# NTSB ANC02FA097: Piper PA-18, N4065Z, Skwentna, AK, August 14, 2002 - Type: NTSB accident investigation - Classification: Accident · Fatal · Field investigation · Final report - Date: August 14, 2002, 15:39 local (23:39 UTC) - Place: Skwentna, AK - Coordinates: 61.95, -151.166671 - Nearby events: https://openairdocs.org/map.md?lat=61.9500&lon=-151.1667&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Highest injury: Fatal - Injuries: 2 fatal - Status: Completed, report August 26, 2003 - Report: Approved by Office Director - NTSB office: Alaska Regional Office - Parties: Federal Aviation Administration, Alaska State Troopers / Dept. of Public Safety - NTSB case key (mKey): 55529 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC02FA097 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/55529/pdf - Page: https://openairdocs.org/ntsb/ANC02FA097 ## Probable cause The pilot's failure to maintain adequate airspeed while on approach to land, which resulted in an inadvertent stall, and subsequent collision with trees. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of control - in flight, approach - vfr pattern - base leg/base to final - use of inappropriate medication/drug, pilot in command - airspeed - inadequate, pilot in command (cause) - stall - inadvertent, pilot in command (cause) - In flight collision with object, descent - uncontrolled - object - tree(s) ## Analysis The private pilot departed in a wheel-equipped airplane with one passenger on a cross-country flight en route to a remote airstrip. Family members reported that the pilot was en route to the family's remote cabin located adjacent to the destination airstrip, with an anticipated return 3 days later. When the airplane did not return, the flight was reported overdue. Search personnel checked the pilot's cabin and reported that there were no signs that anyone had been at the cabin recently. A review of the accident pilot's flight plan for the outbound portion of the flight revealed that the pilot cancelled his flight plan while still airborne, over the destination airport. Ground search personnel and aerial search personnel located the airplane wreckage along the anticipated final approach path to the destination airstrip. The accident site consisted of thick-forested terrain, with trees extending upwards of 30 feet. The airplane wreckage was not easily visible due to thick vegetation. The fuselage came to rest in an inverted and nose down attitude. A postaccident examination of the airplane did not reveal any mechanical malfunctions. No emergency locator transmitter (ELT) signal was received from the airplane. The ELT was found detached from its mounting tray, with the antenna lead still connected, and the switch in the ARM position. The ELT was sent to the manufacturer for disassembly and testing under supervision of the FAA. The test revealed that the G-switch, and all other components in the ELT, operated within the prescribed parameters. A review of recorded data obtained from the pilot's hand held GPS unit revealed that the airplane approached the destination airstrip from the southeast, and entered a right downwind approach for runway 27. The airplane then proceeded southeast bound, past the approach end of runway 27, and made a gradual turn, consistent with a right base leg for landing on runway 27. As the right turn progressed, the rate of turn increased sharply. The last GPS track recorded indicated a magnetic heading of 095 degrees. An autopsy of the pilot concluded he did not die immediately upon impact, but did not establish a time of death. Toxicological testing found very low levels of tetrahydrocannabinol in the pilot's blood. ## Factual narrative HISTORY OF FLIGHT On August 14, 2002, about 1539 Alaska daylight time, a wheel-equipped Piper PA-18 airplane, N4065Z, was destroyed during an in-flight collision with tree-covered terrain, about 1,500 feet west of the Skwentna Airport, Skwentna, Alaska. The airplane was being operated as a visual flight rules (VFR) cross-country personal flight when the accident occurred. The certificated private pilot, and the one passenger, received fatal injuries. Visual meteorological conditions prevailed, and a VFR flight plan was filed. The flight originated about 1445, from the Lake Hood Airstrip, Anchorage, Alaska, and was en route to Skwentna. A family member reported that the pilot intended to fly to his remote cabin located near Skwentna on August 14, and return by 0800 on August 16. When the airplane did not arrive in Anchorage, the family member reported the airplane overdue on August 16, about 1722. At the request of the family, friends in Skwentna checked the pilot's cabin, and reported that there were no signs that anyone had been at the cabin recently. A review of the accident pilot's flight plan for the outbound portion of the flight on August 14, revealed that the pilot cancelled his flight plan at 1533, while still airborne, over the destination airport of Skwentna. On August 16, about 2118, ground search personnel in Skwentna, aided by aerial search personnel, located the airplane wreckage along the anticipated final approach path to runway 27, at Skwentna. During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC) on August 23, a resident of Skwentna who was familiar with the accident airplane, reported seeing the accident airplane on August 16, between 1530 and 1545, as it approached from the south-southeast. He said that when he noticed the airplane, he was working next to the Skwentna River, located about 1 mile south of the Skwentna airport. He added that he would routinely see the accident airplane in the area during the summer months. The witness reported that when he noticed the airplane, it seemed to be "flying very slow...slower than normal." The witness could not recall if the accident airplane's wing flaps were extended, or retracted. He added that once the airplane had passed by, he did not see or hear anything unusual, and was unaware that the airplane had crashed. PERSONNEL INFORMATION The pilot held a private pilot certificate with an airplane single-engine land rating. The most recent second-class medical certificate was issued to the pilot on April 10, 2002, and contained the limitation that the holder must wear corrective lenses. No personal flight records were located for the pilot. On the pilot's application for medical