Flight History
On July 13, 2017, about 1245 Pacific daylight time, a Cirrus Design Corporation SR22T airplane (registration N821SG) was destroyed when it impacted terrain in Schellville, California, about half a mile west of Sonoma Skypark Airport (0Q9), Sonoma, California. The private pilot and a passenger were fatally injured, one passenger was seriously injured, and one passenger received minor injuries. The airplane was operated by the pilot as a personal flight under Title 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed, and no flight plan had been filed. The flight originated from 0Q9 and was destined for Reid-Hillview Airport in San Jose, California.
According to data from the airplane's recoverable data module, at 1244:10 engine power was increased for takeoff. At the start of the takeoff roll, engine power was about 113%, manifold pressure about 37.5 inches of mercury (inHg), fuel flow about 43.5 gallons per hour (gph), and engine speed just above 2,500 rpm. At rotation (1244:30), indicated airspeed was about 73 knots. The airplane accelerated and climbed for the next 5 seconds at about 87 knots. During climb at about 15° nose-up pitch, manifold pressure was 36.5 inHg, fuel flow between 43.2 and 43.8 gph, and engine speed at or above 2,500 rpm.
At 1244:40, engine speed peaked at 2,563 rpm, manifold pressure at 37.8 inHg. Two seconds later, fuel flow peaked at 46.6 gph, then engine speed decreased to 2,402 rpm the next second. At 1244:44, engine speed and fuel flow began decreasing, airspeed decreased from 86 knots, and the airplane leveled off at about 209 ft mean sea level (msl). Pitch decreased then increased, airspeed continued decreasing. At 1244:45, engine speed was 1,788 rpm, fuel flow 40.5 gph, airspeed 81 knots. Three seconds later at 72 knots, the airplane reached peak altitude of 227 ft msl, then began descending. At 1244:49, the stall warning system activated. One second later, engine speed was 1,212 rpm, altitude 185 ft msl, airspeed 71 knots, vertical speed -608 ft/min. At 1244:51, stall warning activated again; altitude 157 ft msl, engine 1,236 rpm, airspeed 76 knots, vertical speed -768 ft/min.
The airplane was equipped with a Cirrus Aircraft Parachute System (CAPS). At 1244:52, the system handle was pulled; at that time, the airplane was banked about 27° left, altitude about 130 ft msl, airspeed 75 knots. Last recorded data at 1244:53 showed altitude about 90 ft msl, airspeed 75 knots, pitch about 16° nose down, bank about 68° left, engine speed 1,174 rpm, fuel flow 30.4 gph.
Several witnesses at or near 0Q9 reported hearing the engine "sputter" or "pop" a few times as the airplane passed. Subsequently, a louder sound was heard, and shortly thereafter the parachute system deployed. Most witnesses saw the airplane descending before losing sight at treetop level, just before impact.
Pilot and Aircraft Information
The pilot held a private pilot certificate with ratings for airplane single-engine land and instrument airplane. He was issued a third-class medical certificate on July 11, 2017, with no limitations. According to his application, he had accumulated 550 total flight hours, with 30 in the previous 6 months. A logbook review indicated about 604 total hours, with about 390 hours in the Cirrus SR22, most in the accident airplane since August 1, 2011. In the previous 7 months, the pilot flew the accident airplane on nine flights totaling about 19.8 hours.
The low-wing, fixed-gear airplane was manufactured in 2011. It was powered by a 315-horsepower Continental Motors TSIO-550-series reciprocating engine with a three-bladed, constant-speed composite propeller. The most recent conditional inspection was completed on November 10, 2016, at an airframe total time of about 349 hours.
