On October 12, 1994 about 1227 eastern daylight time, N601AV, a Beech A36 airplane, lost engine power and was forced landed at Amityville, New York. Visual meteorological conditions existed. The certificated private pilot and the FAA Inspector were seriously injured. The airplane was substantially damaged. The flight originated at Republic Airport, Farmingdale, New York. The flight was operated under 14 CFR Part 91. The pilot was receiving a re-examination checkride by the FAA Inspector when the accident occurred. The pilot and inspector were conducting flight in the traffic pattern for runway 01 at Republic Airport. The inspector retarded the throttle to simulate a loss of engine power and afterward the throttle was advanced to increase power, but the engine did not respond. The inspector took control of the airplane and he did a forced landing in a reservoir located in a residential area, about 0.5 mile southeast of the runway. According to the pilot, the airplane was on extended downwind to the runway, just turning base leg at approximately 900 feet, when the inspector closed the throttle to idle. The pilot stated he observed manifold pressure drop below the green arc, and he started doing engine failure procedures and headed directly for the airport. He realized that he would not make the airport, so he decided to add power. The engine did not respond to throttle movement, and the inspector took controlof the airplane. The pilot reported that he switched fuel tanks per the inspector's instruction. The pilot stated that the inspector turned the fuel pump on, although the fuel pressure was in the green arc. He stated the inspector "put the aircraft into a stall and crashed the aircraft." According to the FAA inspector, when he retarded the throttle, he felt the airplane was within gliding distance to the airport. When he realized the engine power could not be restored and he took control of the airplane. He indicated that he activated the fuel boost pump, but he does not recall what the fuel pressure was beforehand. The airplane was examined at the accident site by the FAA on October 12, 1994; the airplane was examined by the NTSB at Republic Airport on October 18, 1995. The FAA examination determined the fuel boost pump switch was in the "on" position. The engine examination confirmed drive train continuity, magneto sparking, spark plug operation, fuel in the lines to the fuel manifold distributor valve, cylinder compression, and attachment of powerplant controls between the throttle quadrant to the applicable engine mounted accessories. Also, a visual check was negative for the presence of water contamination. Evidence of mechanical malfunction was not disclosed during the examination. According to the FAA approved Airplane Flight Manual (AFM) for the Beech A-36 airplane the following, in part, is stated for the auxiliary fuel pump: The electric auxiliary fuel pump is controlled by the ON- OFF toggle switch on the control console and provides pressure for starting and emergency operation. Immediately after starting, the auxiliary fuel pump can be used to purge the system of vapor caused by an extremely high ambient temperature or a start with the engine hot. The auxiliary fuel pump provides for near maximum engine fuel requirements, should the engine driven pump fail. According to the AFM, the airplane is to be placarded to state in part: AUX FUEL PUMP OPERATION Take-Off and Land With Aux Fuel Pump Off Except In Case Of Loss of Fuel Press The emergency procedures stated in the AFM for loss of engine power states, in part, the following: 1. Fuel Flow Gage - Check If fuel flow is abnormally low: a. Mixture - Full Rich b. Auxiliary Fuel Pump - On (then Off if performance does not improve in a few moments)