The pilot reported that for takeoff, both fuel selectors were ON, and his initial climb was conducted at 90 to 100 knots, with a 10 to 15 degree pitch attitude. He momentarily leveled at 2,200 feet, and sensed a decrease in engine torque. The low fuel pressure light illuminated, and the fuel flow was lower than normal. The pilot turned the boost pump and ignition ON, and there was no change in engine condition or fuel flow, and the low fuel pressure light remained illuminated. He then advanced the power lever to the full power position, and there was no response from the engine. The pilot heard what he thought was an engine noise, which he described as a decreasing sound. He set up for a forced landing in a field. The airplane came to rest near a residence, inverted. PROBABLE CAUSE: “The pilot’s failure to verify the position of the fuel selectors prior to takeoff, which resulted in a power loss due to fuel starvation. A factor was the failure of the fuel selector warning horn.”