Narrative:

En route to san from lax we were level at 11000 when coast approach (128.10) called and advised us we had traffic at 12 O'clock at 10500. We looked but did not see the traffic. Shortly thereafter, a target appeared on TCASII -- 500 ft at 12 O'clock. We still did not see the traffic and the TCASII gave us a 'climb, climb.' the ivsi green bar was at 1500 ft up and the target was then at 200 ft and approximately 2 mi. I disconnected the autoplt and began a climb. ATC called and said he saw us climbing and advised us that there was an aircraft at 1 O'clock and 12000 ft. We looked and saw the traffic and, at the same time got a 'climb crossing climb' from the TCASII. I leveled at approximately 11800 ft and, at that time saw the 12 O'clock traffic passing under us. We advised ATC that we had traffic in sight and at that point we descended back to 11000 ft. We spoke with ATC and advised them that we would call in san. I did call and was advised that we had encroached on the other aircraft's airspace during our RA maneuver.

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Original NASA ASRS Text

Title: FLC OF AN LGT ACR ACFT CLBED ABOVE ASSIGNED ALT IN RESPONSE TO A TCASII RA RESULTING IN ATC INTERVENTION TO STOP CLB DUE TO ACFT ASSIGNED ALT JUST ABOVE!

Narrative: ENRTE TO SAN FROM LAX WE WERE LEVEL AT 11000 WHEN COAST APCH (128.10) CALLED AND ADVISED US WE HAD TFC AT 12 O'CLOCK AT 10500. WE LOOKED BUT DID NOT SEE THE TFC. SHORTLY THEREAFTER, A TARGET APPEARED ON TCASII -- 500 FT AT 12 O'CLOCK. WE STILL DID NOT SEE THE TFC AND THE TCASII GAVE US A 'CLB, CLB.' THE IVSI GREEN BAR WAS AT 1500 FT UP AND THE TARGET WAS THEN AT 200 FT AND APPROX 2 MI. I DISCONNECTED THE AUTOPLT AND BEGAN A CLB. ATC CALLED AND SAID HE SAW US CLBING AND ADVISED US THAT THERE WAS AN ACFT AT 1 O'CLOCK AND 12000 FT. WE LOOKED AND SAW THE TFC AND, AT THE SAME TIME GOT A 'CLB XING CLB' FROM THE TCASII. I LEVELED AT APPROX 11800 FT AND, AT THAT TIME SAW THE 12 O'CLOCK TFC PASSING UNDER US. WE ADVISED ATC THAT WE HAD TFC IN SIGHT AND AT THAT POINT WE DSNDED BACK TO 11000 FT. WE SPOKE WITH ATC AND ADVISED THEM THAT WE WOULD CALL IN SAN. I DID CALL AND WAS ADVISED THAT WE HAD ENCROACHED ON THE OTHER ACFT'S AIRSPACE DURING OUR RA MANEUVER.

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.