N88MV

HISTORY OF FLIGHTOn October 30, 2017, about 1416 Pacific daylight time, a Vans Aircraft experimental, amateur built RV-6 airplane, N88MV, impacted a fence in a vineyard during a forced off-airport landing near Selma, California. The airline transport pilot was uninjured. The wings and fuselage incurred substantial damage. The airplane was registered to and operated by the pilot as a Title 14 Code of Federal Regulations Part 91 personal flight. Visual meteorological conditions prevailed at the time of the accident and no flight plan had been filed. The local flight originated from Fresno Chandler Executive Airport (FCH), Fresno, California about 1346.

According to the pilot, after takeoff, he proceeded west to climb above the Fresno Yosemite International Airport (FAT), Fresno, California and verified his transponder operation with Fresno Approach. He then headed towards the west/southwest. About 15 to 20 minutes later, the pilot began a descent to get below the FAT Class C airspace, and return to FCH. At an altitude of about 4,000 ft, the pilot noticed that the airplane batteries, located in the cockpit near his right foot, were getting hot. The pilot switched the engine monitor display to check the electrical system values, and saw that the indicated voltage was 15.5 volts, and that the indicated current was just above 30 amperes. At that point, the engine suddenly lost all power, but the propeller continued to windmill.

The pilot made some abbreviated and unsuccessful attempts to restore power, but then turned his attention to landing the airplane. He determined that the nearest airport was Selma Airport (0Q4), Selma, California which was about 10 miles away, and he began a gliding descent towards that airport. He communicated his situation and plans to a Fresno Approach controller. When the airplane altitude was about 1,000 ft, the pilot determined that he would not be able to reach 0Q4, and selected a road as his intended off-airport landing site. At that time, the only traffic on that road was an oncoming truck, but as the pilot continued the descent, he became uncertain whether the airplane would have sufficient altitude to clear the truck. The pilot then offset his flight path to the side of the road, in order to ensure that he would clear the truck. The truck passed the airplane, and the pilot then turned left and underflew some powerlines in an attempt to line up with, and land on, the road. That effort was unsuccessful, and the airplane touched down in a vineyard on the other side of the road. The airplane nosed over, and came to rest inverted. The pilot escaped the airplane by breaking the canopy. Although there was fuel leaking from the airplane, there was no fire. Federal Aviation Administration (FAA) inspectors examined the airplane at the site, and the airplane was recovered and transported to a secure facility for further examination. PERSONNEL INFORMATIONThe pilot held commercial, airline transport, and flight instructor certificates, and airplane single- and multi-engine land and instrument ratings. He reported a total flight experience of 2,700 hours, including 300 hours in the accident airplane make and model. His most recent flight review was completed October 2017, and his most recent FAA first-class medical certificate was also issued in October 2017. AIRCRAFT INFORMATIONThe airplane was constructed in 2000 by another individual, and that individual sold it to the accident pilot in February 2013. At the time of the pilot's purchase, the airplane was equipped with a Lycoming O-360 series engine, and a Hartzell 2-blade constant speed propeller. According to the pilot, when he acquired the airplane, the airframe and engine had each accumulated a total time (TT) in service of 1,100 hours. The pilot put about 300 hours more on the airplane, and then decided to modify it with some significant system and engine changes.

The pilot reported that the engine of the as-purchased airplane was equipped with a carburetor and a conventional magneto ignition system. He decided to change those systems to electronic versions for "performance and efficiency improvements." The pilot purchased a non-certificated kit that included an electronic fuel injection system, and replaced the magnetos with a fully electronic ignition system. The kit included the necessary wiring diagrams and instructions. The pilot performed the installations, and he reported that he had very few questions (of the manufacturers or vendors) regarding the installation details.

The pilot also reported that the as-purchased airplane had a "very basic visual flight rules (VFR) avionics package" that he replaced with an updated avionics suite. He purchased and installed a Garmin G3X system that presented flight instrumentation, position, navigation, communication, and other information using flat-panel color display(s). He purchased a pre-fabricated wiring harness to help expedite his G3X installation effort. He also installed two EARTHX-brand lithium-ion batteries as part of the modifications. None of these components met any FAA technical approvals such as Technical Standard Orders (TSO), nor were they required to do so.

