On September 26, 2015, about 1200 mountain daylight time, a Beech C35 airplane, N1990D, made a forced landing to a dirt road near Belen, New Mexico. The private rated pilot and three passengers were not injured and the airplane sustained substantial damage. The airplane was registered to and operated by a private individual under the provisions of 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed at the time of the accident and a flight plan was not filed. The flight originated from the Alexander Municipal Airport (E80), Belen, New Mexico, about 1100. The pilot reported that he was taking three boys scouts for a sightseeing flight. He departed to the north and completed one touch-and-go landing at the Albuquerque International Airport (ABQ), Albuquerque, New Mexico, then proceeded south toward Los Lunas, New Mexico. He also completed several basic maneuvers and initiated a descent. About 3 miles northeast of E80 the engine experienced a total loss of power and the pilot attempted to troubleshoot the issue. Unable to restart the engine, the pilot elected to land on a dirt road. The pilot noted that the airspeed was 70 mph during the emergency landing. The airplane continued on the road for about 600 ft when the left wing collided with a mesquite bush which rotated the airplane 180°. The airplane came to rest upright next to the dirt road about 1 mile north of E80. A postaccident engine examination was conducted by a local aircraft mechanic under the supervision of a Federal Aviation Administration (FAA) inspector. The FAA inspector noted that the fuel strainer and fuel inlet screen to the pressure carburetor were clogged with contaminants and there was a distinct odor of automotive fuel. The inspector added that the owner stated that he had not used automotive fuel "much" lately. The inspector noted that the engine had been modified by supplemental type certificate (STC) SE01167SE that only allowed for the use of 100LL aviation fuel. An examination of the fuel doors revealed placards indicating that unleaded automotive gasoline was approved fuel for the airplane. The pilot stated that the accident airplane had an approved automotive fuel STC in effect from March 1985 to October 2013. Since November 2013 he had used only 100LL fuel in the airplane. A review of the maintenance logbooks showed that an airframe annual inspection and engine 100-hour inspection were completed on March 14, 2015.