C182RG PLT HAS NAV PROB AND POSSIBLY ENTERS A RESTR AREA. ALSO DEVIATING WX.

Narrative

AFTER DEPARTING APPLETON I CONTACTED GREEN BAY APCH FOR TFC AND WAS NEVER TERMINATED. I FLEW A HDG OF 267 DEGS AND REMAINED N OF THE OSH 287 DEG RADIAL (BOTH VOR RECEIVERS) TO REMAIN CLR OF R6904A. HOWEVER; AT 65 MI DME; MY LORAN C INDICATED 1 MI PENETRATION INTO R6904A. I TURNED N UNTIL THE LORAN C INDICATED WELL CLR. SUBSEQUENTLY I ENCOUNTERED A RISING UNDERCAST AND TURNED TO A HDG OF 245 DEGS TO REMAIN N OF GBR 260 DEG RADIAL. AGAIN WHEN PASSING R6901A MY LORAN C INDICATED A 2 MI PENETRATION INTO THE RESTR AREA. I IMMEDIATELY TURNED NW TO EXIT. I SUBSEQUENTLY CHKED BOTH VORS FOR RADIAL DEV BUT BOTH APPEARED ACCURATE. THE LORAN C ALSO CHKED NORMAL. AT THIS STAGE; I AM NOT SURE WHETHER I ACTUALLY ENTERED THE RESTR AREAS OR NOT. IF SO; A CONTRIBUTING FACTOR WAS CONCERN ABOUT THE OBSERVED DETERIORATING WX SIT AHEAD ALONG OUR TRACK. I ALSO HAD THE ACFT ON AUTOPLT SLAVED TO THE LORAN C TRACK DIRECT TO MANKATO; MN; WHICH WAS AN INTENDED FUEL STOP. THE HDG WAS 267 DEGS AS PER THE LORAN C CALCULATION.