N2644F

HISTORY OF FLIGHTOn July 19, 2016, at 0903 central daylight time, a Cessna 182J airplane, N2644F, experienced a loss of engine power after departure and the pilot conducted a forced landing to a field near Weatherford, Texas. The private pilot and one passenger sustained minor injuries and the second passenger sustained serious injuries. The airplane sustained substantial damage. The airplane was registered to and operated by the pilot under the provisions of 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed for the flight which was operated without a flight plan. The flight was departing from Parker County Airport (WEA), Weatherford, TX, and was en route to Pecos Municipal Airport (PEQ), Pecos, Texas.

The pilot reported that he had departed from Denton Enterprise Airport (DTO), Denton, Texas, which was about 36 miles northeast of WEA. He landed at WEA and two passengers boarded the airplane while the engine continued to operate. He then taxied to the runway and noted that all the instruments showed normal operations, including the JPI engine data monitor (EDM) 700. He extended the flaps 10° for takeoff, increased the engine power to 29 inches of engine manifold pressure and 2,600 rpm, and lifted off at 60 to 65 mph. After takeoff, he retracted the flaps and noticed that the avionics turned off. He cycled the avionics master switch, but the avionics did not turn on again. About 40 seconds after takeoff while 300 to 500 ft above ground level, the engine experienced a loss of power. He attempted to troubleshoot the loss of power and to restart the engine; the engine restarted for about two seconds and then lost power again. The pilot did not remember if the engine ever experienced a total loss of power since he was concentrating on flying the airplane. He also did not remember if he ever pulled the boost cutoff control. He did not continue to troubleshoot the issue since his altitude was low and made a shallow bank towards a field for an emergency landing. During the landing, the airplane collided with a barbed wire fence, continued into a field, impacted several trees and came to rest on a road (figure 3). When the airplane came to rest, the pilot noted that fuel was pouring out of the fuel tanks all over the occupants. The pilot and two passengers exited the airplane.

A witness, who was working in a field north of the accident site, stated that he heard an airplane engine overhead. He observed the accident airplane in a descent, apparently attempting to land in a pasture when it hit a fence in the middle of the pasture (figure 1). He called 911 and drove to the accident site. He observed three occupants who were already out of the airplane and noticed that fuel was pouring out of the wings onto the ground.

The pilot stated to a Federal Aviation Administration (FAA) inspector, that one of the passengers recalled hearing the engine regain power just before touching down in the field.

Figure 1 – Google Earth view of GPS track AIRCRAFT INFORMATIONA Forced Aeromotive Technologies (FAT) supercharger was installed on the airplane in May 2004 under supplemental type certificate (STC) SE10233SC and STC SA10232SC.

On June 20, 2016, an annual inspection was completed at a tachometer time of 2,245.3 hours. During the inspection the maintenance personnel "checked and adjusted supercharger belt as per Force Air Tech service instructions."

The pilot stated he was not trained of the operation of the supercharger by the manufacturer or the previous airplane owner after he purchased the airplane, nor was he required to do so. AIRPORT INFORMATIONA Forced Aeromotive Technologies (FAT) supercharger was installed on the airplane in May 2004 under supplemental type certificate (STC) SE10233SC and STC SA10232SC.

On June 20, 2016, an annual inspection was completed at a tachometer time of 2,245.3 hours. During the inspection the maintenance personnel "checked and adjusted supercharger belt as per Force Air Tech service instructions."

The pilot stated he was not trained of the operation of the supercharger by the manufacturer or the previous airplane owner after he purchased the airplane, nor was he required to do so. WRECKAGE AND IMPACT INFORMATIONThe responding FAA inspector reported that the left wing was folded over the top of the fuselage and the right wing was bent aft. The top of the cabin area had been opened and displaced aft. The fuselage was bent upward near the front seats (figure 2).

