NTSB Factual Report

HISTORY OF FLIGHT

On March 7, 2015, at an unknown time, an Ahrens RV-6 experimental amateur-built airplane, N4074V, was substantially damaged when it nosed over while landing at a private airstrip southeast of Pratt, Kansas. Visual meteorological conditions prevailed on the day of the accident. The commercial pilot, the sole occupant on board, was fatally injured. The personal flight was being conducted under the provisions of 14 Code of Federal Regulations Part 91 without a flight plan. The cross country flight departed Lucas, Kansas, at an unknown time and was en route to Pratt, Kansas.

According to a friend of the pilot, the pilot had departed about 0930 the morning of the accident and intended to fly to Lucas, Kansas. The wreckage of the airplane was initially spotted by an airplane flying over the private airstrip about 1530. The accident airplane was observed to be inverted on the east side of the runway. Law enforcement officers were notified and found the pilot deceased. There were no known witnesses to the accident.

PERSONNEL INFORMATION

The pilot, age 85, held a commercial pilot certificate with an airplane single engine land rating. The pilot did not hold a medical certificate at the time of the accident. He last applied for a third class medical certificate on July 13, 2013. The issuance of that certificate was deferred due to health concerns and the Federal Aviation Administration (FAA) Aerospace Medical Certification Division requested further information on August 28, 2013. On November 15, 2013, the pilot's undated response of "You win. Apparently I am done flying." was logged into the system. The pilot was sent a denial of his medical certificate application that day.

At the time of medical certificate application the pilot reported his total flight time as 3,099 hours, 16 hours of which had been logged in the previous six months. A pilot logbook with flight activity dates in 1995 and 1996 was located in the airplane. The pilot's most recent flight log was not located during the course of this investigation. Investigators were not able to establish the pilot's recent flight experience or when the last flight review was successfully completed.

Several acquaintances of the pilot told investigators that the pilot had recently commented that he was having depth perception issues and had been landing the airplane hard. The family reported that they were unaware of any medical issues or concerns with the pilot.

AIRCRAFT INFORMATION

According to FAA records, the 1995 Rans RV-6 experimental airplane (serial number 1) had been manufactured by Gerd Ahrens. It was registered with the FAA on a special airworthiness certificate for experimental operations. A Lycoming O-320-E3D engine, rated at 150 horsepower at 2,700 rpm, powered the airplane. The engine was equipped with a 2-blade propeller.

The airframe logbook was located in the airplane. A review of the maintenance records indicated that an annual/condition inspection had been completed on September 9, 2013, at an airframe total time of 1,092.36 hours. On March 10, 2014, at an airframe total time of 1,115.0 hours, Van's Aircraft Service Bulletins 14-02-05 and 14-01-31 were complied with – no cracks were found.

A copy of the engine logbook was provided by the sheriff. On July 13, 2014, at a tachometer time of 1,131 hours, the pilot changed the engine oil and filter, checked the engine, and removed and cleaned the carburetor air filter.

METEOROLOGICAL INFORMATION

The closest official weather observation station was Pratt Regional Airport (KPTT), Pratt, Kansas, located 9.4 nautical miles (nm) northwest of the accident site. The elevation of the weather observation station was 1,952 feet mean sea level (msl).

The routine aviation weather report (METAR) for KPTT, issued at 1135, reported wind calm, visibility 10 miles, sky condition clear, temperature 17 degrees Celsius (C), dew point temperature minus 4 degrees C, altimeter 30.29 inches.

The METAR for KPTT, issued at 1235, reported wind clam, visibility 10 miles, sky condition clear, temperature 18 degrees C, dew point temperature minus 5 degrees C, altimeter 30.28 inches.

The METAR for KPTT, issued at 1335, reported wind 260 degrees at 3 knots, visibility 10 miles, sky condition clear, temperature 19 degrees C, dew point temperature minus 5 degrees C, altimeter 30.24 inches.

The METAR for KPTT, issued at 1435, reported wind calm, visibility 10 miles, sky condition clear, temperature 20 degrees C, dew point temperature minus 6 degrees C, altimeter 30.20 inches.

The METAR for KPTT, issued at 1535, reported wind 240 degrees at 3 knots, visibility 10 miles, sky condition clear, temperature 21 degrees C, dew point temperature minus 6 degrees C, altimeter 30.19 inches.

AIRPORT INFORMATION

The private airstrip was southwest of the pilot's private residence at an elevation of 1,880 feet msl. The grass runway, oriented on a 17/35 heading, was about 1,900 feet in length and 50 feet wide.

WRECKAGE AND IMPACT INFORMATION

The accident site was located just to the east of the north/south grass strip. The accident site was at an elevation of 1,880 feet msl and the airplane impacted on a magnetic heading of 350 degrees.

