On August 31, 2004, at 1030 eastern daylight time, N123LZ, an experimental PZL 101 airplane, was substantially damaged during a forced landing, following a loss of power near Chazy, New York. The certificated commercial pilot was not injured. Visual meteorological conditions prevailed and no flight plan was filed for the flight which originated at a private airstrip in Swanton, Vermont, and was destined for the Upper Cumberland Regional Airport (SRB), Sparta, Tennessee. The personal flight was conducted under 14 CFR Part 91. The pilot reported that approximately 20 minutes after takeoff, the engine "locked up" without warning. The pilot performed a forced landing to a field, and during the landing, the airplane impacted a ditch, substantially damaging the airplane. Examination of the radial engine by a Federal Aviation Administration (FAA) inspector revealed that the crankshaft was fractured. Additionally, as the inspector rotated the propeller, an "audible crunching sound" was heard from the accessory gearbox. Fuel was observed in both fuel tanks and fuel continuity was confirmed to the engine. The oil sump was empty; however, a significant amount of oil was observed under the engine. Additionally, the oil tank was ruptured, and the amount of oil could not be determined.