The airplane impacted terrain during a forced landing at about 1430 Mountain time. The solo commercial pilot was not injured, but the airplane sustained substantial damage. Visual conditions prevailed. While in cruise flight, the pilot suddenly heard/felt a solid “thump” appearing to come from the engine compartment. Soon thereafter, oil pressure started to drop and the engine seemed to be losing power. About two minutes after the oil pressure started dropping, the engine began making a knocking sound and the propeller began to slow. Eventually the engine stopped producing any power, and the pilot attempted a forced landing on a narrow dirt road in remote terrain. Although the touchdown was successful, the pilot was unable to keep the airplane aligned with the road, and it departed the road surface and went into the nearby rough/uneven terrain.
