Buckhannon, WV, USA
N450TX
CIRRUS DESIGN CORP SR22
The private pilot was conducting a personal cross-country flight. Although recorded data from the airplane's flight displays indicated that, during the cruise portion of the flight, the airplane conducted several aerobatic maneuvers for which it was not certificated and which exceeded its published limitations, the data also showed that the engine operated normally during the maneuvers; therefore, they did not contribute to the loss of engine power. According to the pilot, when the airplane was about 5 miles from touchdown and at approach speed, he performed his "prelanding" checklist, which he later stated he knew "by heart"; verifying that the fuel boost pump was on; lowering the wing flaps to 50 percent; and setting the fuel mixture to about 60 percent. About 3 miles from the runway threshold, between about 400 and 500 ft above ground level, the pilot increased the throttle to compensate for the normal airspeed loss on final approach; however, the engine did not respond. He reported that he then "moved his hand in a manner to manipulate both throttle and mixture at the same time" and increased both to maximum, but the engine still did not respond. The pilot determined that the airplane was at, or just below, the published minimums for deploying the ballistic parachute system, and he deployed it. After the parachute was deployed, the airplane struck terrain and a motor vehicle. During examination of the airplane, the flaps were found fully extended, which was the correct configuration for landing. The throttle was found in the "max" position; however, the mixture control was found in a position about 2 inches forward of the idle "cutoff" position, which was consistent with a cruise setting and indicated that it was not in the "maximum" position as reported by the pilot. Recorded data showed that, during the descent, both a reduction in the manifold pressure and fuel flow occurred and that, subsequently, a distinct reduction in exhaust gas temperature for all six cylinders occurred, corroborating that the mixture control was not advanced to maximum for the descent and landing. This information would have been available to the pilot on the airplane's display system and would have provided him sufficient information to note that his improper positioning of the mixture control was causing the loss of engine power. During the postaccident engine test run, the throttle was advanced and retarded multiple times with no hesitation or stumbling noted. A magneto check was also performed with minimal drop on either magneto. The engine was then set to about 1,800 rpm to simulate an approach to landing and the mixture control was moved to its as-found position. When the throttle was advanced, the engine stumbled and would not respond when the rpm was increased. Given this evidence, it is likely that the pilot's failure to move the mixture lever to the "full rich" position during the approach to landing led to the reduction in engine power. According to airplane manufacturer, engine manufacturer, and Federal Aviation Administration guidance, during descent, the mixture was required to be adjusted for smooth engine operation, and before landing, the mixture control was required to be placed in the "full rich" position. As noted, the mixture control was not found in the "full rich" position. Postaccident examination and interviews revealed that the airplane's quick reference handbook and the Pilot's Operating Handbook were not available for the pilot to reference during the flight. Further, although an electronic set of checklists was available for use on the airplane's multifunction display, the pilot did not indicate that he had used them. If the pilot had referenced the landing checklist (on paper or on the multifunction display) or manuals, he might have recognized the reason the engine was nonresponsive and moved the fuel control mixture to the proper position for landing and prevented the loss of engine power.