The Pilot's Operating Handbook (POH) specified the engine speed upper warning range as greater than 2,550 rpm, manifold pressure upper warning range between 37.5 and 40.0 inHg, and normal fuel flow range between 10 and 45 gph. The POH stated that for maximum power operations, fuel flow should be in the green arc. It also included takeoff power check instructions and stall speeds. At maximum gross weight (3,400 pounds) and no bank, stall speed was 73 knots at forward CG and 72 knots at aft CG. At 30° bank, stall speed was 76 knots. The POH warned about uncoordinated control inputs near stalls, especially close to the ground, and noted altitude loss during a wings-level stall may be 250 ft or more. The emergency checklist for engine failure during takeoff at low altitude recommended aborting on the runway if possible, or lowering the nose to maintain airspeed and gliding straight ahead. Best glide speed was 88 knots. The POH stated no minimum altitude for CAPS deployment but advised activation at or above 2,000 ft if circumstances permit; at any altitude, deploy without delay if it is the only alternative.
The airplane's fuel system included an engine-driven fuel pump and an electrically powered auxiliary fuel pump controlled by a three-position rocker switch: Boost (forward) for takeoff, climb, landing, and tank switching; Off (center); and High Boost/Prime (aft) for priming and suppressing vapor above 18,000 ft. The Boost position delivers 4-6 psi; High Boost/Prime delivers up to 16 psi and 42 gph, with a lockout relay allowing operation when manifold pressure >24 inHg or engine speed <500 rpm. The maintenance manual recommended fuel flow at 36.5 inHg of 37.4-40.5 gph.
Weather and Airport
Weather recorded at Petaluma Municipal Airport, about 8 miles west, at 1255: wind variable at 6 knots, visibility 9 statute miles, sky clear, temperature 25°C, dew point 13°C, altimeter 30.00 inHg. Sonoma Skypark Airport (0Q9) is privately owned, non-towered, elevation 20 ft msl, with an asphalt runway 08/26, 2,480 ft long and 40 ft wide.
Wreckage and Engine Examination
The airplane impacted a wheat field and came to rest upright on a heading of about 006°. The right wing remained attached; the left wing separated. The empennage separated aft of the avionics bay. The engine came to rest inverted, about 45° from the fuselage heading, with all mounts separated. The three-bladed propeller remained attached; two blades separated at the hub. Postaccident examination revealed the crankshaft could be rotated manually, with continuity throughout the engine. Thumb compression and suction were attained on all cylinders; borescope inspection showed normal operational conditions. Fuel in the line between the metering unit and manifold valve tested negative for water contamination. The fuel manifold and nozzles showed no anomalies. The engine-driven fuel pump was impact-damaged; examination showed fuel pouring from fittings, the shear drive coupler intact, drive shaft rotating freely, vanes intact, no contamination. The electric fuel pump control switch was substantially damaged, precluding determination of its position. Ignition system examination: top sparkplugs with dark insulators (consistent with rich mixture); both magnetos produced spark at distribution towers; ignition key in "both" position; no anomalies in switch or wiring. No preimpact mechanical malfunctions or failures were found.
Additional Information
Toxicology testing identified fexofenadine (a non-sedating antihistamine acceptable for flying) in the pilot's blood and urine, and azacyclonol (a metabolite) in urine only; negative for carbon monoxide and ethanol. The autopsy listed multiple blunt force injuries as cause of death.
Data from the recoverable data module and seven previous flights showed that during three previous flights, fuel flow exceeded 41.0 gph and manifold pressure exceeded 36.5 inHg during takeoff. Peak fuel flow and manifold pressure in those flights ranged up to 43.9 gph and 37.5 inHg, compared to 46.6 gph and 37.8 inHg in the accident flight. Before engine start for the accident flight, fuel flow was 21.4 gph, consistent with activation of the High Boost/Prime switch. Before takeoff, fuel flow was 3.5 gph at 1,078 rpm.
The report also referenced a related accident on September 7, 2018, in Kennett, Missouri, where a Cirrus SR22T experienced a complete loss of engine power after takeoff when the pilot inadvertently placed the fuel pump in High Boost/Prime. That accident's data showed a fuel flow increase of about 2.55 gph to between 41.0 and 42.9 gph after the switch activation.
On May 7, 2018, Cirrus issued Service Advisory SA 18-02 reminding pilots that the fuel pump should be set to Boost—not High Boost/Prime—for takeoff, climb, landing, and tank switching, and that fuel flow should never exceed 41 gph and 36.5 inHg manifold pressure, as higher flow may cause rough engine operation or power loss.