Figure 2 – Accident airplane

A postaccident examination of the airframe and engine was conducted by the NTSB Investigator-in-Charge (IIC), with technical representatives from Textron Aviation and Continental Motors, after recovery from the accident site. The engine was intact with no noticeable external damage. It was equipped with a FAT belt driven supercharger system that included two fuel boost pumps between the airframe fuel line and the engine carburetor. The top spark plugs and cylinder rocker covers were removed and the crankshaft was manually rotated with continuity confirmed to all cylinders and to the rear of the engine. The chromed cylinders were examined using a lighted borescope; all cylinder domes and pistons exhibited normal combustion deposits. All intake and exhaust valves were in place and free to move; suction and compression was confirmed in each cylinder. The magneto timing was checked and both magnetos were found to be timed at 22

°

before top dead center, which was normal timing. The top spark plugs exhibited normal wear signatures and dark deposits in the electrode areas. The air intake filter was clean and clear. The oil filter was in place and not damaged. The filter was opened and contained no debris or metal deposits in the filter element.

The propeller remained attached to the crankshaft. Both propeller blades were bent and twisted aft and exhibited chordwise scratches and polishing. The cowl flap lever was positioned to OPEN. The carburetor heat control knob was full forward. The boost cutoff control knob was full forward and was not labeled on the instrument panel. The rudder and elevator flight control cables were continuous and undamaged. The left and right wings had been removed during the recovery process. The aileron flight control cables exhibited multiple overload separations. One portion of the left aileron control cable had been cut during the recovery process.

The flap motor was energized with an external battery and operated the flaps normally. The flaps were found extended 10°. Due to impact damage and the displacement of the airplane during recovery the entire electrical system could not be functionally tested.

An engine test run was conducted by the NTSB IIC and technical representatives from Textron Aviation, Continental Motors, and FAT. Prior to the test run procedures, the engine was examined. The gascolator screen was removed and was clean and clear of contaminants. The fuel inlet screen was removed from the carburetor and contained a small amount of multicolor organic material similar to tree leaves. The airplane had been stored outdoors at the storage facility.

An external fuel source was connected to the airframe fuel line and the engine was started and test run several times. The engine operated at full power performance according to the STC operating specifications. The alternator inoperative and low fuel pressure lights were pressed and illuminated as expected. The lights did not illuminate during the engine test runs. The ammeter remained near zero and did not show a discharge.

After the test runs were completed the carburetor was removed and examined. The carburetor was in place and not damaged. The throttle and mixture controls remained connected appropriately and were free to move. The unit was disassembled and the bowl was clean and clear. The floats and needle valve were attached and were free to move. The needle valve seat was clean and clear.

Also following the test runs, the engine cowling was opened to facilitate further examination of the engine compartment. The supercharger drive belt was installed on the idler gear inside out. ADDITIONAL INFORMATIONFAT Supercharger Information

The Airplane Flight Manual Supplement (AFMS) states that the supercharger supplies boosted engine induction air (figure 3) so it is necessary to boost fuel pressure to ensure an unimpeded flow of fuel through the carburetor. The two fuel pumps supply fuel to the carburetor at the required pressure. Either pump will independently supply sufficient fuel pressure for engine operation, but two are installed to provide backup in case of a pump failure. According to the STC manufacturer, as the fuel level in the carburetor changes, air flows in and out of the fuel bowl through a passage inside the mouth of the carburetor. When the supercharger is installed, this air passage becomes pressurized and at power levels above 1,700 rpm, the pressurized air in the fuel bowl pushes the fuel out and back to the fuel tank. The electric fuel boost pumps counter the air pressure so that the fuel enters the float chamber correctly.

Figure 3 – FAT Supercharger Diagram

The AFMS further states that in the event of a complete electrical failure (alternator or battery), the engine can be operated using gravity-fed fuel at un-boosted manifold pressure using the boost cutoff control. When the boost cutoff control is pulled, pressurized air from the supercharger is dumped into the engine compartment before reaching the carburetor. This lowers the carburetor's requirement for pressurized fuel and allows operation as a normally-aspirated engine. The STC owner added that, during a complete electrical system failure, the effect would be the same as turning off the fuel boost pumps. With the fuel boost pumps off and engine power above 1,700 rpm, the carburetor fuel bowl would empty in 5 to 10 seconds. With the fuel bowl empty, the eng...