Narrative:

Approximately 15 mins into flight, flight attendant reported that a passenger, who said he held a private pilot's license, thought we had an near midair collision with an aircraft above us on climb out from lax. Conditions were overcast at takeoff and our TCASII was placarded inoperative. Neither the first officer nor I had any sighting of any aircraft which was unusually close, and ATC did not issue any abrupt avoidance commands. ATC did, however, issue a couple of intermediate leveloffs and gave incremental turns back toward the shoreline. My appraisal is that there may have been traffic above us, which necessitated the resulting leveloffs and turns, but that this individual's perceptions of distance and actions were not accurate, and may have been amplified by the visual sensation of speed as we climbed out of the overcast. This person also did not identify himself or talk to me at the conclusion of the flight, so I consider this to be a non event. Supplemental information from acn 557444: we asked the flight attendant to invite the passenger to speak with us after the flight. When we deplaned, the passenger did not stop to speak with us so we were unable to gain any additional information, including his identify.

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Original NASA ASRS Text

Title: A B767 CREW, DEPARTING LAX, RECEIVED A PAX RPT FROM THE CABIN CLAIMING AN NMAC WITH ANOTHER ACFT.

Narrative: APPROX 15 MINS INTO FLT, FLT ATTENDANT RPTED THAT A PAX, WHO SAID HE HELD A PVT PLT'S LICENSE, THOUGHT WE HAD AN NMAC WITH AN ACFT ABOVE US ON CLBOUT FROM LAX. CONDITIONS WERE OVCST AT TKOF AND OUR TCASII WAS PLACARDED INOP. NEITHER THE FO NOR I HAD ANY SIGHTING OF ANY ACFT WHICH WAS UNUSUALLY CLOSE, AND ATC DID NOT ISSUE ANY ABRUPT AVOIDANCE COMMANDS. ATC DID, HOWEVER, ISSUE A COUPLE OF INTERMEDIATE LEVELOFFS AND GAVE INCREMENTAL TURNS BACK TOWARD THE SHORELINE. MY APPRAISAL IS THAT THERE MAY HAVE BEEN TFC ABOVE US, WHICH NECESSITATED THE RESULTING LEVELOFFS AND TURNS, BUT THAT THIS INDIVIDUAL'S PERCEPTIONS OF DISTANCE AND ACTIONS WERE NOT ACCURATE, AND MAY HAVE BEEN AMPLIFIED BY THE VISUAL SENSATION OF SPD AS WE CLBED OUT OF THE OVCST. THIS PERSON ALSO DID NOT IDENT HIMSELF OR TALK TO ME AT THE CONCLUSION OF THE FLT, SO I CONSIDER THIS TO BE A NON EVENT. SUPPLEMENTAL INFO FROM ACN 557444: WE ASKED THE FLT ATTENDANT TO INVITE THE PAX TO SPEAK WITH US AFTER THE FLT. WHEN WE DEPLANED, THE PAX DID NOT STOP TO SPEAK WITH US SO WE WERE UNABLE TO GAIN ANY ADDITIONAL INFO, INCLUDING HIS IDENT.

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.