N4223FCessna 172 · 1958

On July 17, 2014, about 2320 central daylight time, an Air Tractor AT-401B single engine turboprop airplane, N4223F, was substantially damaged after impacting terrain near Ellis, Kansas. The pilot was fatally injured. The airplane was registered to Frontier Ag Inc., and was operated by Frontier Agricultural Service, Inc.; both of Oakley, Kansas. Dark night visual meteorological conditions (VMC) prevailed at the time of the accident and a flight plan had not been filed for the 14 Code of Federal Regulations (C.F.R.) Part 91 positioning flight. The airplane had departed from Moritz Memorial Airport (K61), Beloit, Kansas, about 2245 and was destined for Oakley Municipal Airport (OEL), Oakley, Kansas.

No witnesses to the accident were found, however evidence at the scene showed an initial impact scar with wreckage debris scattered generally to the south. The fuselage came to rest upright about 200 feet south from the initial impact point. There was no postimpact fire.

The pilot, age 23, held a Federal Aviation Administration (FAA) commercial pilot certificate with a rating for airplane single engine land. He did not hold an instrument rating. His FAA private pilot certificate was issued on July 2, 2010, and his FAA commercial pilot certificate was issued on March 25, 2011. 2014.

An examination of selected pages from the pilot's personal logbook showed that it contained daily flight entries from June 11, 2011, through March 14, 2014. Other pilot logbooks were not available during the course of the investigation. Based on the logbook entries the pilot's flight experience on March 14, 2014, was estimated as: total pilot experience in all aircraft 1,313.9 hours; pilot experience in agricultural application 1,030.6 hours; pilot experience in turboprop airplanes 394.0 hours; and pilot experience in the accident airplane type 96.5 hours. The pilot had logged a total of 3.9 hours of experience in multi-engine airplanes, with the remainder of his total experience in single-engine airplanes. His only logged night flying experience in the previous two years was for one flight on February 24, 2014, and another flight on August 9, 2013. His only logged instrument flight experience in the previous two years was for two separate flights totaling 1.4 hours in December, 2013, which gave a career total of 11.4 hours of simulated instrument flying experience.

An endorsement in the pilot's logbook showed that he had completed the flight review required by 14 C.F.R. 61.56 on March 12, 2013. A certificate showed that the pilot had completed the agricultural pilot knowledge and skills test required by 14 C.F.R. 137.19 (b), (c), (d), (e) on March 31, 2013.

The single seat, low-wing, fixed conventional landing gear, single engine agricultural application airplane, serial number (s/n) 401B-1208, was manufactured in 2008. It was originally equipped with a 550-horsepower Pratt & Whitney R-1340 radial engine. At the time of the accident the airplane was equipped with a 740-horsepower Walter, model M601-E11, turbo-propeller engine, s/n 873002, which drove an Avia Propeller Ltd., model V 508E-AG/106/A, three-blade metal alloy propeller, s/n 21 065 1373.

The airplane was equipped with a SATLOC GPS system which drove a cockpit mounted light bar guidance system and a real-time graphic moving map display in the cockpit. The airplane was equipped an inclinometer or slip indicator, however it was not equipped with any of the other instruments required for instrument flight such as a gyroscopic rate-of-turn indicator; a gyroscopic pitch and bank indicator (artificial horizon); or a gyroscopic direction indicator (directional gyro). The airplane was not equipped with either an autopilot or an emergency locator transmitter (ELT), nor was it required to be.

Fuel records at K61 showed that the airplane had been self-service refueled with 73 gallons of Jet A fuel on the evening of the accident. A postaccident fuel quality inspection of the refueling facility at K61 was satisfactory.

The nearest automated weather observing system was at Hays, Kansas (KHYS) located about 14 miles southeast from the accident location at an elevation of 1,998 feet mean sea level (msl). At 2335 KHYS reported, visibility of 10 miles, broken clouds at 1,000 feet, broken clouds at 2,500 feet, overcast clouds at 3,300 feet, temperature 17 degrees Celsius (C), dew point 13 degrees C, with an altimeter setting of 30.10 inches of Mercury.

Other weather observations in the area indicated that there were instrument flight rules (IFR) ceilings at the time of the accident from central Kansas westward, with visual flight rules (VFR) ceilings from central Kansas eastward into Missouri. Given the overall weather pattern, the overall cloud ceiling was in a relatively stable height, but with the gradual upslope of the terrain, a southeasterly low-level wind, and gradual upslope flow, lowering IFR ceilings would have been expected as the flight progressed westward from eastern Kansas.

The weather observations were consistent with showing the accident flight had no weather issues after the departure about 2050 from Skyhaven Airport (KRCM), Warrensburg, Missouri, through the airplane's westbound refueling stop at K61 with cloud ceilings then at or above 9,000 feet above ground level (agl). Once departing K61, the cloud ceiling gradually lowered to 1,000 feet agl by KHYS with the cloud ceiling continuing to lower to 700 feet agl and below the closer the flight got to its intended destination at OEL.

