20010503030869A

(.4) According to the flight instructor and pilot receiving instruction, the student was demonstrating a commercial flight maneuver, at 2,100 feet AGL, when they smelled an odor similar to "electrical burning." The instructor told the student to terminate the maneuver and return to the airport. While the student was terminating the maneuver, visible smoke appeared in the cabin, and heat was felt coming from beneath the instrument panel. The instructor assumed control of the airplane. The engine was shut down and a forced landing was executed to a field. During the landing, the airplane encountered soft terrain, nosed over and came to rest inverted. A plastic hydraulic reservoir, from the hydraulic power pack, was found melted and laying on the cockpit floor. The hydraulic power pack was examined and functionally tested at aero electric inc., wichita, Kansas, under supervision of the FAA. According a report from aero electric, the power pack and its related components operated within manufacturer's specifications. (.19) on may 3, 2001, at 1315 central daylight time, a Cessna 172RG, airplane, N9696B, was substantially damaged during a precautionary landing near w ashington, Oklahoma. The airplane was registered to christensen aviation inc., of wilmington, Delaware, and operated by airman flight school, inc., of norman, Oklahoma. The flight instructor and private pilot receiving instruction received minor injuries. Visual meteorological conditions prevailed and flight plan was not filed for the 14 code of federal regulations part 91 instructional flight. The local flight originated from the university of Oklahoma westheimer airport, norman, Oklahoma. According to personnel at airman flight school, the instructor pilot and pilot receiving instruction were practicing commercial flight maneuvers at 2,100 feet AGL, when they smelled an odor similar to "electrical burning." They terminated the maneuver and initiated the return flight to the airport. Approximately two minutes later the cockpit area filled with smoke. All pertinent equipment was secured and a precautionary landing was executed to a field. During the landing the airplane nosed over and came to rest inverted. According to the FAA inspector, who examined the airplane, he observed chaffing of electrical wires between the engine firewall and cockpit instrument panel. A plastic hydraulicreservoir was found melted and laying on the cockpit floor. He stated that the left wing-tip, the right wing strut, and the tail section were structurally damaged. He added that the engine firewall was buckled. (-23) this was an instructional flight. Aircraft departed norman, Oklahoma (oun), southbound to training area. Pilot was practicing 8'S on pylons when they smelled electrical wire burning. Instructor made decision to return to norman, Oklahoma, when smoke filled the cockpit and area by rudder pedals became very hot. Instructor made decision to make emergency landing off airport resulting in substantial damage to aircraft. Pilots walked to private residence and called authorities.