certificate, dated April 10, 2002, the pilot indicated that his total aeronautical experience consisted of about 300 hours, of which 25 hours were accrued in the previous 6 months. AIRCRAFT INFORMATION No airframe or engine records were located for the accident airplane. METEOROLOGICAL INFORMATION The closest official weather observation station is located at the Skwentna Airport, in Skwentna. On August 14, 2002, at 1450, an automated weather observation system was reporting, in part: Wind, 290 degrees (true) at 7 knots; visibility, 35 statute miles; clouds, 5000 feet few, 15,000 feet scattered; temperature, 54 degrees F; dew point, 39 degrees F; altimeter, 29.78 inHg. COMMUNICATIONS On August 14, at 0757, the pilot contacted the preflight eight position of the Kenai, Alaska, Automated Flight Service Station (AFSS), and obtained a weather briefing for the flight from the Lake Hood Airstrip en route to Skwentna. The AFSS specialist provided the pilot with a standard weather briefing for the anticipated route of flight. At the conclusion of the weather briefing, the pilot filed a VFR flight plan, with an anticipated activation time of 1100. The pilot noted that his anticipated flight time to Skwentna would be one hour en route, with four hours of fuel, and two souls on board. At 1221, the pilot contacted the preflight six position of the Kenai AFSS, and requested that his departure time be amended to 1330. The AFSS specialist amended the proposed takeoff to show 1330, and asked the pilot if he would like any weather briefing updates. The pilot declined any further weather updates, and stated: "No, I'll get that ah I'll get that later." At 1451, after departing from the Lake Hood Airstrip, the pilot contacted the in-flight one position of the Kenai AFSS, and requested that his previously filed VFR flight plan be activated. The AFSS specialist confirmed that the flight plan was activated. At 1532, the pilot contacted the in-flight one position of the Kenai AFSS, and said: "Cub six five zulu, we're five miles from Skwentna, request the uh latest Skwentna weather." The AFSS specialist on duty responded by saying: "Cub six five zulu, Kenai radio, Skwentna wind two niner zero, at seven knots, visibility three five, few clouds at five thousand, one five thousand scattered, temperature one niner, dew point six, altimeter three zero three eight, and no specials. Anything else sir we can do for you, over?" The pilot responded by saying: "Cub six five zulu, no thanks, that's fine, if you could cancel my VFR flight, appreciate it." At 1533, the AFSS specialist responded to the pilot's request by saying: "Cub six five zulu, flight plan closed." The accident pilot's last radio transmission was: "Cub six five zulu, roger." A complete transcript of all preflight telephone and air to ground communications is included in the public docket for this accident. WRECKAGE AND IMPACT INFORMATION The NTSB IIC, a Federal Aviation Administration (FAA) operations inspector, and an Alaska State Trooper, examined the airplane wreckage at the accident site on August 17, 2002. The location of the airplane wreckage was within the city limits of Skwentna, about 50 feet north of a roadway used by residents of Skwentna. The airplane wreckage was not visible from the road due to thick vegetation. The accident site consisted of thick-forested terrain, with trees extending upwards of 30 feet. The forest floor had numerous large fallen tree trunks and limbs, and soft, tundra-covered ground. The entire wreckage was found in a small opening in the trees, with all of the airplane's major components located at the main wreckage area. Examination of the trees surrounding the scene revealed two broken tree tops. Vertical scrape marks were visible on tree bark next to the site. A large tree adjacent to where the wreckage came to rest had extensive gash and chop marks, consistent with propeller slash marks. The fuselage came to rest in an inverted and nose down attitude, with the nose of the airplane oriented on a 100 degree heading. (All headings/bearings noted in this report are oriented toward magnetic north.) The fuselage was extensively twisted and buckled. The top portion of the engine and propeller were buried in the soft, tundra-covered terrain. The cockpit area and instrument panel were crushed aft. The floor of the cabin was buckled upward, and the cabin roof area was buckled inward. The left wing was inverted and torn free at the fuselage to wing attach points, and was displaced aft about 6 feet. It was buckled in a "U" shape, about mid-span, and draped around a tree, measuring about 12 inches in diameter. The left wing flap and aileron remained attached to the wing. The left fuel tank was ruptured. The right wing remained attached to the fuselage, but sustained extensive leading edge aft crushing. The right wing flap and aileron remained attached to the wing. The empennage was inverted. The rudder remained attached to the vertical stabilizer, and each had minor damage. The elevator remained attached to the horizontal stabilize ## Aircraft - Registration: N4065Z (not matched to a registry record) - Reported make and model: Piper PA-18 - Category: Airplane - Serial number: 18-8075 - Engines: Lycoming O-320 150 horsepower reciprocating - Damage: Destroyed - Flight: Personal, Part 91 - Registered owner: Daniel T. Schenkenberger - Airworthiness certificate: Standard, Normal - Departed: Z41, Anchorage, AK - Destination: SKW, Skwentna, AK - Flight plan: VFR - Airport: SKW, Skwentna, runway 27, 3,400 × 75 ft, gravel ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 43; injuries: fatal; private; airplane ratings: single-engine land; medical: class 3, valid medical--w/ waivers/lim; seat: front; toxicology performed; flight hours: 300 total, 25 in the last 90 days ## Weather - Conditions: Visual (VMC), Day - Wind: 290° at 7 knots - Visibility: 35 statute miles - Temperature: 66 °F, dew point 43 °F - Altimeter: 29.78 inHg - Observed at: SKW ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 20020814020049A](https://openairdocs.org/incident/20020814020049A), Aug 14, 2002: Piper PA18150, Skwentna, AK, No damage, 2 fatal. (-23) The pilot and his passenger departed lake hood airport (lhd), anchorage, Alaska, on August 14, 2002, enroute to Skwentna Airport (skw), Skwentna, Alaska.… From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.