Accident Summary
On October 24, 2020, at approximately 1200 central daylight time, a Cirrus SR22, registration N183V, was substantially damaged when it impacted terrain near Tishomingo, Oklahoma. The pilot and three passengers sustained minor injuries. The flight was conducted as a personal flight under Title 14 Code of Federal Regulations Part 91.
Flight and Pilot Actions
While descending toward its destination, Atoka Municipal Airport in Atoka, Oklahoma, the pilot received a high oil temperature warning and noted a loss of engine power. He attempted to restore power by adjusting the mixture and throttle but was unsuccessful. Data from the airplane’s remote data module indicated erratic high oil temperatures, ranging from 314°C to 801°C, for 5 seconds. The oil temperature then returned to normal for 7 seconds before again becoming erratic for the remainder of the flight. According to the pilot’s operating handbook, oil temperatures exceeding 240°C triggered a flashing red cockpit annunciator and an aural chime every 1.5 seconds.
Approximately 5 seconds after the high temperatures began, the data showed decreases in fuel flow, manifold pressure, and engine rpm, consistent with throttle movement to idle. About 3 seconds later, manifold pressure increased (consistent with throttle increase), but fuel flow remained near 3 to 5 gallons per hour. Subsequent manifold pressure fluctuations were not accompanied by corresponding fuel flow changes.
Assessing his options, the pilot determined that no suitable forced landing sites were available. He then activated the Cirrus Airframe Parachute System (CAPS). The data showed parachute deployment occurred about 45 seconds after the high oil temperatures began, at an airspeed of approximately 85 knots. The airplane descended under parachute and impacted terrain, resulting in substantial damage to the engine mount.
Engine and System Examination
Postaccident examination of the engine revealed normal mechanical continuity. The fuel inlet filters were clear of debris, and no anomalies were noted with ignition leads, spark plugs, magnetos, fuel servo, flow divider, or fuel injectors. The oil reservoir was empty, and several holes were found in the oil pan due to impact damage. The oil temperature connector and back shell were damaged, and the back shell was disconnected from the connector.
Maintenance Context
The accident flight was the first flight after maintenance performed to address high engine oil consumption during previous flights. The maintenance record included replacement of crush gaskets on the oil cooler housing. One of the replaced crush gaskets was located adjacent to the damaged oil temperature connector.
Additional Information
According to a Federal Aviation Administration Safety Team (FAAST) publication, general aviation accidents often result from inappropriate responses to unexpected events. The publication noted that humans are subject to a “startle response” when faced with unexpected emergencies, which may delay action or lead to inappropriate responses. It stated that training and preparation can reduce startle response time and promote more effective and timely responses.