NTSB Factual Report

HISTORY OF FLIGHT

On March 12, 2016, about 0847 eastern standard time, an experimental amateur-built Vans RV-8A, N838RV, was substantially damaged after it impacted the ground following a total loss of engine power near Clermont, Florida. The private pilot and passenger were fatally injured. The airplane was privately owned and operated under the provisions of Title 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed, and no flight plan was filed for the local personal flight, which originated from Spruce Creek Airport (7FL6), Port Orange, Florida, about 0825, and was destined for Winter Haven's Gilbert Airport (GIF), Winter Haven, Florida.

Two witnesses near the accident site reported seeing an airplane that matched the description of the accident airplane. They stated they did not hear any sound from the airplane as it flew overhead. One witness stated that the airplane made a "sharp" left turn and that the nose dropped before the airplane descended out of sight. The wreckage was subsequently located in an open field adjacent to a residential area.

According to radar track data, the airplane was flying on a southerly heading about 2,100 ft mean sea level (msl) about 3 miles from the accident site. The pilot of a nearby airplane reported that, around the time of the accident, he heard the pilot of an RV airplane transmit a mayday radio call saying that he had "lost an engine."

PERSONNEL INFORMATION

The pilot held a private pilot certificate with ratings for airplane single-engine land and instrument airplane. According to Federal Aviation Administration (FAA) records, the pilot was issued a repairman experimental aircraft builder certificate on August 25, 2003, for the accident airplane. His most recent third-class FAA medical certificate was issued on July 8, 2014; on the application for that certificate, he reported 880 total hours of flight experience with 12 hours in the previous 6 months. The pilot's flight experience at the time of the accident could not be determined.

The passenger was a student pilot and held an airframe and powerplant mechanic certificate. His most recent FAA third-class medical certificate was issued on September 23, 2015. At that time, he reported 25 total hours of flight experience.

AIRCRAFT INFORMATION

The two-seat, low-wing, fixed tricycle-gear airplane was assembled from a kit and issued an FAA experimental airworthiness certificate in 2002. It was powered by a Superior XP-400, 215-horsepower, experimental kit engine, equipped with a Whirl Wind two-blade constant-speed propeller.

The first entry in the engine logbook was on January 15, 2016, describing the installation of the new engine at 522.5 tachometer hours. The entry noted that the engine was run for 3 hours following assembly before installation. The last entry in the logbook was on January 31, at 531.6 tachometer hours; the oil had been changed and there were no contaminants found in the filter.

An Advanced Flight Systems Inc., AF-5800 electronic flight instrument system was installed in the airplane. The device was capable of displaying aircraft altitude, heading, moving maps, and engine information depending on options and installation. The unit recorded about 50 discrete data parameters to internal non-volatile memory. The device recorded data from flights between February 12 and March 12, totaling about 11 hours of flight time. About 18 minutes of the accident flight was recorded; the last data point was about 17 miles northeast of the accident site.

Given the logbook entries and the AF-5800 data, the estimated total engine time since installation was about 20 hours. A written record of flight time between January 31 and February 12 was not located.

METEOROLOGICAL INFORMATION

At 0853, the weather reported at Executive Airport (ORL), Orlando, Florida, located 19 miles east of the accident site, included clear skies and wind from 130° at 9 knots, 10 statute miles visibility, temperature 22°C, dew point 19°C, and an altimeter setting of 30.18 inches of mercury.

WRECKAGE AND IMPACT INFORMATION

The airplane came to rest in an open field about 307 ft msl. The field was about 2,400 ft long and about 200 ft wide; oriented east to west. There were powerlines on the eastern edge of the field and a road on the western edge. The wreckage was examined at the accident site and all major components were accounted for at the scene. The wreckage path was 30 ft long from an initial ground scar to the main wreckage and was oriented in a westerly direction. The wreckage came to rest upright on a magnetic heading about 110°.

