History of Flight
On June 2, 2009, at 1555 central daylight time, an experimental amateur-built Zenith Aircraft STOL CH 801, registration N1399X, was substantially damaged when it impacted trees after a loss of power on final approach at Copiah County Airport (M11), Crystal Springs, Mississippi. The certificated commercial pilot and certificated private pilot onboard were killed. Visual meteorological conditions prevailed, and no flight plan was filed for the local maintenance test flight conducted under 14 Code of Federal Regulations Part 91.
A witness reported that the accident airplane performed three "crow hops" before taking off from runway 17. It then climbed and joined the traffic pattern. As the airplane began its turn onto final approach from the left base leg, the engine was heard to stop. The airplane turned west, passed over pine trees, and then struck oak trees. The airplane collided with the ground, and a post-crash fire ensued.
Personnel Information
According to FAA records, the commercial pilot in the right seat held ratings for airframe and powerplant mechanic, repairman, flight instructor airplane single-engine, advanced ground instructor, commercial pilot airplane single-engine and multiengine land, and instrument airplane. His most recent FAA second-class medical certificate was issued on May 14, 2008, and he reported 2,670 total flight hours.
The private pilot in the left seat held ratings for airframe and powerplant mechanic, repairman, private pilot airplane single-engine and multiengine land. His most recent FAA third-class medical certificate was issued on October 9, 2007, and he reported 240 total flight hours.
Aircraft Information
The accident airplane was a high-wing, kit-built, single-engine monoplane of conventional construction, designed for short takeoff and landing (STOL) operations. It featured fixed leading edge slats and full-length flaperons. Power was provided by a 220-horsepower Franklin 6A-350-C1 engine.
FAA records indicate the airplane was sold to its builder as a kit on April 4, 2005, and issued a special airworthiness certificate on February 8, 2006. It was sold to the owner on January 17, 2008. The previous conditional inspection occurred in January 2008 before purchase, and the airplane had accrued approximately 68 total hours of operation at the time of the accident.
Meteorological Information
At 1553, the reported weather at Hawkins Field Airport (HKS), Jackson, Mississippi, about 27 miles north of the accident site, included: wind 170 at 6 knots, visibility 10 miles, few clouds at 7,000 feet, temperature 31°C, dew point 18°C, and an altimeter setting of 29.99 inches of mercury.
Airport Information
Copiah County Airport (M11) had one runway in a 17/35 configuration. Runway 17 was asphalt, in fair condition, with a length of 3,000 feet and a width of 75 feet. Multiple obstructions existed on the approach end of runway 17, including trees 66 feet high located 1,540 feet from the approach end and 100 feet left of the centerline. A 20:1 slope was required to clear the trees.
Wreckage and Impact Information
An FAA inspector reported that the airplane first contacted a tree, then "pancaked" into a field, followed by a post-impact fire. NTSB examination revealed the airplane came to rest inverted with crush, compression, and fire damage. No evidence of preimpact failure or malfunction of the airplane or engine was found.
Flight control continuity was established for all controls from the respective surfaces, rudder pedals, and control stick. The pitot-static system was unobstructed. The propeller showed no evidence of rotation during impact. The engine examination revealed the carburetor was fire-damaged, the throttle plate was full open, and the throttle arm was at full throttle. No intake blockages were found. The exhaust manifolds were light gray internally. Oil was present internally, the oil pump was functional, and the crankshaft rotated freely with compression on all cylinders. Both magnetos had impact and fire damage but showed no preimpact malfunction; spark plug electrodes were light gray.
The aircraft was equipped with four 15-gallon fuel tanks (two main, two auxiliary) with individual sending units and gauges. Fuel lines from each tank ran to a floor drain and then to a fuel selector valve allowing supply from main or auxiliary tanks. All four fuel filler caps were secured. The left main tank showed internal fire damage, the left auxiliary tank did not, the right main tank had no internal fire damage, and the right auxiliary tank was burned away.
Medical and Pathological Information
Autopsies were performed on both pilots by the Mississippi State Medical Examiners Office. Toxicological testing was conducted by the FAA Bioaeronautical Sciences Research Laboratory.
Tests and Research
Witnesses and FAA records indicated both pilots were certificated airframe and powerplant mechanics employed by a fixed base operator (FBO) providing maintenance and fuel handling at M11. The airplane was brought to the FBO for maintenance around April 10, 2009. At that time, the commercial pilot flew the airplane with the owner for about 40 minutes to "learn the airplane." The airplane exhibited a "right wing down" condition due to incorrect right wing dihedral. Consequently, mechanics drained the fuel, removed the right wing, replaced lift struts and fittings, and performed a conditional inspection to correct the issue.