NTSB Factual Report

HISTORY OF FLIGHT

On April 30, 2015, about 1257 mountain daylight time, an experimental amateur-built Hoffman Zenith 701, N95MH, sustained substantial damage when it impacted terrain about 2.5 miles north of Trinidad, Colorado. The non-certificated pilot received fatal injuries. The airplane was registered to a private individual and was operated by the non-certificated pilot under the provisions of the 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed at the time of the accident. No flight plan was filed. The time and place of departure, and the destination airport, are unknown.

A witness who lived near the accident site reported the he heard the airplane approaching from the east and he went outside to observe the airplane. He saw the airplane making two left hand circles overhead about 200 to 300 feet above ground level. He could see the pilot wearing a headset and sunglasses. The engine was running normally and was "revved out." The witness reported that on the third circle, the airplane "floated." He stated that the pilot was turning the airplane by using the rudder, the wings were not banked to the left, and the airspeed was low. He reported that the engine noise stopped, and the airplane flipped over to the left and went straight down. He reported that the nose of airplane rose slightly before ground impact.

PERSONNEL INFORMATION

The 53-year-old pilot was not a certificated pilot and he did not hold a medical certificate. The pilot did not possess a valid driver's license, but did have a valid Colorado identification card. The pilot's flight time was unknown.

AIRCRAFT INFORMATION

The airplane was an experimental amateur-built Hoffman Zenith 701, serial number 001, manufactured in 2009. The engine was a 100-horsepower Rotax 912 ULS-2, serial number 5651969. It seated two and had a maximum gross weight of 1,100 lbs. The maintenance logbooks were not obtained during the investigation. The hour meter on board the airplane indicated that it had a total of 435 hours. The airplane was equipped with a Dynon EFIS-D10A, a 4-inch flight instrument display.

The airplane's fuselage and wings were originally painted in red, yellow, and white. The horizontal stabilizer was painted red, the vertical stabilizer was painted yellow, and the rudder was painted in a white and black checkerboard pattern. Witnesses reported that the pilot was in an earlier accident in the airplane in 2014 that resulted in substantial damage to the nose gear, engine compartment, and both wings of the airplane. Both wings were replaced and the nose and engine compartment was repaired. The airplane was then painted white.

METEOROLOGICAL INFORMATION

At 1354, the surface weather observation at Perry Stokes Airport (TAD), Trinidad, Colorado, located about 10 miles to the northeast of the accident site, was: wind variable at 3 kts; visibility 10 miles; sky clear; temperature 25 degrees C; dew point -1 degrees C; altimeter 30.01 inches of mercury.

WRECKAGE AND IMPACT INFORMATION

The examination of the accident site revealed that the airplane impacted the terrain on a heading of 55 degrees magnetic. The wreckage was about 12 feet from the initial impact point and was inverted. The wreckage exhibited significant crushing and buckling, but it was largely intact.

The nose wheel was pushed aft. The leading edges and the bottoms of the left and right wings exhibited aft crushing and buckling. The cockpit was crushed aft. The floorboards had been cut by the first responders. The fuselage and empennage exhibited buckling, but the horizontal and vertical stabilizers received minimal damage. The check of the flight controls revealed that the rudder cables exhibited continuity from the rudder pedals to the rudder bellcrank. The elevator push/pull tube was separated at the bottom of the control stick with a fracture surface consistent with overload; otherwise, the elevator cables and attach points exhibited continuity. The aileron control system exhibited continuity from the control stick to the attach points on the left and right ailerons.

The leading edges of the three-bladed composite propeller blades revealed minimal damage. One blade remained attached to the propeller hub and it was not visibly damaged. One blade was separated from the propeller hub at the base of the blade. No other damage was noted. The third blade was broken about 10 inches from the blade root.

The engine exhibited minimal damage. The crankshaft was rotated and thumb compression and suction were confirmed on all four cylinders.

The cockpit fuel selector was found on the right tank. Both the fuel tanks were inverted and had little fuel in either tank when examined. The right tank had less that a pint of fuel drained from it. The ground underneath both fuel tanks was examined, and it was wet and smelled like aviation fuel.

The examination of the wreckage revealed that almost the entire airplane had been painted white, with only two large squares on the top of the fuselage still painted yellow. There were no aircraft registration numbers painted on the sides or tail of the airplane. The airplane's data plate indicated that the Federal Aviation Administration's register number for the airplane was N95MH.

The airframe and engine were taken to an airplane retrieval facility for further examination. The Dynon EFIS-D10A was sent to the National Transportation Safety Board's (NTSB) Vehicle Recorder Division for examination.

MEDICAL AND PATHOLOGICAL INFORMATION

The autopsy of the pilot was performed at the El Paso County Coroner's Office, Colorado Springs, Colorado, on May 2, 2015. The cause of death was multiple blunt force injuries. A Forensic Toxicology Fatal Accident Report was prepared by the FAA Civil Aerospace Medical Institute. Diphenhydramine was detected in the urine and blood. Naproxen was detected in the urine. Carbon monoxide (12%) was detected in the blood.

Diphenhydramine is a sedating antihistamine used to treat allergy symptoms and as a sleep aid. It is available over the counter with the names Benadryl and Unisom (as well as many others). Naproxen is an anti-inflammatory analgesic available over the counter with the name Aleve.

TESTS AND RESEARCH

The NTSB Vehicle Recorder Division examined the Dynon EFIS-D10A. Depending on the firmware version of the unit, the Dynon has the ability to log data to internal memory. According to the manufacturer, the firmware versions 5.0 and later have the ability to log certain parameters. However, upon interrogating the unit using the manufacturer's software, it was determined that the unit had version 2.19, which does not support data logging. Therefore, there was no data recorded on the device.

The airplane's fuel system was examined and it exhibited continuity from the fuel tanks in the wings to the engine. The breaks in the fuel lines were consistent with impact damage. The Facet automotive fuel pump was tested and it operated when electrical power was applied.

An engine run was conducted and the engine started immediately and it ran smooth. However, due to the impact damage to the oil pump fixture, the engine was only run at idle power and for a short duration. The engine run was conducted a second time with the same results.

ADDITIONAL INFORMATION

The current owner of the airplane purchased the airplane in April 2014. On December 11, 2014, the airplane owner reported to the Longmont Police department that the airplane was missing and it was described as "Lost Property." On December 24, 2014, the owner made a written statement indicating that he was the sole owner of the airplane and that he reported the theft of the airplane to the Longmont Police Department. The written statement did not authorize the accident pilot to be in possession of the airplane.

NTSB Probable Cause

The noncertificated pilot's failure to maintain airspeed following a loss of engine power while maneuvering at a low altitude, which resulted in the airplane's wing exceeding its critical angle-of-attack and a subsequent aerodynamic stall. The reason for the loss of engine power could not be determined because postaccident examination revealed no evidence of mechanical failure or malfunction.