Narrative:

While first officer was thanking passenger during deplaning, a male passenger briefly asked the first officer, 'will the FAA count that B747 near us as a near miss?' the first officer responded that we were unaware of any aircraft in close proximity to us. He further told the first officer that it occurred at XA50Z and would write a letter to the FAA regarding this. When the first officer advised me of this conversation, I, like him, was surprised to hear this since we did not see this traffic, we were not advised by ATC, nor did we hear an air carrier X call sign on the radio. Additionally, there were no TCASII advisories or RA's. Our in-time at mem was XD22Z. According to the passenger observation of XA50Z, we would have been at cruise FL350 between hvq and bwg. The only event that occurred during this completely normal and uneventful flight was during a frequency handoff, ZID greeted us with a left 10 degree turn off course for approximately 10 mins. This occurred northeast of bwg. No traffic was issued at this time or reason for the turn. No other passenger or crew mentioned this event.

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Original NASA ASRS Text

Title: PAX ADVISED FLC AFTER LNDG THAT THEY HAD AN NMAC WITH A B747. NO SUPPORTING FACTS, TCASII, ATC OR VISUAL.

Narrative: WHILE FO WAS THANKING PAX DURING DEPLANING, A MALE PAX BRIEFLY ASKED THE FO, 'WILL THE FAA COUNT THAT B747 NEAR US AS A NEAR MISS?' THE FO RESPONDED THAT WE WERE UNAWARE OF ANY ACFT IN CLOSE PROX TO US. HE FURTHER TOLD THE FO THAT IT OCCURRED AT XA50Z AND WOULD WRITE A LETTER TO THE FAA REGARDING THIS. WHEN THE FO ADVISED ME OF THIS CONVERSATION, I, LIKE HIM, WAS SURPRISED TO HEAR THIS SINCE WE DID NOT SEE THIS TFC, WE WERE NOT ADVISED BY ATC, NOR DID WE HEAR AN ACR X CALL SIGN ON THE RADIO. ADDITIONALLY, THERE WERE NO TCASII ADVISORIES OR RA'S. OUR IN-TIME AT MEM WAS XD22Z. ACCORDING TO THE PAX OBSERVATION OF XA50Z, WE WOULD HAVE BEEN AT CRUISE FL350 BTWN HVQ AND BWG. THE ONLY EVENT THAT OCCURRED DURING THIS COMPLETELY NORMAL AND UNEVENTFUL FLT WAS DURING A FREQ HDOF, ZID GREETED US WITH A L 10 DEG TURN OFF COURSE FOR APPROX 10 MINS. THIS OCCURRED NE OF BWG. NO TFC WAS ISSUED AT THIS TIME OR REASON FOR THE TURN. NO OTHER PAX OR CREW MENTIONED THIS EVENT.

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.