On September 15, 2000, at 1100 hours mountain standard time, a Piper PA-28-161, N381AS, experienced a loss of engine power during the takeoff initial climb from runway 7L at the Deer Valley Airport, Phoenix, Arizona. During an attempted return to runway maneuver the airplane struck a perimeter fence, and came to rest inverted at the departure end of the runway. The airplane was operated by DEV Holdings, d.b.a. Pan Am International Flight Academy, under the provisions of 14 CFR Part 91, and sustained substantial damage. The certified flight instructor (CFI) and student pilot were not injured. Visual meteorological conditions existed for the local area instructional flight, and no flight plan was filed. In an interview with a Federal Aviation Administration inspector, the CFI stated that after takeoff a loss of power was experienced. He took the controls from the student, and attempted to turn back to the runway for landing but had insufficient altitude to make the landing surface. In the CFI's written statement, he reported that during the preflight the student noted that the airplane was low on fuel. After the airplane was refueled, the CFI strained fuel from the fuel sumps with no anomalies noted. He further stated that there were no discrepancies noted with the startup, run-up or pretakeoff checklists. After receiving takeoff clearance, the student pilot advanced the throttles with no "unusual indications from the engine instruments" noted by the CFI. He estimated that at 100 feet agl the engine began to sputter. He took the controls from the student and checked that the fuel pump was on. He also verified that the throttle was full forward, and the mixture was rich. He heard the engine sputter again, which he attributed to a fuel related issue. He saw the fuel pressure gage indicating zero and rechecked that the fuel pump was on. He transmitted a mayday call to the tower and began a turn back to the runway. In the turn the airplane lost altitude. As the pilot returned the airplane to a wings level flight attitude he noted that the airport perimeter fence was in front of them. The airplane struck the perimeter fence and came to rest upside down. He asked if his student was okay. The CFI shut the airplane down and they evacuated the airplane. In the student pilot's written statement he reported the engine instruments were indicating normal and no discrepancies were noted with the takeoff. When he noted the power loss, he gave control of the airplane to his instructor. He reported that his instructor attempted resolve the problem and then made the mayday call. The power plant was inspected at Air Transport in Phoenix on October 11, 2000, by a Safety Board investigator with a representative from Textron Lycoming engines, who was a party to the investigation. A visual inspection was conducted, with no discrepancies noted. A remote fuel source was attached to the fuel line of the left wing to facilitate an engine run-up. The electric fuel pump was activated via a switch in the cockpit and fuel pressure was observed on the fuel pressure gage. No visible fuel leaks were observed coming from the engine. The engine was started per the manufacturer's checklist. After the engine was warmed up the throttles were advanced to full power with no discrepancies noted. A magneto check was conducted and found to be within manufacturer's limits.