CIRRUS DESIGN CORP SR22 — Hutchinson, MN

What happened

During a familiarization flight, the pilot configured the airplane at an airspeed of 80 knots, with full flaps extended, in preparation for a touch-and-go landing. The mixture was set to full rich and the fuel boost pump was set on “Low Boost.” According to the flight instructor, the approach altitude was slightly high, so he instructed the pilot to perform a forward slip. The pilot decreased the engine power to idle and performed the forward slip as instructed. The flight instructor reported that, as they crossed the runway threshold, the pilot allowed the airspeed to get too slow and he did not stop the descent rate, which resulted in a “noticeable bounce” on the main landing gear.

The flight instructor told the pilot to initiate a go-around and the pilot added power, reduced the flaps to 50%, and established a normal climb attitude. The flight instructor reported that the airplane began to climb very slowly. He stated the airspeed increased to 80 knots, at which time he instructed the pilot to raise the flaps. The flight instructor confirmed the airplane’s flaps were up, but the airplane continued to climb about 300 ft per minute. He stated that he expected an increase in airspeed but was surprised that the airspeed was slightly above 85 knots. In addition, he felt a “shudder of an irregular vibrational tick.” He stated it was a noticeable “clunky” sound that resonated through the fuselage every few seconds. The airplane continued to climb at a slower-than-normal rate.

Upon reaching 500 ft above ground level the flight instructor stated, “CAPS [Cirrus Airframe Parachute System] available.” At this time, the pilot turned over control of the airplane to the flight instructor. The airplane’s performance continued to decrease so the flight instructor aligned the airplane for an open field and the pilot deployed the airplane parachute system. The flight instructor secured the airplane before it impacted an open snow-covered field.

The airplane sustained substantial damage to the forward fuselage, both wings, and the rudder. The fuel selector valve shaft was fractured between the valve handle and the valve shaft housing and the valve was positioned between the right fuel tank and the off position. The fuel selector valve was moved by first responders after the accident from the right fuel tank to the off position. Investigators were unable to determine if the fractured valve shaft was a result of the accident or due to movement of the handle by first responders after the accident. Testing performed by the manufacturer indicated that engine performance and fuel flow would not be impacted with the fuel selector valve handle between the two tanks and partially open.

The engine fuel lines were secure. The fuel servo and boost pump fuel inlet lines were absent of fuel and a small amount of fuel was present in both the left and right wing header tanks. The left fuel tank was compromised and fuel staining was observed directly beneath the wing. There was no visible fuel in the right wing fuel tank. Investigators were unable to determine how much fuel was on board at the time of the accident because of the compromised fuel tank.

Recorded parameters from the onboard data module were consistent with the training flight described by the flight instructor. About 1254 the recorded parameters were consistent with the go-around initiated by the pilot with an increase in engine rpm, fuel flow, and manifold pressure. However, the increase in fuel flow was not equivalent to the increase seen during the initial takeoff and at several points earlier in the flight. At that time the exhaust gas temperature and cylinder head temperatures for cylinder Nos. 2, 4, and 6 diverged; cylinder No. 2 increased in temperature and cylinder No. 6 decreased in temperature.

Two postaccident engine runs confirmed the function of the engine but were limited in duration due to impact damage. An examination of the engine, airframe, and related systems revealed no mechanical anomalies that would have precluded normal operations. The recorded engine parameters and the description from the flight instructor are consistent with a loss of engine power, likely due to a reduced fuel flow; however, investigators were unable to determine the reason for the reduced fuel flow and subsequent loss of engine power.

The pilot’s postmortem toxicology testing indicated that he had used the antidepressant medication citalopram. It is unlikely that effects of this medication or an associated underlying condition contributed to the crash; the pilot’s actions as reported by the surviving instructor appeared appropriate to the situation.

An editorial "what led to it / how to avoid it" analysis for this accident is generated separately and will appear here.