HISTORY OF FLIGHTOn January 4, 2014 about 1735 eastern standard time, a Cirrus SR22, N450TX, was substantially damaged after the pilot deployed the Cirrus Airplane Parachute System (CAPS) and impacted a motor vehicle and then terrain in Buckhannon, West Virginia. The private pilot received minor injuries. The driver of the motor vehicle was not injured. The flight departed from Donegal Springs Airpark (N71) Marietta, Pennsylvania, about 1405, destined for Upshur County Regional Airport (W22), Buckhannon, West Virginia. Visual meteorological conditions prevailed, and no flight plan was filed for the personal flight, conducted under the provisions of Title 14 Code of Federal Regulations (CFR) Part 91. According to the pilot, he departed N71, around 1405. About 10 miles from W22, the pilot called in on the UNICOM frequency, and verified the weather conditions. He was advised that there was no aircraft in the traffic pattern, so he opted for a straight in approach to runway 29. About 5 miles from touchdown, he was at an approach speed of approximately 100 knots indicated airspeed. He performed his prelanding checklist. Both fuel tanks had approximately 25 gallons of fuel in them and he verified that the fuel selector was on fullest tank. He verified that the fuel boost pump was on, lowered the wing flaps to 50 percent, and set the mixture to about 60 percent. He then made a final approach call around 4 miles from touchdown, and verified the airport conditions on UNICOM once again. Approximately 3 miles from the threshold of runway 29, at 400 to 500 feet above ground level, he increased throttle to compensate for the normal airspeed loss on final approach. To his surprise, nothing happened. He was expecting to hear a pitch change, feel a subtle change in vibration, and see his airspeed stabilize but, none of those events occurred. He "moved his hand in a manner to manipulate both throttle and mixture at the same time" and increased both to maximum. Again, no response in engine noise, vibration, or gain in airspeed occurred. The indicated airspeed had now decayed to below 80 knots. Knowing that he was just at, or just below, the published minimums for the Cirrus Airframe Parachute System (CAPS), he deployed it by pulling the red "T" handle with his right hand while maintaining control of the airplane with his left hand. He then transmitted a "Mayday" call over the radio. After the CAPS deployed, he tightened his restraint prior to impact. After impact he shut down the airplane's systems, and exited the airplane. PERSONNEL INFORMATIONAccording to Federal Aviation Administration and pilot records, 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 INFORMATIONAccording to FAA and airplane maintenance records, the airplane was manufactured in 2004 and was certificated in the "NORMAL" category. The airplane's 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 INFORMATIONThe recorded weather at W22 at 1735, included: winds calm, 10 miles visibility, clear, temperature 04 degrees C, dew point -15 degrees C, and an altimeter setting of 30.10 inches of mercury. AIRPORT INFORMATIONAccording to FAA and airplane maintenance records, the airplane was manufactured in 2004 and was certificated in the "NORMAL" category. The airplane's 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. WRECKAGE AND IMPACT INFORMATIONAccident Site Examination of the accident site revealed that after the CAPS deployment, the airplane first struck a pickup truck that was traveling on a roadway, then terrain, with the canopy of the parachute coming to rest on top of three vehicles at an automobile dealership. Fuel from the airplane was observed to be present on the surface of the roadway. Airplane Examination Examination of the airplane revealed that it had sustained substantial damage during the impact sequence after the CAPS deployment prior to coming to rest. Impact damage was visible on the left wing leading edge, ahead of the Pitot tube mounting location which had exposed the composite skin underneath the paint. This exposed section of skin continued aft on the bottom surface of the wing to the trailing edge. A portion of the Pitot tube near this exposed section had also been separated from its mounting location. The left wing lower skin also exhibited impact damage directly above the left main landing gear where the left main landing gear had penetrated the bottom of the left wing and left main fuel tank. The nose landing gear had separated from the airplane, and two of the blades on the four-bladed propeller were bent back. Both the left and right wing flaps had remained attached to their mounting locations, with the right wing flap being bent back on the outboard portion, and the left wing flap also displaying impact damage. The fuselage was damaged from the CAPS deployment and displayed peeling of a composite strip layer (as designed) on both sides of the fuselage. Further examination of the airplane revealed that the wing flaps were in the 100 percent (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 to be in a position approximately 2 inches forward of the idle "CUTOFF" position. ADDITIONAL INFORMATIONSafety Improvements In order to improve safety, Cirrus aircraft began the process of adding expanded mixture management procedures to the pilot