WPR15FA143

The pilot's attempt to depart in conditions that resulted in the airplane having insufficient performance capability, which resulted in a collision with a tree.

The private pilot and three passengers had landed at a remote airstrip earlier in the morning to visit the pilot's ranch. The published guidance for the airstrip noted that the runway was 2,500 ft long and 75 ft wide. After being on the ground about 2 hours 30 minutes, the pilot indicated to ranch personnel that he wanted to depart before the wind increased. Shortly thereafter, the airplane departed with an estimated 4- to 5-kt tailwind. During the initial climb, the nose landing gear and left tire impacted a tree (which was about 50 ft tall) located about 100 ft from the fence that made the perimeter of the runway. The left tire then likely impacted the left horizontal stabilizer and elevator, rendering the airplane uncontrollable. The airplane then descended into a creek and came to rest inverted; a postimpact fire ensued. There was no evidence of any mechanical malfunctions or failures with the airframe or engine that would have precluded normal operation. The performance data were calculated using the estimated airplane and environmental conditions at the time of the accident. The distance required to clear a 50-ft obstacle for a takeoff with a 5-kt tailwind from a dry grass runway similar to the accident runway was about 2,675 ft. The actual distance from the area where the pilot began the takeoff roll to the first impacted tree was about 2,625 ft, which indicates that the airplane did not have the sufficient performance capability to climb over the tree. The pilot frequently flew into the airstrip and was familiar with the terrain and departure procedures, and GPS data revealed that the pilot departed from the airstrip on nine prior occasions in the past year. Comparison of these flights to the accident flight revealed that the pilot's flightpath was normally to the right of the accident flightpath. The pilot likely would have not been able to see the tree due to the airplane's nose-high pitch configuration during the takeoff.

