Narrative:

A cessna appeared through the windshield from behind my r-hand window post, slightly above my assigned altitude of 4000 ft. I was on a 240 degree heading, tracking 246 degrees, and the cessna was on a course approximately 90 degrees to my heading. I evaded the other aircraft with a descending right turn behind it. Upon reporting the occurrence to approach control, the controller replied he had a primary target but did not know who it was. I acknowledged it to be ok, as I had avoided the other airplane by diving. I must be more suspicious of possible uncalled traffic while on an IFR clearance in clear WX, especially when flying slightly above a class D traffic area (the 3800 ft class D ceiling may have contributed to the other aircraft flying eastbound at 4000 ft to avoid class D communication.)

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Original NASA ASRS Text

Title: AN IFR PVT PLT DIVES AND TURNS TO AVOID A CESSNA TYPE ACFT THAT CREATED AN NMAC AT 4000 FT E OF MFD, OH.

Narrative: A CESSNA APPEARED THROUGH THE WINDSHIELD FROM BEHIND MY R-HAND WINDOW POST, SLIGHTLY ABOVE MY ASSIGNED ALT OF 4000 FT. I WAS ON A 240 DEG HDG, TRACKING 246 DEGS, AND THE CESSNA WAS ON A COURSE APPROX 90 DEGS TO MY HDG. I EVADED THE OTHER ACFT WITH A DSNDING R TURN BEHIND IT. UPON RPTING THE OCCURRENCE TO APCH CTL, THE CTLR REPLIED HE HAD A PRIMARY TARGET BUT DID NOT KNOW WHO IT WAS. I ACKNOWLEDGED IT TO BE OK, AS I HAD AVOIDED THE OTHER AIRPLANE BY DIVING. I MUST BE MORE SUSPICIOUS OF POSSIBLE UNCALLED TFC WHILE ON AN IFR CLRNC IN CLR WX, ESPECIALLY WHEN FLYING SLIGHTLY ABOVE A CLASS D TFC AREA (THE 3800 FT CLASS D CEILING MAY HAVE CONTRIBUTED TO THE OTHER ACFT FLYING EBOUND AT 4000 FT TO AVOID CLASS D COM.)

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.