operating handbooks for the SR20, SR22, and SR22T, for use by pilots. This guidance has and will be added upon the revision update of each POH. . FLIGHT RECORDERSThe accident airplane did not have a flight recorder installed nor was one required to be installed under the applicable CFRs. It did however have data recording capability incorporated in the Primary Flight Display and Multi-Function Display. The Primary Flight Display (PFD) The PFD unit included a solid state Air Data and Attitude Heading Reference System (ADAHRS) and displayed aircraft parameter data including altitude, airspeed, attitude, vertical speed, and heading. The PFD unit had external pitot/static inputs for altitude, airspeed, and vertical speed information. The PFD contained two flash memory devices mounted on a riser card. The flash memory stored information the PFD unit used to generate the various PFD displays. Additionally, the PFD had a data logging function, which was used by the manufacturer for maintenance and diagnostics. Maintenance and diagnostic information recording consisted of system information, event data and flight data. The PFD exhibited damage to the lower left control knob but was otherwise undamaged. The damage to the lower left control knob did not permit the NTSB to make selections within the PFD's internal menu when powered on. The PFD was therefore dismantled and the unit's data card was removed and installed in a surrogate unit. The surrogate unit functioned normally with the installed data card and the data was downloaded using an NTSB laboratory procedure. The PFD recording contained records of 25 power cycles. The accident flight was associated with the 22nd power cycle. The duration of the 22nd power cycle was approximately 2 hours and 38 minutes. Timing of the PFD data was measured in seconds from power-on. The Multi-Function Display (MFD) The MFD unit was able to display the pilot checklist, terrain/map information, approach chart information and other aircraft/operational information depending on the specific configuration and options that were installed. One of the options available was a display of comprehensive engine monitoring and performance data. The MFD contained a compact flash (CF) memory card located in a slot on the side of the unit. This memory card contained all of the software that the MFD needed to operate. Additionally, this card contained all of the checklist, approach charts, and map information that the unit would use to generate the various cockpit displays. During operation, the MFD display received information from several other units that were installed on the aircraft. Specifically, the MFD received GPS position, time and track data from the aircraft's GPS receiver. The MFD also received information from the aircraft concerning altitude, engine and electrical system parameters, and outside air temperature. This data was also stored on the unit's CF memory card. The MFD CF card contained 105 data files. One data file was identified as recorded during the incident flight. The data file was approximately 2 hours and 38 minutes in duration. Review of PFD and MFD Data The recorded data began at 14:56 and ended at 17:41. Data showed that the airplane performed a normal takeoff and climb. The airplane then entered a slower than normal cruise flight for the first portion of the recording. During the first portion of the cruise flight, between 15:24 and 15:59, the engine was at a low power setting with the recording showing an average of around 2,000 rpm. Around 15:59, the airplane began a series of high performance 360 degree turns. During this time the pilot utilized various higher power settings which resulted in higher rpm recordings. The pilot performed eight 360 degree turns. During the eight 360 degree turns, recorded vertical acceleration showed an average of about 2 Gs during most maneuvers. During the sixth and seventh 360 degree turns, the airplane reached about 70 degrees of bank angle. During the eighth 360 degree turn, vertical acceleration was recorded at a peak of approximately 3.3 Gs. During this turn, the airplane reached nearly 80 degrees of bank. The recorded rpm setting remained steady around 2,700 rpm during most of the high rate 360 degree turns. At approximately 16:47:35, the pilot performed an aileron roll to the left. The airplane entered this maneuver from approximately a level attitude. During this maneuver, the airplane experienced about 2.5 positive Gs (+2.5) and 0.5 negative Gs (-0.5). As the airplane completed the roll, the pitch became close to -30 degrees and rpm was reduced to under 2,000 rpm. As the airplane stabilized, the rpm returned to about 2,500 rpm. The loss of altitude during this maneuver was about 900 feet. At approximately 16:51:36, the pilot performed a second aileron roll to the left. The airplane entered this maneuver from a positive pitch attitude of about 19 degrees while pulling approximately 2.7 Gs in vertical acceleration. During the roll, the airplane experienced about 2.5 positive Gs (+2.5) and 0.5 negative Gs (-0.5). The pitch and rpm setting were more stable throughout as compared to the first roll. As the pilot completed the maneuver, a high performance 360 degree turn was immediately entered to the left. During this 360 degree turn, vertical