Narrative:

Day VFR; cavu pleasure flight; flying level at 2000 ft MSL (1200 ft AGL) on an approximately magnetic heading of 030 degrees. To avoid the sts class D airspace; approximately position was the sts 105 degree radial 6.5 DME. My peripheral vision caught an aircraft off my right wing at a near 90 degree crossing angle to our flight path and near level with our altitude (within 25 ft). I pulled back on the stick hard to gain separation. Time from sighting to crossing was no more than 2 seconds with an estimate clearance of no more than 40 ft. The second aircraft was a piper comanche inbound to sonoma county airport. While I hesitate to say this aircraft did not have me in sight; it is extremely unlikely that he would not have seen a highly polished aircraft filling up his windshield from some distance away whether this was an intentional maneuver I do not know.

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Original NASA ASRS Text

Title: LUSCOMBE PLT RPTS NMAC WITH PIPER COMANCHE; 6 MI SE OF STS AT 2000 FT.

Narrative: DAY VFR; CAVU PLEASURE FLT; FLYING LEVEL AT 2000 FT MSL (1200 FT AGL) ON AN APPROX MAGNETIC HDG OF 030 DEGS. TO AVOID THE STS CLASS D AIRSPACE; APPROX POS WAS THE STS 105 DEG RADIAL 6.5 DME. MY PERIPHERAL VISION CAUGHT AN ACFT OFF MY R WING AT A NEAR 90 DEG XING ANGLE TO OUR FLT PATH AND NEAR LEVEL WITH OUR ALT (WITHIN 25 FT). I PULLED BACK ON THE STICK HARD TO GAIN SEPARATION. TIME FROM SIGHTING TO XING WAS NO MORE THAN 2 SECONDS WITH AN ESTIMATE CLRNC OF NO MORE THAN 40 FT. THE SECOND ACFT WAS A PIPER COMANCHE INBOUND TO SONOMA COUNTY ARPT. WHILE I HESITATE TO SAY THIS ACFT DID NOT HAVE ME IN SIGHT; IT IS EXTREMELY UNLIKELY THAT HE WOULD NOT HAVE SEEN A HIGHLY POLISHED ACFT FILLING UP HIS WINDSHIELD FROM SOME DISTANCE AWAY WHETHER THIS WAS AN INTENTIONAL MANEUVER I DO NOT KNOW.

Data retrieved from NASA's ASRS site as of January 2009 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.