The right wing was intact and attached at the fuselage; the aileron and flap remained attached to the wing. The left wing spar was fractured at the fuselage, the left flap connecting rod was fractured, and the left aileron was separated from the wing. The left wingtip was separated from the airplane and located at the first observed ground scar. The rudder and vertical stabilizer were attached and undamaged. Both the left and right elevators displayed crinkling from the outboard portions inward. Flight control continuity was established from the ailerons, elevator, and rudder surfaces to the cockpit controls. The cockpit was heavily damaged and folded open; the canopy was separated and lay over the right horizontal stabilizer.

One of the two composite propeller blades was fractured and found partially buried in the ground; the other blade remained intact and was undamaged. Both fuel tanks were breached and no residual fuel was observed; the fuel selector was positioned to the left main fuel tank. The engine-driven fuel pump sustained minimal damage and operated normally during a functional test. The fuel nozzle injectors were removed; they showed normal operational signatures and no obstructions. The fuel injection lines were intact and free from obstructions. Metal debris was present in the oil sump finger screen and the oil sump.

The propeller governor, fuel servo, and engine-driven fuel pump were removed and the engine was placed on a stand for testing. The mixture control lever and throttle metering unit moved freely.

The oil pump could not be rotated by hand; the oil pump was removed from the accessory case and exhibited impact to the driveshaft. The drive and gear exhibited normal operation signatures. The oil pump cavity was free of any scuffing or scoring and exhibited normal operating signatures. The oil filter was cut off; the paper element contained metal debris. The engine could not be rotated by hand. The camshaft exhibited normal operating signatures and the crankshaft was fractured.

The fractured crankshaft was forwarded to the NTSB Materials Laboratory, Washington, D.C., for examination. Visual examinations of the fractured surface revealed extensive beach markings and a finely-textured surface indicative of fatigue progression from the vicinity of the connecting rod journal.

Further examination revealed that the crankshaft fractured at the forward radius of the No. 2 connecting rod journal, opposite the top-dead-center position of the piston. Scanning electron microscopy (SEM) further revealed markings consistent with fatigue progression from a subsurface location. SEM examinations also revealed extensive mechanical damage consistent with crack closure and crack face recontact that obliterated the fine details of the fracture.

Energy dispersive x-ray spectra and maps of the origin location did not indicate an inclusion or chemical variations in the area. Metallographic cross sections did not reveal any inclusions of foreign material.

MEDICAL AND PATHOLOGICAL INFORMATION

The Office of the Medical Examiner, Leesburg, Florida, performed an autopsy of the pilot. The cause of death was listed as multiple blunt force injuries.

The FAA Bioaeronautical Sciences Research Laboratory, Oklahoma City, Oklahoma, conducted toxicological testing of specimens from the pilot. The testing was negative for ethanol and drugs of abuse. Acetaminophen, clopidogrel, metoprolol, rosuvastatin, ticlopidine, and zolpidem were detected in urine and blood.

Acetaminophen is an over-the-counter analgesic. Clopidogrel is an antiplatelet medication used to prevent heart attacks and strokes. Metoprolol is a beta-blocking agent used to treat high blood pressure and reduce the risk of recurrent heart attacks. Rosuvastatin is used to treat high cholesterol and related conditions. Salicylate is a metabolite of aspirin. Ticlopidine is a prescription platelet aggregation inhibitor. None of these medications are considered to be impairing. Zolpidem is a prescription medication used in the treatment of insomnia. This medication may impair mental and/or physical ability required for the performance of potentially hazardous tasks (e.g., driving, operating heavy machinery). Due to adverse side effects, the FAA recommends waiting at least 24 hours after use before flying.

NTSB Probable Cause

The pilot's exceedance of the airplane's critical angle of attack while maneuvering for a forced landing; which resulted in an aerodynamic stall and loss of control. Contributing to the accident was the fatigue failure of the crankshaft for reasons that could not be determined based on the available information.