Narrative:

During cruise flight level at 5500 ft MSL, and while aggressively scanning the vicinity for other aircraft, noticed the single engine cessna on my starboard side, in a climbing turn (evasive or maneuvering) but noted no further action necessary as the C172 had been passed and we were both opening distance. Estimate approximately 300 ft horizontal separation or less and maybe 50-75 ft vertical separation. I had mode C on and had been monitoring, but not participating in advisories, but had tuned in the ATIS at fcm 30 seconds or so before the near miss occurred. The rest of the flight was uneventful and terminated normally.

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Original NASA ASRS Text

Title: NMAC BTWN A PA28 IN LEVEL FLT AT 5000 FT MSL, AND A CESSNA 172 ON THE R IN A CLBING R TURN AS IF TAKING EVASIVE ACTION.

Narrative: DURING CRUISE FLT LEVEL AT 5500 FT MSL, AND WHILE AGGRESSIVELY SCANNING THE VICINITY FOR OTHER ACFT, NOTICED THE SINGLE ENG CESSNA ON MY STARBOARD SIDE, IN A CLBING TURN (EVASIVE OR MANEUVERING) BUT NOTED NO FURTHER ACTION NECESSARY AS THE C172 HAD BEEN PASSED AND WE WERE BOTH OPENING DISTANCE. ESTIMATE APPROX 300 FT HORIZ SEPARATION OR LESS AND MAYBE 50-75 FT VERT SEPARATION. I HAD MODE C ON AND HAD BEEN MONITORING, BUT NOT PARTICIPATING IN ADVISORIES, BUT HAD TUNED IN THE ATIS AT FCM 30 SECONDS OR SO BEFORE THE NEAR MISS OCCURRED. THE REST OF THE FLT WAS UNEVENTFUL AND TERMINATED NORMALLY.

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.