ANC08FA087

The pilot's failure to maintain adequate airspeed during maneuvering flight, which resulted in an aerodynamic stall and uncontrolled descent to the ground. Contributing to the accident was the airplane's overgross weight condition.

The pilot departed on a local personal flight in an amphibious, float-equipped experimental airplane with two passengers. About 40 minutes after takeoff, the burning wreckage of the airplane was spotted by overflying aircraft. The airplane was built by the pilot from a kit, and was designed by the kit manufacturer to have two side-by-side seats in the cockpit. A large cargo area was behind the two front seats. According to a neighbor, the accident airplane was equipped with a third seat, designed and built by the pilot. The third seat was installed in the cargo area and was designed to fold up for use, and was equipped with a seat belt. The only passenger access to the third seat would have been from the cockpit. The kit manufacturer indicated that several builders have designed and built a third seat in the cargo compartment area of their respective airplanes. These seats had been individually designed, as there were no after-market or third-party suppliers of rear seats for the airplane. No maintenance records or construction build records were located for the airplane. No weight and balance data for the airplane was located. According to the manufacturer, the airplane's gross weight was 2,100 pounds if equipped with floats. A calculation of the airplane's estimated weight done by the Safety Board's Investigator-In-Charge, came to an estimated 2,110 pounds without any inclusion of fuel, which indicated that the airplane was overgross at the time of the accident. The airplane appeared to have collided with the ground in a left-wing- and nose-low attitude, an indication of an aerodynamic stall. The airplane was destroyed by a postcrash fire. No preimpact mechanical malfunctions were found during an examination of the wreckage. An examination of data from a GPS receiver found at the crash site revealed that just prior to the accident the airplane was in a descending left turn, having lost 273 feet in the last 6 seconds before impact.

