Narrative:

While in VMC on an IFR flight plan, on V139 between sie and swl, my clearance was changed to direct swl direct ccv. I re-centered the obs and altered course slightly. Shortly after passing swl, the controller informed me that I had entered R6604 and gave me a heading to fly with an immediate right turn. The restr area was hot. There was light turbulence. I looked down to figure out why I was off course, and found that in the turbulence I had hit the 'automatic center' on my cessna 408 series radios, and had turned to keep it centered. Pilot error induced by the turbulence and complacency due to VMC.

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Original NASA ASRS Text

Title: A C401 PLT WANDERS INTO R6604 AFTER MISUSING HIS NAV RADIO IN CONJUNCTION WITH THE OMNI BEARING SELECTOR S OF SWL, MD.

Narrative: WHILE IN VMC ON AN IFR FLT PLAN, ON V139 BTWN SIE AND SWL, MY CLRNC WAS CHANGED TO DIRECT SWL DIRECT CCV. I RE-CTRED THE OBS AND ALTERED COURSE SLIGHTLY. SHORTLY AFTER PASSING SWL, THE CTLR INFORMED ME THAT I HAD ENTERED R6604 AND GAVE ME A HDG TO FLY WITH AN IMMEDIATE R TURN. THE RESTR AREA WAS HOT. THERE WAS LIGHT TURB. I LOOKED DOWN TO FIGURE OUT WHY I WAS OFF COURSE, AND FOUND THAT IN THE TURB I HAD HIT THE 'AUTO CTR' ON MY CESSNA 408 SERIES RADIOS, AND HAD TURNED TO KEEP IT CTRED. PLT ERROR INDUCED BY THE TURB AND COMPLACENCY DUE TO VMC.

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.