Narrative:

Climbing out of lax, we were cleared to FL310. Climbing through FL290, we were nose-to-nose with another B737 that was level at FL290. I saw the traffic on TCASII at 15 mi range, we were nose-to-nose at FL290. We were closing very rapidly. I called ZLA 126.52 to ask about the traffic. Just as I was asking about the traffic, the TCASII went off with an RA 'climb.' green DOT up about 1800 FPM to 2000 FPM, which we did. Center said to turn left to a heading of 250 degrees. All of the above happened at the same time. We were IMC at the time and never saw the other jet. We really yanked and banked. ATC caused this event. TCASII worked as advertised, crew worked as advertised. This all happened very, very fast. Supplemental information from acn 566902: TCASII RA, near midair collision. Climbing through FL285 for FL310, another aircraft popped up on TCASII at same altitude. Immediately got RA 'climb, climb.' captain verified maximum power, and I started turn towards left. Controller gave new heading of 250 degrees (approximately 40 degrees off heading). Captain inquired as to traffic. Controller stated that other traffic had penetrated our airspace. Remainder of flight was uneventful. This event happened very quickly. I believe we were within 5 seconds of a head-on. The TCASII worked perfectly. We were within approximately 4 mi head-on with the aircraft.

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Original NASA ASRS Text

Title: B737 CREW OUT OF LAX CLBING THROUGH FL285 FOR FL310 ENCOUNTER OPPOSITE DIRECTION TFC AT FL290 REQUIRING AN EVASIVE ACTION MANEUVER.

Narrative: CLBING OUT OF LAX, WE WERE CLRED TO FL310. CLBING THROUGH FL290, WE WERE NOSE-TO-NOSE WITH ANOTHER B737 THAT WAS LEVEL AT FL290. I SAW THE TFC ON TCASII AT 15 MI RANGE, WE WERE NOSE-TO-NOSE AT FL290. WE WERE CLOSING VERY RAPIDLY. I CALLED ZLA 126.52 TO ASK ABOUT THE TFC. JUST AS I WAS ASKING ABOUT THE TFC, THE TCASII WENT OFF WITH AN RA 'CLB.' GREEN DOT UP ABOUT 1800 FPM TO 2000 FPM, WHICH WE DID. CTR SAID TO TURN L TO A HDG OF 250 DEGS. ALL OF THE ABOVE HAPPENED AT THE SAME TIME. WE WERE IMC AT THE TIME AND NEVER SAW THE OTHER JET. WE REALLY YANKED AND BANKED. ATC CAUSED THIS EVENT. TCASII WORKED AS ADVERTISED, CREW WORKED AS ADVERTISED. THIS ALL HAPPENED VERY, VERY FAST. SUPPLEMENTAL INFO FROM ACN 566902: TCASII RA, NMAC. CLBING THROUGH FL285 FOR FL310, ANOTHER ACFT POPPED UP ON TCASII AT SAME ALT. IMMEDIATELY GOT RA 'CLB, CLB.' CAPT VERIFIED MAX PWR, AND I STARTED TURN TOWARDS L. CTLR GAVE NEW HDG OF 250 DEGS (APPROX 40 DEGS OFF HDG). CAPT INQUIRED AS TO TFC. CTLR STATED THAT OTHER TFC HAD PENETRATED OUR AIRSPACE. REMAINDER OF FLT WAS UNEVENTFUL. THIS EVENT HAPPENED VERY QUICKLY. I BELIEVE WE WERE WITHIN 5 SECONDS OF A HEAD-ON. THE TCASII WORKED PERFECTLY. WE WERE WITHIN APPROX 4 MI HEAD-ON WITH THE ACFT.

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.