Narrative:

In cruise, on IFR flight plan, level at 7000 ft, approach called traffic at 6 O'clock position, climbing. A couple of mins later a king air pulled up next to me, about 100 ft off of my right wing. He rocked his wings a couple of times and then climbed away. I was surprised by him and didn't think to get his number until he pulled away. By then, all I could see was '...xx.' he was certainly close enough to easily read the number, had I not been puzzled about his intentions. I told approach about this and they asked me to phone them on the ground. Speaking with the TRACON over the phone, I was told that they had tracked him as far as they could. He never contacted them or ZOA.

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Original NASA ASRS Text

Title: NMAC IN THE CLASS E AIRSPACE NEAR MODESTO, CA.

Narrative: IN CRUISE, ON IFR FLT PLAN, LEVEL AT 7000 FT, APCH CALLED TFC AT 6 O'CLOCK POS, CLBING. A COUPLE OF MINS LATER A KING AIR PULLED UP NEXT TO ME, ABOUT 100 FT OFF OF MY R WING. HE ROCKED HIS WINGS A COUPLE OF TIMES AND THEN CLBED AWAY. I WAS SURPRISED BY HIM AND DIDN'T THINK TO GET HIS NUMBER UNTIL HE PULLED AWAY. BY THEN, ALL I COULD SEE WAS '...XX.' HE WAS CERTAINLY CLOSE ENOUGH TO EASILY READ THE NUMBER, HAD I NOT BEEN PUZZLED ABOUT HIS INTENTIONS. I TOLD APCH ABOUT THIS AND THEY ASKED ME TO PHONE THEM ON THE GND. SPEAKING WITH THE TRACON OVER THE PHONE, I WAS TOLD THAT THEY HAD TRACKED HIM AS FAR AS THEY COULD. HE NEVER CONTACTED THEM OR ZOA.

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.