About 5 weeks before the accident, the pilot had essentially completed the avionics and engine modifications, and then began ground runs of the engine and avionics in order to configure and test the new installations. Prior to the accident flight, he had put about 1.5 to 2 hours of ground run time on the engine, and had also conducted two uneventful but brief test flights. The accident flight was the third flight with the new systems, and the engine power loss occurred about 25 minutes into that flight. METEOROLOGICAL INFORMATIONThe 1415 automated weather observation at FCH, located about 10 miles north of the accident location, included calm winds, visibility 9 miles, clear skies, temperature 23° C, dew point 12° C, and an altimeter setting of 29.77 inches of mercury. AIRPORT INFORMATIONThe airplane was constructed in 2000 by another individual, and that individual sold it to the accident pilot in February 2013. At the time of the pilot's purchase, the airplane was equipped with a Lycoming O-360 series engine, and a Hartzell 2-blade constant speed propeller. According to the pilot, when he acquired the airplane, the airframe and engine had each accumulated a total time (TT) in service of 1,100 hours. The pilot put about 300 hours more on the airplane, and then decided to modify it with some significant system and engine changes.

The pilot reported that the engine of the as-purchased airplane was equipped with a carburetor and a conventional magneto ignition system. He decided to change those systems to electronic versions for "performance and efficiency improvements." The pilot purchased a non-certificated kit that included an electronic fuel injection system, and replaced the magnetos with a fully electronic ignition system. The kit included the necessary wiring diagrams and instructions. The pilot performed the installations, and he reported that he had very few questions (of the manufacturers or vendors) regarding the installation details.

The pilot also reported that the as-purchased airplane had a "very basic visual flight rules (VFR) avionics package" that he replaced with an updated avionics suite. He purchased and installed a Garmin G3X system that presented flight instrumentation, position, navigation, communication, and other information using flat-panel color display(s). He purchased a pre-fabricated wiring harness to help expedite his G3X installation effort. He also installed two EARTHX-brand lithium-ion batteries as part of the modifications. None of these components met any FAA technical approvals such as Technical Standard Orders (TSO), nor were they required to do so.

About 5 weeks before the accident, the pilot had essentially completed the avionics and engine modifications, and then began ground runs of the engine and avionics in order to configure and test the new installations. Prior to the accident flight, he had put about 1.5 to 2 hours of ground run time on the engine, and had also conducted two uneventful but brief test flights. The accident flight was the third flight with the new systems, and the engine power loss occurred about 25 minutes into that flight. WRECKAGE AND IMPACT INFORMATIONThe airplane came to rest inverted in a vineyard, about 6 miles west of 0Q4. The pilot was able to exit due to the resting attitude of the airplane, which allowed sufficient ground clearance beneath the canopy. The fuselage, wings and horizontal stabilizers sustained substantial damage.

During the initial post-accident inspection by FAA personnel, no non-impact related damage was noted. The fuel tanks were not compromised, and they contained sufficient fuel for continued flight.

The alternator was an automotive model with an integral voltage regulator. The

nut and stud assembly that was used to attach the primary alternator ground cable to the alternator was found to be secure, and the cable terminal was securely attached to that stud. However, the swaging of the ground cable to that terminal was loose. Black residue, consistent with arcing and fretting, was present at the conductor-to-terminal junction. The appearance was consistent with that residue having been caused by the looseness of the crimp (swage), and as having been loose for an extended period prior to the accident.

The cockpit circuit breaker for the alternator was rated at 60 amperes. It was the flush-when-set type, without the tall head that would allow manual tripping (breaking the circuit) by the pilot. The circuit breaker was found in the non-tripped position.

No other pre-impact anomalies with the airplane or engine were observed. The G3X device was removed from the airplane and sent to the NTSB facilities in Washington DC for data download. ADDITIONAL INFORMATIONG3X Data

The G3X device was successfully downloaded by NTSB personn...