History of Flight
On January 4, 2014, about 1735 eastern standard time, a Cirrus SR22, registration N450TX, was substantially damaged after the pilot deployed the Cirrus Airplane Parachute System (CAPS) and the aircraft impacted a motor vehicle and then terrain in Buckhannon, West Virginia. The private pilot received minor injuries, and the driver of the motor vehicle was not injured. The flight departed Donegal Springs Airpark (N71) in Marietta, Pennsylvania, about 1405, destined for Upshur County Regional Airport (W22) in Buckhannon, West Virginia. Visual meteorological conditions prevailed, and no flight plan was filed for the personal flight conducted under 14 CFR Part 91.
According to the pilot, he departed N71 around 1405. About 10 miles from W22, he called on UNICOM and verified weather conditions. Advised that no aircraft was in the traffic pattern, he opted for a straight-in approach to runway 29. About 5 miles from touchdown, at an approach speed of approximately 100 knots indicated airspeed, he performed his prelanding checklist. Both fuel tanks contained about 25 gallons each; he verified the fuel selector was on the fullest tank, turned on the fuel boost pump, lowered wing flaps to 50%, and set the mixture to about 60%. He made a final approach call around 4 miles from touchdown and again verified airport conditions on UNICOM.
Approximately 3 miles from the threshold of runway 29, at 400 to 500 feet above ground level, he increased throttle to compensate for normal airspeed loss on final approach. To his surprise, nothing happened. He expected a pitch change, vibration change, and airspeed stabilization, but none occurred. He moved his hand to manipulate both throttle and mixture simultaneously and increased both to maximum. Again, no response in engine noise, vibration, or gain in airspeed. The indicated airspeed decayed below 80 knots. Knowing he was at or below the published minimums for CAPS, he deployed it by pulling the red "T" handle with his right hand while maintaining control with his left. He transmitted a "Mayday" call over the radio. After CAPS deployment, he tightened his restraint before impact, then shut down the airplane's systems and exited.
Personnel Information
The pilot held a private pilot certificate with ratings for airplane single-engine land and instrument airplane. His most recent FAA third-class medical certificate was issued on May 5, 2012. He reported 544 hours of total flight experience, of which 501 were in the accident airplane make and model.
Aircraft Information
The airplane was manufactured in 2004 and certificated in the NORMAL category. Its most recent annual inspection was completed on February 20, 2013. At the time of the accident, the airplane had accrued 979 total hours of operation.
Meteorological Information
The recorded weather at W22 at 1735 included winds calm, visibility 10 miles, clear sky, temperature 04°C, dew point -15°C, and altimeter setting 30.10 inches of mercury.
Wreckage and Impact Information
Examination of the accident site revealed that after CAPS deployment, the airplane first struck a pickup truck traveling on a roadway, then terrain, with the parachute canopy coming to rest on top of three vehicles at an automobile dealership. Fuel was present on the roadway surface. The airplane sustained substantial damage. Impact damage was visible on the left wing leading edge ahead of the pitot tube mounting location, exposing composite skin. A portion of the pitot tube had separated. The left wing lower skin exhibited impact damage above the left main landing gear, which had penetrated the bottom of the left wing and left main fuel tank. The nose landing gear had separated, and two blades of the four-bladed propeller were bent back. Both wing flaps remained attached; the right flap was bent back on the outboard portion, and the left flap displayed impact damage. The fuselage showed damage from CAPS deployment with peeling of a composite strip layer on both sides, as designed.
Further examination revealed the wing flaps were in the 100% (full extension) position, the ignition switch was in the BOTH position, the fuel pump was on BOOST, the power lever was in the MAX position, and the mixture control was found approximately 2 inches forward of the idle CUTOFF position.
Flight Recorder Data
The accident airplane was equipped with a Primary Flight Display (PFD) and Multi-Function Display (MFD) that recorded data. The PFD recorded 25 power cycles; the accident flight was the 22nd, with a duration of about 2 hours and 38 minutes. The MFD compact flash card contained 105 data files, one for the accident flight, also approximately 2 hours and 38 minutes in duration.
Data from 14:56 to 17:41 showed a normal takeoff and climb, followed by a slower-than-normal cruise at low power (around 2,000 rpm) from 15:24 to 15:59. Around 15:59, the airplane performed a series of eight high-performance 360-degree turns with bank angles up to 80° and peak vertical acceleration of 3.3 Gs. Two aileron rolls to the left occurred at 16:47 and 16:51, with vertical acceleration between +2.5 and -0.5 Gs. After the rolls, the flight continued with low rpm (about 2,000) and airspeed around 100 knots at altitudes between 6,000 and 7,000 feet. The airplane began descending around 17:30; rpm decreased below 2,000 for the remainder of the flight. CAPS deployed at 17:34:33 at a pressure altitude of 1,928 feet (about 637 feet AGL). At deployment, indicated airspeed was 82 knots, and the airplane was in a generally wings-level attitude about 0.76 nautical miles from the runway 29 threshold.
Review of engine parameters showed nominal responses during cruise. A rapid drop in oil pressure (32 psi) occurred during the negative G portion of the second aileron roll. During descent, manifold pressure and fuel flow decreased, and two distinct drops in exhaust gas temperature (EGT) were noted just prior to CAPS activation.
Tests and Research
Engine examination revealed no external damage. The top and bottom spark plugs showed no anomalies, and borescope inspection of cylinder combustion chambers revealed no discrepancies. The crankshaft rotated with continuity to the accessory section, spark was noted on all six top spark plug leads, and thumb compression was obtained on all six cylinders.
The damaged propeller was replaced with a two-bladed test propeller, and the engine was run using an external fuel tank. The engine started and warmed up normally. The throttle was advanced and retarded multiple times with no hesitation. Full throttle produced 2,400 rpm, and a magneto check showed minimal drop. The engine was set at approximately 1,800 rpm, and the mixture lever was moved to a position similar to the as-found position (approximately 2 inches forward of idle cutoff). When the throttle was advanced, the engine stumbled and would not respond with an increase in rpm.
According to the Cirrus SR22 Pilot's Operating Handbook (POH), the mixture control should be set "AS REQUIRED" for descent and landing, and the minimum cruise rpm is 2,500. The on-board Quick Reference Checklist specifies mixture "AS REQUIRED" during descent and "FULL RICH" before landing. The Continental IO-550 engine manual states minimum cruise rpm is 2,300 and requires the mixture to be adjusted for smooth operation during descent and placed in "FULL RICH" for landing. Teledyne Continental Service Bulletin CSB09-11 warns that sustained cruise rpm below 2,300 can lead to crankshaft counterweight release and engine stoppage.