acceleration averaged about 2.0 Gs. The flight continued with a low rpm setting of about 2,000 RPM and a recorded airspeed of about 100 knots. During this last portion of cruise flight the altitude varied between 6,000 and 7,000 feet. The airplane began to descend around 17:30. The rpm initially increased slightly during the descent, but later decreased to under 2,000 rpm for the remainder of the flight. The aircraft continued to descend until about 17:34:33 when the CAPS deployed which caused excursions in pitch and roll, among other flight parameters. At the time of CAPS deployment, pressure altitude indicated 1,928 feet. Review of recorded engine parameters revealed that during the entire flight. Engine rpm, oil pressure, fuel flow, manifold pressure, cylinder head temperature (CHT) and exhaust gas temperature (EGT) appear to respond nominally when viewed in relation to each other during the cruise portion of flight. Around 16:51:44, there was a rapid, but brief, drop in recorded oil pressure (32 psi). This occurred during the negative G portion of the second aileron roll. The flight continued normally until the airplane began to descend for landing. Recorded data showed manifold pressure was reduced as well as fuel flow. Two distinct drops in EGT were noted just prior to CAPS activation. As the airplane was descending, data shows an excitement of the vertical G parameter begin 17:32:38. A few seconds later, manifold pressure and fuel flow begin to decrease. EGT for cylinders 1 through 6 showed a distinct drop at 17:32:48 and recovery by 17:33:30. Immediately thereafter, a second distinct drop in EGT for cylinders 1 through 6 was noted. Engine data from the MFD terminated at 17:34:24. Review of CAPS Data Review of CAPS data revealed that the CAPS activated on the airplane approximately 0.76 nautical miles from the threshold of runway 29. Indicated airspeed at the time of deployment was approximately 82 knots, and the airplane was in a generally wings level attitude. True altitude at time of deployment was approximately 2,048 feet above mean sea level (msl). Ground elevation at the approximate location of activation was 1,411 feet msl. CAPS deployment height was approximately 637 feet above ground level. TESTS AND RESEARCHEngine and Fuel Injection System Most small airplanes are designed with spark ignition reciprocating engines. The name is derived from the back-and-forth, or reciprocating, movement of the pistons that travel the length of the cylinders to convert linear motion into the rotary motion of the crankshaft which produces the mechanical energy necessary to accomplish work. Reciprocating engines operate on the basic principle of converting chemical energy (fuel) into mechanical energy. This conversion occurs within the cylinders of the engine through the process of combustion which occurs when a spark plug ignites a pre-mixed fuel/air mixture (Fuel/air mixture is the ratio of the "weight" of fuel to the "weight" of air in the mixture to be burned.), of which in this case, the fuel was delivered by a fuel injection system controlled by the pilot through the use of manual mixture control lever in the cockpit. Review of the airplane's fuel system revealed that the airplane was equipped with an 81-gallon usable wet-wing fuel storage system that provided fuel for engine operation. The system consisted of a 42-gallon capacity (40.5 gallon usable) vented integral fuel tank and a fuel collector/sump in each wing, a three position selector valve, an electric boost pump, and an engine-driven fuel pump. Fuel would gravity fed from each tank to the associated collector sumps where the engine-driven fuel pump would draw fuel through a filter and selector valve to pressure feed the engine's continuous flow fuel injection system's fuel control unit (FCU). The fuel would then then flow from the FCU to the fuel manifold valve where it was distributed to the six fuel injector nozzles. Fuel would enter the fuel pump at the swirl well of the vapor separator. Here, vapor would be separated by a swirling motion so that only liquid fuel was fed to the pump. The vapor would be drawn from the top center of the swirl well by a small pressure-jet of fuel and would be fed into the vapor return line. This line would carry the vapor back to the fuel tank. There were no moving parts in the vapor separator, and the only restrictive passage used was in connection with vapor removal. Thus, there was no restriction of main fuel flow. The use of a positive displacement, engine-driven fuel pump meant that changes in engine speed would affect total pump flow proportionally, and since the fuel pump provided greater capacity than was required by the engine, a recirculation path was provided. A calibrated adjustable orifice and a relief valve located in this path would maintain the pump delivery pressure proportional to engine speed. These provisions assured proper pump pressure and delivery for all engine operating speeds. A check valve was also provided so that boost pu
The pilot’s improper in-flight fuel mixture management and failure to use the appropriate checklist or manuals during approach to landing, which resulted in a loss of engine power.
Source: NTSB Aviation Accident Database
Aviation Accidents App
In-Depth Access to Aviation Accident Reports
