Pilot Debrief

CESSNA 182J near Weatherford, TX — 2016-07-19

Final reportCEN16LA270
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Date
2016-07-19
Location
Weatherford, TX, USA
Airport
WEA
Aircraft
CESSNA 182J
Registration
N2644F
Category
Airplane
Highest injury
Serious
Fatalities
0
Phase of flight
Initial climb

Probable cause

An electrical system malfunction for reasons that could not be determined, and the subsequent loss of engine power due to the loss of the electrical boost pumps. Also causal was the pilot's improper emergency action following the loss of engine power due to his lack of knowledge regarding the engine’s supercharger system.

NTSB narrative

The private pilot stated that, shortly after takeoff and while 300 to 500 ft above ground level, the engine experienced a loss of power when he activated the flap switch. The pilot troubleshot the loss of power and attempted to restart the engine; the engine restarted momentarily, then lost power again. The pilot did not pull the boost cutoff control. During the emergency landing, the airplane collided with a barbed wire fence and impacted several trees. An electronic engine monitor provided data from the accident flight. There were several noticeable voids in the engine monitor data, indicative of electrical power interruptions to the device. The final electrical power interruption occurred about the time of the accident. The investigation was unable to determine a reason for the electrical power interruptions to the engine monitor other than the cycling of the avionics switch. The airplane's electrical system could not be functionally tested due to impact damage. Four engine test runs were conducted, revealing no anomalies. During the tests, the battery voltage displayed 13 to 15 volts, and the ammeter did not show a discharge. Examination of the airplane revealed that the aftermarket supercharger drive belt was improperly installed upside down. The fuel inlet screen contained a small amount of multicolor organic material similar to tree leaves. The presence of organic material did not adversely affect the engine test runs, and likely was the result of the impact with trees during the accident sequence. According to the emergency procedures provided by the supercharger manufacturer, the supercharged engine can be operated during a loss of electrical power by pulling the boost cutoff control. Pulling the boost cutoff control results in gravity-fed fuel supplying the engine at un-boosted manifold pressure and allows operation as a normally-aspirated engine. Further, if the boost cutoff control is not pulled when electrical power is lost, surging occurs as the carburetor bowl empties and refills and will continue as long as fuel is available in the fuel system. The surging stops when the boost cutoff control is pulled. It is likely that, had the pilot pulled the boost cutoff control, the engine would have stopped surging and engine power would have been restored. The pilot stated he was not trained in the operation of the supercharger; however, the airplane flight manual supplement contained information regarding supercharger operation and emergency procedures.

Analysis

Primary failure mode
Engine power loss
First missed decision gate
Pilot could have pulled the boost cutoff control to attempt engine recovery.

NTSB coding

Evidence available

  • Photos
  • 15 docket documents
View NTSB final reportView NTSB docket

Docket documents15

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