear of conflict' was annunciated at 13000 ft MSL. At that time a descent back to the assigned altitude was initiated. We were not advised by ATC of either traffic conflict, but ATC did request an immediate left turn at the time the second RA was received. The first officer was flying the aircraft except for a brief period when I took control when the immediate left turn was requested. A dead-heading pilot sitting on the right side of the aircraft acquired the first target visually and stated that he estimated horizontal separation was less than 1/2 mi. The flight crew did not acquire either target visually.

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Original NASA ASRS Text

Title: ACR X TCASII RA CLB NON ADHERENCE TO ATC CLRNC HAD CONFLICT WITH ACFT Y. PLTDEV.

Narrative: WHILE ON R DOWNWIND LEG FOR LNDG ON RWY 16L AT SEA WE RECEIVED A RA ON THE TCASII. WE WERE IN LEVEL FLT ON A HDG OF APPROX 340 DEGS AT 11000 FT MSL. THE ADVISORY INDICATED A TARGET AT APPROX OUR 2 O'CLOCK POS WITH A RELATIVE ALT OF 200 FT BELOW US. IT COMMANDED A 'CLB- CLB.' IT CONTINUED TO COMMAND THIS UNTIL A SECOND TARGET Y WAS ACQUIRED ABOVE US AND THE ADVISORY CHANGED TO 'CLB- XING-CLB.' THE CLB WAS CONTINUED UNTIL 'CLR OF CONFLICT' WAS ANNUNCIATED AT 13000 FT MSL. AT THAT TIME A DSCNT BACK TO THE ASSIGNED ALT WAS INITIATED. WE WERE NOT ADVISED BY ATC OF EITHER TFC CONFLICT, BUT ATC DID REQUEST AN IMMEDIATE L TURN AT THE TIME THE SECOND RA WAS RECEIVED. THE FO WAS FLYING THE ACFT EXCEPT FOR A BRIEF PERIOD WHEN I TOOK CTL WHEN THE IMMEDIATE L TURN WAS REQUESTED. A DEAD-HDG PLT SITTING ON THE R SIDE OF THE ACFT ACQUIRED THE FIRST TARGET VISUALLY AND STATED THAT HE ESTIMATED HORIZ SEPARATION WAS LESS THAN 1/2 MI. THE FLC DID NOT ACQUIRE EITHER TARGET VISUALLY.

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.