The Airport/Facility Directory (AFD), indicated that Upper Loon Creek USFS Airport runway 04 was about 2,500 ft long and 75 ft wide. The runway surface was composed of turf/dirt, and noted to be in fair condition. The airport elevation was 5,500 ft msl, and the AFD noted the obstructions for the runway to be a 70-ft tree 45 ft from the runway and 70 ft left of the centerline. In the remarks section of the AFD was a note "recommended for experienced mountain pilots only with trees and higher terrain on both ends." Local pilots stated that almost everybody will land on runway 22 and depart runway 04 due to the terrain. While on-site, investigators noted that the runway was in fact oriented on a bearing of about 051 degrees; following the accident, the FAA reflected the runway to be designated as 05/23. In June 1995, an accident (SEA95LA117) occurred at Upper Loon Creek where the pilot and passenger received minor injuries. According to the pilot involved in the accident, he was attempting to take off from runway 04 with an approximate 10 kt tailwind. When reaching the end of the runway, he encountered a severe downdraft, and descended into the trees near the end of the runway. Investigators from the Safety Board, Federal Aviation Administration, and Textron Aviation examined the wreckage on April 14, 2015, at the facilities of SP Aircraft, Boise, Idaho. The engine was later sent to Continental Motors Analytical Department, located in Mobile, Alabama. Airframe The main wreckage came to rest partially submerged in a creek, and had been subjected to severe thermal damage. The main wreckage consisted of the wings, empennage, engine, and the mostly ashen remains of the fuselage. The cabin was completely consumed by fire. The left wing remained affixed to the fuselage with the aileron and wing flap control surfaces still attached at their respective hinges. The wing tip, located about 35 ft upstream of the wreckage in the bush bordering the creek, was not attached, and had burned; pieces of the red navigation lens were found near the wingtip. The right wing remained affixed to the fuselage with the aileron and wing flap control surfaces still attached at their respective hinges. The inboard 3 ft of the wing had sustained thermal damage, and the remaining outboard area was not burned, consistent with it being partially submerged in the creek. The outboard half of the leading edge displayed crush deformation with the skin folded into itself giving an accordioned appearance with three distinct divots noted. The flap control surfaces were found in the retracted (flush) position. The actuator jackscrew was examined by measuring the exposed threads, which totaled 2.625 in. A representative from Textron Aviation stated that the position of the jackscrew was consistent to the flaps being extended between 5 and 10 degrees. Flap cable continuity was established from the control surface to the cockpit area. The aileron cable continuity was established from the control surfaces to the control yoke assembly. The rudder control surface remained affixed to the vertical fin structure. There were several areas of crush damage and punctures on the leading edge of the vertical fin. The rudder cables were attached to the rudder horn, and continuity was established to the aft baggage compartment through a series of pulleys and runs through lightning holes; the ends of the cables were thermally deteriorated. Investigators established continuity of the elevator control cables to the aft baggage compartment through a series of pulleys and runs through lightning holes; the ends of the cables were thermally deteriorated. The left inboard half of the horizontal stabilizer and elevator remained attached to the empennage. The outboard section was found about 450 ft upstream in the river. The outboard section of the horizontal stabilizer was deformed aft about 18 in from the leading edge creating an accordion appearance, with the aluminum skin folded over on itself and the boot surface flat. This u-shaped wrinkle was about 10 inches in diameter. There were several black rub markings and splatter found on the elevator control surface positioned aft of the divot. Fuel system continuity could not be established due to the amount of impact and thermal damage that the airplane had sustained. No fuel was present in either wing tank. The fuel selector valve was found in the "LEFT" position. Trace amounts of fuel were recovered from the fuel manifold and the gascolator. The nose landing gear (NLG) doors were located about 30 ft upstream from the main wreckage. The doors were fragmented, and sustained severe crush damage. The NLG wheel was separated at the strut, and found near the initial impact. A 2-inch portion of the rim's flange was fragmented on both sides of the wheel, each fracture being located in the same relative position on the left and right sides of the wheel rim. The right main landing gear was found in the wreckage. The gear was locked, and the tire/wheel assembly was attached and burned. The left main landing gear was found in the wreckage. The gear was unlocked, and the tire/wheel assembly was separated (the tire was found the furthest away from the debris field). According to the manufacture, Goodyear Aviation Tires, the left main landing gear, (p/n 606C86-6) had an outside diameter between 17.5 and 16.8 inches depending on the inflation. The section width was between 6.3 and 5.9 in. Engine The Continental Motors TSIO-520-R, serial number 294045-R, sustained impact damage. Investigators removed the upper spark plugs of all cylinders. According to the Champion Aviation Check-A-Plug AV-27 Chart, the spark plug signatures corresponded to normal engine operation although numerous plugs were coated with oil. A subsequent borescope examination revealed that the combustion chambers remained mechanically undamaged, and there was no evidence of foreign object ingestion (pre-impact) or detonation. The valves were intact and undamaged. There was no evidence of valve to piston face contact observed. Prior to the test run the Nos. 6 cylinder and several induction system components and exhaust risers were replaced due to impact-related damage. The engine was placed on a test bench at the manufacturer. The engine experienced a normal start on the first attempt without hesitation or stumbling in observed rpm. The engine rpm was advanced in steps for 5 minute intervals for warm-up in preparation for full power operation. The engine throttle was then advanced to full open position, and held for 5 minutes to stabilize. The engine throttle was rapidly advanced from idle to full throttle five times where it performed normally. Throughout the test phase, the engine accelerated normally without any hesitation, stumbling, or interruption in power, and demonstrated the ability to produce rated horsepower. The turbo controller was disassembled, and no anomalies were noted. The waste gate actuator was inspected, and determined to be at or near full extension, consistent with the waste gate being closed. The propeller remained attached to the engine crankshaft. All three blade tips remained attached. One blade was twisted to an opposite direction of rotation in the hub. The second blade was slight bowed on the outboard area. The third blade was bent forward at mid-span, and bent aft the outboard foot. The blades did not display any evidence of chordwise scratching or leading edge dents or dings. There was no evidence of mechanical malfunction or failure with the airframe or engine that would have precluded normal operation. Detailed examination reports with accompanying pictures are contained in the public docket for this accident. Global Positioning System (GPS) Data Investigators found a Garmin GPSMAP 496, battery-powered portable GPS receiver within the wreckage. The unit included a built-in Jeppesen database, and was capable of receiving XM satelli