AIRMET Sierra issued at 2145, and valid at the accident time near the accident flight level, forecasted IFR conditions for the accident site with ceilings below 1,000 feet and visibilities below 3 miles with precipitation and mist.

Astronomical data obtained from the United States Naval Observatory for the accident location indicated that sunset occurred at 2102 and moonrise occurred at 0026 on the following day. At the time of the accident the sun and the moon were both more than 15 degrees below the horizon and provided no ambient light.

There was no record that the pilot received a preflight weather briefing before departing K61 for OEL. There was no record of any radio communications from the pilot after his departure from K61.

During the late evening and early morning hours the operator and family members became concerned and notified the FAA that the airplane had failed to arrive. The FSS issued an alert notice (ALNOT) which directed an extensive communication search for the overdue, unreported, or missing aircraft. Local emergency responders discovered the wreckage after daybreak on the following morning and the ALNOT was cancelled.

The airplane impacted terrain about 2,175 feet msl on an agricultural field in a remote extremely sparsely populated area with no ground lighting in the area.

The initial ground scar, consistent with the right wingtip impact, was about 50 feet long on a bearing of about 167 degrees (magnetic), which ended in an impact crater about 12 to 18 inches deep. The separated propeller and one of the cockpit doors were found in the wreckage debris path south of this area. Ground scars and wreckage debris, curving to the west, led to the final resting location of the fuselage, which was located about 200 feet from the initial ground scar on a direction of 180 degrees magnetic.

The canopy and overhead structure/skid plate remained intact and showed less damage. The forward windshield, forward windshield brace tubes, instrument panel, rudder pedal assembly, and aft hopper wall were completely separated.

The fuselage was destroyed forward of the cockpit area. The occupiable space inside the cockpit compartment had not collapsed inward, but was open and completely exposed on the forward and right sides. The right sidewall of the cockpit was completely separated from the fuselage. The cockpit floor remained intact and in place. The fuselage structure below the cockpit floor was damaged and was mostly missing. The aft fuselage was bent in two places toward the left.

The completely detached upper instrument panel was found in the wreckage. The following instruments were present: airspeed, altimeter, compass, oil temp, oil pressure, propeller tachometer, Ng tachometer, hopper gauge, and slip indicator. There were several instrument holes that did not have instruments present and it could not be determined what instruments, if any, had been installed in those open locations. The Hobbs hour meter had become detached from the instrument panel and was not observed in the wreckage.

The airplane's wing center splice remained intact and undamaged. The right wing was destroyed with all ribs and skins detached from the spars. The right spar was impact bent with both spar caps (upper and lower) detached from the spar webs and bent aft.

The left wing main skins and trailing edge skins were damaged, but remained generally in place. The outboard leading edge skins were deformed aft and downward. The inboard leading edge skins had large dents and some deformation but primarily remained intact. The inboard end of the left wing integral fuel tank was impact ruptured.

The flap actuator was found in the fully retracted position. The flap actuator remained attached to the flap torque tube and to the fuselage frame. The two control arms remained attached to the ends of the flap torque tube and the pushrods remained attached to the control arms. The rudder pedals were separated from the fuselage in the wreckage, but both pedals remained attached to their hinge points. Rudder control continuity was confirmed.

Elevator control continuity was established from the control stick to the elevator horns.

The aileron controls were extensively damaged, making complete confirmation of control continuity difficult, but the control stick, aileron torque tube, upper pushrods and aileron drooping bellcranks remained installed and intact, although impact damaged. The drooping controls were damaged but all parts were observed at the scene

The long wing-mounted aileron pushrods had both been impact separated at their inboard ends. The aileron control continuity in the left wing could be confirmed by moving the inboard end of the long pushrod and observing proper movement of the aileron horn. The aileron horn was no longer attached to the aileron. Continuity of the aileron control system in the right wing could only be partially confirmed due to impact damage.

The plumbing of the fuel system could only be partially confirmed due to impact damage. The fuel shutoff valve was found and was confirmed to be in the "open" position.

Emergency responders reported smelling fuel at the scene. A visual examination of the accident scene three days after the accident showed a significant vegetation kill in the debris path area.

The engine was examined at the scene. All engine accessories remained attached and no obvious defects were noted.

The intact propeller was separated from the engine and was found in the wreckage debris path. The separated propeller drive flange displayed a 45-degree torsional shear lip at the fractured surface. All three propeller blades remained attached to the propeller hub. All three propeller blades exhibited ripples along the span of the trailing edge, significant leading edge gouging, and chordwise striations and smearing on both faces of the propeller blades. All three blades exhibited damage showing twisting and bending opposite the direction of rotation, and all three blades exhibited at least some evidence of S-curve bending..

The postaccident examination of the airframe, engine, and propeller revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation.

An autopsy was performed on the pilot by the Office of the District Coroner of the XXIII Judicial District of Kansas.

Forensic toxicology was performed on specimens from the pilot by the Federal Aviation Administration (FAA), Aeronautical Sciences Research Laboratory, in Oklahoma City, Oklahoma. The toxicology report stated: no carbon monoxide was detected in blood; tests for carbon monoxide were not performed; tests for cyanide were not performed; no ethanol was detected in vitreous: and no drugs were detected in urine.

