Narrative:

IFR flight plan in VMC under dover control. Traffic called at 7 miles at ten o'clock and I called that I saw it. Traffic was squawking mode C and was called at 4;100 feet; I was at 4;000 feet. Traffic heading northwest. I was on V16 heading southwest. I let traffic get close; but at one point I decided to dive the aircraft rapidly to 3;200 feet and turned to keep eyes on the other aircraft...informed ATC of maneuver and that 'that was close.' other aircraft never took any action. Climbed back to 4;000 feet and continued flight without further event. The other aircraft was not at proper VFR cruise altitude.

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Original NASA ASRS Text

Title: P28A pilot reported he took evasive action and dove to avoid an aircraft he perceived to be a collision threat.

Narrative: IFR flight plan in VMC under Dover control. Traffic called at 7 miles at ten o'clock and I called that I saw it. Traffic was squawking Mode C and was called at 4;100 feet; I was at 4;000 feet. Traffic heading northwest. I was on V16 heading southwest. I let traffic get close; but at one point I decided to dive the aircraft rapidly to 3;200 feet and turned to keep eyes on the other aircraft...informed ATC of maneuver and that 'that was close.' Other aircraft never took any action. Climbed back to 4;000 feet and continued flight without further event. The other aircraft was not at proper VFR cruise altitude.

Data retrieved from NASA's ASRS site as of July 2013 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.