Ground scars on the grass runway, which were consistent with the left and right main landing gear, were observed several hundred feet north of the approach end of runway 35. The ground scars tracked to the right and then off of the runway surface. The airplane came to rest inverted about 400 feet from the first documented touch-down-point. The canopy of the airplane was fragmented, the leading edge of both wings was impact-damaged, the firewall was wrinkled, and the vertical stabilizer tip was bent.

A total of 22 scars consistent with propeller strikes continued north from the initial touchdown point for 46 feet towards the main wreckage and between the two parallel ground scars. The ground scar consistent with the left main landing gear tire departed the runway 40 feet further where both parallel ground scars become wider and a deeper dirt displacement was observed. At the point the ground scars consistent with the propeller stops, one long continuous ground scar, consistent with the cowling airbox starts. This scar was 10 feet long with paint chips and composite fragments located within the scar. A circular ground scar consistent with the spinner of the airplane was located 7 feet from the end of the long continuous ground scar.

The main wreckage was located 20 feet from the last circular ground scar. The airplane came to rest inverted with the nose oriented to the south-southeast. The main wreckage included the engine, the fuselage, both wings, and the empennage. Both main landing gear and the tailwheel remained attached to the fuselage and empennage respectively. Fuel was dripping from both wing fuel tanks.

The fuselage included the fragmented portions of the canopy, the instrument panel, and the cabin. Other than the damage to the canopy, the fuselage did not exhibit any impact damage. The fuel selector valve was in the off position. The Kollsman window was set at 30.11 inches. The flaps were selected full down. The electronic tachometer read 1150.55.

The engine controls were found in the following positions:

Mixture control –rich

Throttle control –idle power

Carburetor heat –on

Magnetos – both

The right wing remained attached to the fuselage and included the right aileron and right flap. The outboard tip of the wing was cracked. The right flap was extended. Control continuity and correctness was established from the control stick outboard to the aileron.

The right main landing gear wheel pant exhibited leading edge impact damage and scratching. Dirt and grass were imbedded along the leading edge and into the damage. The wheel and tire rotated without hesitation and the tire was inflated. The tire exhibited a few scuff marks along the surface. Dirt and grass were embedded in the treads of the tire.

The airbox on the lower cowling, beneath the engine, exhibited impact damage and was embedded with dirt and grass. The spinner of the propeller exhibited rotational scoring, was impact damaged and fragmented, and had dirt and grass embedded at the tip. Both propeller blades separated partially from the engine and were fragmented.

The left wing remained attached to the fuselage and included the left aileron and left flap. The outboard leading edge of the wing was impact damaged. The left flap was extended. Control continuity and correctness was established from the control stick outboard to the aileron.

The left main landing gear wheel pant exhibited leading edge impact damage and scratching. Dirt and grass were imbedded along the leading edge and into the damage. The wheel and tire rotated without hesitation and the tire was inflated. The tire exhibited a few scuff marks along the surface. Dirt and grass were embedded in the treads of the tire.

The empennage included the horizontal and vertical stabilizers, the elevator, and the rudder. The top of the vertical stabilizer and rudder were impact damaged. The leading edge of the vertical stabilizer and the remaining portion of the rudder control did not exhibit impact damage. The joint between the horizontal stabilizer and elevator was impact damage. The leading edge of the horizontal stabilizer and the trailing edge of the elevator did not exhibit impact damage. Control continuity and correctness was established from the control stick in the cabin outboard to the elevator and from the rudder pedals in the fuselage outboard to the rudder.

The engine cowling was removed and the engine was examined. The top bank of spark plugs were removed and exhibited worn out normal signatures when compared to the Champion Check-A-Plug chart. The engine was rotated through at the propeller. Thumb compression was observed on all four cylinders. No binding or hesitation was observed or noted when the engine was rotated. There was no external damage to the engine.

After the airplane was righted, the brakes were examined and tested. The airplane was moved and right brake application, left brake application, and both brakes application were made. There were no anomalies or issues with the functionality of either brake assembly.

MEDICAL AND PATHOLOGICAL INFORMATION

The Regional Forensic Science Center – Sedgwick County, Kansas, performed the autopsy on the pilot on March 9, 2015. The autopsy concluded that the cause of death was mechanical asphyxia.

The FAA's Civil Aerospace Medical Institute (CAMI), Bioaeronautical Sciences Research Laboratory, Oklahoma City, Oklahoma, performed toxicological tests on specimens that were collected during the autopsy (CAMI Reference #201500050001). Results were negative for carbon monoxide and ethanol. Tests for cyanide were not performed. Testing of the blood and urine revealed Alfuzosin. According to the FAA website, this medication is used to treat benign prostatic hyperplasia and had no listed warnings.

NTSB Probable Cause

A hard landing, which resulted in the pilot’s loss of directional control and the airplane’s subsequent nose-over.