FAA records showed the pilot's most recent unrestricted class two medical certificate was issued on January 7, 2014. At the time of the medical examination the pilot reported that he was taking no medications, he reported no new concerns, and no significant issues were identified by the aviation medical examiner.

An impact damaged Motorola "Droid" cellphone was removed from the wreckage and was examined at the NTSB vehicle recorder division in Washington, DC. Pertinent information could not be extracted and thus no download of data from the device was attempted.

A SATLOC M3 CPU device was removed from the wreckage and sent to the NTSB vehicle recorder division in Washington, DC. An examination of the device was conducted and GPS positional data was extracted.

The GPS data showed that the airplane departed K61 about 2245 and the airplane began to proceed toward OEL. The westbound airplane was maintaining a wandering cruise altitude that varied from about 3,700 feet mean sea level (msl) to about 3,200 feet msl until 2316, when the airplane began descending and made a turn to the left.

At 2317:37 the southbound airplane had descended to about 2,500 feet msl and began to slow. At 2319:03 the airplane began a second 90 degree left turn to an easterly track and the altitude increased to 3,205 feet msl where the underlying terrain was about 2,200 feet msl. The airplane was about 2,800 feet laterally to the northwest from the impact location, when at 2319:25, the last recorded GPS data point showed that the climbing airplane was then eastbound and the GPS ground speed had slowed to about 125 knots.

According to FAA Advisory Circular 60-4A "Pilot's Spatial Disorientation," "Surface references and the natural horizon may at times become obscured, although visibility may be above visual flight rule minimums. Lack of natural horizon or surface reference is common … in extremely sparsely populated areas or in low visibility conditions. A sloping cloud formation (or) an obscured horizon … can provide inaccurate visual information for aligning the aircraft correctly with the actual horizon. The disoriented pilot may place the aircraft in a dangerous attitude."

"… tests conducted with qualified instrument pilots indicated that it can take as long as 35 seconds to establish full control by instruments after a loss of visual reference of the earth's surface. AC 60-4A further states that surface references and the natural horizon may become obscured even though visibility may be above visual flight rules (VFR) minimums and that an inability to perceive the natural horizon or surface references is common during flights … in sparsely populated areas, and in low-visibility conditions".

According to the FAA "Instrument Flying Handbook", FAA-H-8083-5B, "An obscured horizon … can provide inaccurate visual information, or false horizon, for aligning the aircraft correctly with the actual horizon. The disoriented pilot may place the aircraft in a dangerous attitude".

"In moderate unusual attitudes, the pilot can normally reorient by establishing a level flight indication on the attitude indicator. However, the pilot should not depend on this instrument if … its upset limits may have been exceeded or it may have become inoperative due to mechanical malfunction ... As soon as the unusual attitude is detected, the recommended recovery procedures … should be initiated by reference to the ASI, altimeter, VSI, and turn coordinator".

According to the FAA "Airplane Flying Handbook", FAA-H-8083-3A, "The pilot should remember, that unless (instrument flying) tasks are practiced on a continuing and regular basis, skill erosion begins almost immediately. In a very short time, the pilot's assumed level of confidence will be much higher than the performance he or she will actually be able to demonstrate should the need arise".

"A VFR pilot is in IMC conditions anytime he or she is unable to maintain airplane attitude control by reference to the natural horizon, regardless of the circumstances or the prevailing weather conditions. (This situation) must be accepted by the pilot involved as a genuine emergency, requiring appropriate action".

According to the FAA "Instrument Flying Handbook", FAA-H-8083-15A, chapter 1, Human Factors, lists some of the illusions leading to spatial disorientation as follows:

"Somatogravic illusion - A rapid acceleration…..can create the illusion of being in a nose up attitude. The disoriented pilot will push the aircraft into a nose low, or dive attitude. A rapid deceleration by a quick reduction of the throttles can have the opposite effect, with the disoriented pilot pulling the aircraft into a nose up, or stall attitude.

Elevator illusion - An abrupt upward vertical acceleration, as can occur in a helicopter or an updraft, can shift vision downwards (visual scene moves upwards) through excessive stimulation of the sensory organs for gravity and linear acceleration, creating the illusion of being in a climb. The disoriented pilot may push the aircraft into a nose low attitude."

The FAA "Airplane Flying Handbook", FAA-H-8083-3A, chapter 10, states the following about night flying and its affect on spatial orientation:

"Night flying requires that pilots be aware of, and operate within, their abilities and limitations. Although careful planning of any flight is essential, night flying demands more attention to the details of preflight preparation and planning...Night flying is very different from day flying and demands more attention of the pilot. The most noticeable difference is the limited availability of outside visual references. Therefore, flight instruments should be used to a greater degree in controlling the airplane...Under no circumstances should a VFR night-flight be made during poor or marginal weather conditions unless both the pilot and aircraft are certificated and equipped for flight under…IFR..."