On August 12, 2009, about 1010 mountain standard time (MST), a Piper PA-38-112, N86GW, made a forced landing following a loss of engine power near Glendale Municipal Airport, Glendale, Arizona. The student pilot, who is also the owner, was operating the airplane under the provisions of 14 Code of Federal Regulations (CFR) Part 91. The student pilot was not injured; the airplane sustained substantial damage to the left wing. The local instructional flight departed Phoenix, Arizona, about 0930. Visual meteorological conditions prevailed, and no flight plan had been filed. The student pilot reported that after completing his seventh touch-and-go, and on the upwind leg after reaching 400-500 feet above ground level (agl), the engine lost power. He attempted to restart the engine but was unsuccessful. During the forced landing onto a dirt field, the outboard section of the left wing was damaged. The student pilot stated he had recently purchased the airplane from the estate of the previous owner. The airplane was recovered from the dirt parking lot for further examination. On August 19, 2009, an examination of the airplane was conducted by FAA inspectors at Air Transport, Inc., Phoenix. The engine was started and ran smoothly for about 5 minutes. No preexisting mechanical anomalies were noted with the examination of the recovered airframe and engine that would have precluded normal operation.