Flight and Engine Malfunction
A cross-country flight was conducted at 4500 feet. The engine began sputtering, prompting the pilot to adjust the mixture and apply carburetor heat, though reportedly for only a short time. The engine continued operating at reduced power.
Descent and Pilot Actions
The aircraft lost altitude and descended into clouds. The pilot was able to level the aircraft at approximately 500 feet above ground level (AGL). He elected to divert, contacted the Wausau (AUW) Flight Service Station (FSS), declared an emergency, and requested assistance.
Communication with Flight Service
The FSS had no direction-finding equipment. The aircraft was too low for radar identification, and its automatic direction finder (ADF) was inoperative. Uncertain of his position, the pilot received assistance from the FSS specialist, who attempted VOR orientation procedures.
Navigation Misidentification
The pilot tuned in the Stevens Point (STE) VOR and reported a heading of 10 degrees, presumably toward the VOR. The FSS specialist erroneously informed the pilot that he was between the STE VOR and the AUW VOR, when in fact the aircraft was south of both VORs and close to the Stevens Point airport. The specialist then instructed the pilot to fly to the AUW VOR, located north of STE.
After the aircraft passed north of STE, the specialist identified its position near a lake just south of AUW and advised the pilot to continue toward the VOR. Moments before radio contact was lost, the pilot reported a bearing of 011 degrees to the VOR station.
Collision and Findings
The aircraft struck trees near a mountaintop approximately 7 miles northwest of the VOR. No pre-impact mechanical problems were found. Carburetor icing conditions were reported.