HISTORY OF FLIGHT On July 12, 2008, about 1100 Alaska daylight time, an amphibious float-equipped kit built experimental Iversen Glastar SH-4 airplane, N212DR, was destroyed by impact and postimpact fire when it collided with terrain, about 35 miles west of Kenai, Alaska. The airplane was being operated as a visual flight rules (VFR) local area personal flight under Title 14, CFR Part 91, when the accident occurred. The airplane was operated by the pilot. The private certificated pilot, and the two passengers, received fatal injuries. Visual meteorological conditions prevailed in the area of the accident. The flight originated at a private airstrip near Kenai about 1030, and no flight plan was filed. Federal Aviation Administration (FAA) personnel notified the National Transportation Safety Board (NTSB) investigator-in-charge (IIC) that burning wreckage of an airplane was spotted by over-flying aircraft about 1110. Search and rescue personnel responded to the scene, as well as Alaska State Troopers from Soldotna, Alaska. The Alaska State Troopers reported that the pilot maintained a summer residence near Kenai, and the passengers were acquaintances from out-of-state. PERSONNEL INFORMATION Pilot Information The pilot held a private pilot certificate with airplane single-engine land, single-engine sea, and instrument airplane ratings. In addition, he held a repairman certificate for the accident airplane. His most recent second-class medical certificate was issued on March 21, 2008, and contained the limitation that he must have available glasses for near vision. No personal flight records were located for the pilot, and the aeronautical experience listed on page 3 of this report was obtained from Federal Aviation Administration (FAA) airmen records on file in the Airman and Medical Records Center in Oklahoma City. On the pilot's application for medical certificate, dated March 21, 2008, the pilot indicated that his total aeronautical experience was about 2,710 hours, of which 40 were in the previous 6 months. AIRCRAFT INFORMATION The airplane was built by the pilot from a kit, and was issued an FAA experimental airworthiness certificate with experimental limitations on June 26, 1997. The airplane had an aluminum tube frame that formed the structure from the firewall to the aft end of the baggage area. The frame was covered by fiberglass composite that formed the fuselage and vertical stabilizer. The wings, rudder, and horizontal stabilizer were all metal. The pilot installed a 180 horsepower engine. The airplane kit was designed by the manufacturer with two side-by-side seats in the cockpit. A large cargo area was behind the two front seats, with a weight limitation of 250 pounds. When the pilot applied for an airworthiness certificate in 1997, the application noted that the airplane was equipped with 2 seats. According to a neighbor who maintained a hangar next to the pilot, and who was also building a Glastar airplane, the accident airplane was equipped with a third seat, designed and built by the pilot. The third seat was installed in the cargo area, and was designed to fold up for use, and was equipped with a seat belt. Access to the cargo area could be gained via a side compartment door on the left side of the fuselage, but it would not have been large enough for use by a passenger. The only passenger access to the third seat would have been from the cockpit. The kit manufacturer indicated that several builders of Glastar airplanes have designed and built a third seat in the cargo compartment area of their respective airplanes. These seats had been individually designed, as there were no after market or third party suppliers of rear seats for the airplane. No maintenance records or construction build records were located for the airplane. No weight and balance data for the airplane was located. The pilot's neighbor reported that the airplane received an annual inspection in June, 2008. According to the Alaska State Troopers, the pilot's weight was 170 pounds. The front seat passenger weighed 185 pounds, and the rear seat passenger weighed 255 pounds. The airplane was equipped with 2200 series amphibious floats from the Montana Float Company. The average empty weight for an airplane on floats was estimated by the float manufacturer as about 1,500 pounds. According to the manufacturer of the kit, the airplane's gross weight was 2,100 pounds if equipped with floats. The NTSB IIC calculated the airplane's gross weight at the time of the accident as approximately 2,110 pounds, without including any weight for fuel. METEOROLOGICAL INFORMATION The closest weather reporting facility was Big River Lakes, Alaska, which was about 9 miles south-southwest of the accident site. At 1050, an aviation routine weather report (METAR) was reporting, in part: Wind, calm; visibility, 40 statute miles; clouds and sky condition, 6,000 feet overcast; temperature, 55 degrees F; dew point, 51 degrees F; altimeter, 30.10 inHg. COMMUNICATIONS There were no reports of communication with the accident airplane. WRECKAGE AND IMPACT INFORMATION The National Transportation Safety Board IIC, and an FAA inspector from the Anchorage Flight Standards District Office, Anchorage, Alaska, examined the wreckage at the accident site on July 15. A path of wreckage debris and ground scars from the first observed point of ground contact to the wreckage point of rest was on a magnetic heading of 120 degrees. (All heading/bearings noted in this report are oriented using magnetic north.) The first disruption of the ground was found about 60 feet from the wreckage point of rest. A second and larger disruption of the ground was found about 30 feet beyond the first impact point. The second area of disruption was about 6 feet in diameter, and contained portions of broken Plexiglas. The airplane came to rest to the left of the two impact points, with the nose of the airplane pivoted to the left, oriented on a 340 degree heading. All of the airplane's major components were found at the main wreckage area. The airplane came to rest in an upright position, with the left wing displaced slightly forward of its normal orientation to the fuselage, and was lying over the left float. The aileron and flap remained attached to the wing, and the left flap appeared to be drooped about 10 to 15 degrees. The leading edge of the left wing was crushed and flattened in an aft direction, from about midspan to the wingtip. The inboard end of the wing, and the inboard fuel tank, was consumed by fire. The outboard fuel tank contained a small amount of fuel. The right wing was displaced aft about 45 degrees from its normal orientation to the fuselage. The inboard portion of the right wing was resting on top of the aft portion of the fuselage. The aileron and flap remained attached to the wing, and the right flap appeared to be up. The lead edge at the outboard end of the wing was flattened and crushed aft, with upward curling of the wingtip. The inboard end of the wing was fire damaged, but the inboard fuel tank was intact and contained fuel. The outboard fuel tank contained a small amount of fuel. The vertical stabilizer, rudder, and horizontal stabilizer had minor damage, and the empennage was displaced slightly to the right of the main cockpit/cabin area. The elevator trim tab was displaced slightly downward. The entire cockpit, baggage area, and fuselage to the vertical stabilizer, was incinerated by a postcrash fire. Both wing lift struts remained attached to their respective wing and fuselage attach points. The wheel portion of the amphibious floats were the "up" position. The left float was broken from its fuselage attach points, and was to the left and parallel to the fuselage. The nose of the left float assembly was bent upward, about 90 degrees, and damaged by fire. The aft end of the left float was damaged by fire. The right