# NTSB ANC00FA052: Piper PA-18, N3935Z, Kotzebue, AK, May 1, 2000 - Type: NTSB accident investigation - Classification: Accident · Fatal · Field investigation · Final report - Date: May 1, 2000, 06:30 local (14:30 UTC) - Place: Kotzebue, AK - Coordinates: 67.240913, -161.190734 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=67.2409&lon=-161.1907&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: Fatal - Injuries: 1 fatal - Status: Completed, report July 10, 2001 - Report: Approved by Office Director - NTSB office: Alaska Regional Office - NTSB case key (mKey): 49106 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC00FA052 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/49106/pdf - Page: https://openairdocs.org/ntsb/ANC00FA052 ## Probable cause The pilot's continued VFR flight into instrument meteorological conditions, and his failure to maintain control of the airplane due to spatial disorientation. Factors in the accident were weather conditions consisting of low ceilings, fog, a whiteout, and the pilot's lack of certification. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of control - in flight, cruise - weather condition - low ceiling (contributing factor) - lack of certification, pilot in command (contributing factor) - vfr flight into imc - continued, pilot in command (cause) - spatial disorientation, pilot in command (cause) - weather condition - fog (contributing factor) - aircraft control - not maintained, pilot in command (cause) - weather condition - whiteout (contributing factor) - In flight collision with terrain/water, descent - uncontrolled - terrain condition - snow covered ## Analysis The pilot, the holder of an expired student pilot certificate, departed a remote village with a load of whale meat. The route of flight was along the coast of the Bering Sea, over snow-covered terrain, adjacent to snow-covered sea ice. The weather conditions along the route consisted of low ceilings with areas of fog and snow showers. The pilot did not file a flight plan. He was not reported overdue, and no ELT signal was received from the airplane. The wreckage was discovered by passing villagers about 3/4 mile inland from the coastline. The airplane collided with terrain and came to rest inverted. No preimpact mechanical malfunction was discovered. According to relatives, the pilot, who was not an aviation mechanic, maintained the airplane himself, and no maintenance records were located. ## Factual narrative HISTORY OF FLIGHT On May 1, 2000, about 0630 Alaska daylight time, a ski-equipped Piper PA-18 airplane, N3935Z, collided with snow-covered terrain 33.5 miles west-northwest of Kotzebue, Alaska, at latitude 67 degrees, 13.29 minutes north and longitude 163 degrees, 43.43 minutes west. The airplane was being operated as a visual flight rules (VFR) cross-country personal flight when the accident occurred. The airplane was operated by the pilot. The pilot, the sole occupant and holder of an expired student pilot certificate, received fatal injuries. Instrument meteorological conditions prevailed in the area of the accident. The flight originated from Kivalina, Alaska, about 0500. The pilot departed Kotzebue in the accident airplane on April 30, 2000, at 1502. According to personnel at the Federal Aviation Administration (FAA) Flight Service Station (FSS) at Kotzebue, the pilot did not obtain a weather briefing from the facility, nor did he file a flight plan. On May 1, 2000, about 1900, the Alaska State Trooper's office in Kotzebue was notified that the accident airplane was discovered by passing villagers traveling on snowmachines along the coast near Cape Krusentern. The airplane was found inverted about 3/4 mile east of the coastline. In conversations with family members, the Troopers learned that the pilot flew to Kivalina the day before the accident. On May 1, the pilot departed Kivalina with a load of whale meat. The pilot had not filed a flight plan for the return flight to Kotzebue, and had not been reported overdue. On the evening of May 1, Alaska State Trooper personnel responded to the accident scene and recovered the pilot from the wreckage. PERSONNEL INFORMATION The pilot held a student pilot/third class medical certificate that was issued on October 21, 1997. The medical certificate contained the limitation that the pilot must wear corrective lenses. A student pilot certificate is valid for 24 months. No personal flight records were located for the pilot. The aeronautical experience listed on page 3 of this report was based on estimates provided by relatives. Review of records on file in the Federal Aviation Administration (FAA) Airman and Medical Records Center located in Oklahoma City, revealed that on the pilot's application for medical certificate, dated October 21, 1997, the pilot indicated that his total aeronautical experience consisted of "none." AIRCRAFT INFORMATION The airplane airframe and engine maintenance records were not located. A relative of the pilot stated that the pilot, who was not an aviation mechanic, performed the maintenance on the airplane. The relative said an inspection of the engine had recently been completed by the pilot. At the accident scene, the recording hour meter in the RPM gauge indicated 5,095.13 hours. METEOROLOGICAL INFORMATION The closest official weather observation station is Kotzebue. On May 1, 2000, at 0553, an Aviation Routine Weather Report (METAR) at Kotzebue was reporting, in part: Wind, 290 degrees (true) at 8 knots; visibility, 2 statute miles in mist; clouds and sky condition, 100 feet overcast; temperature, 15 degrees F; dew point, 12 degrees F; altimeter, 29.63 inHg. At 0602, a METAR at Kotzebue was reporting in part: Wind, 280 degrees (true) at 6 knots; visibility, 5 statute miles in mist; clouds and sky condition, 100 feet overcast; temperature, 15 degrees F; dew point, 12 degrees F; altimeter, 29.63 inHg. An automated surface observation system (ASOS) is located at Kivalina, 37 miles northwest of the accident site. At 0453, the ASOS was reporting, in part: Wind, 090 degrees (true) at 3 knots; visibility, 10 miles; clouds and sky condition, clear; temperature, minus 2 degrees F; dew point, minus 6 degrees F; altimeter, 29.59 inHg. At 0540, the ASOS at Kivalina was reporting, in part: Wind calm; visibility, 10 miles; clouds and sky condition, 300 feet scattered; temperature, minus 4 degrees F; dew point, minus 7 degrees F; altimeter, 29.59 inHg. The weather conditions reported to the Trooper's office by villagers in the area of the accident included low ceilings, fog, and scattered snow showers. COMMUNICATIONS No radio communications were received from the pilot on the day of the accident. No emergency transmitter locator (ELT) signal was received from the accident airplane. WRECKAGE AND IMPACT INFORMATION Following the recovery of the pilot by Alaska State Trooper personnel on May 1, 2000, the accident scene was visited by relatives and friends of the pilot. They removed the pilot's personal equipment, about 300 pounds of whale meat, the propeller, and the airplane's ELT. The propeller was located and examined outside a relative's home in Kotzebue on May 2, 2000, by an Alaska State Trooper, the National Transportation Safety Board (NTSB) investigator-in-charge (IIC), and an FAA airworthiness inspector. The examination revealed that the bolts utilized to attach the propeller to the engine crankshaft flange were sheared at the aft side of the propeller. The sheared bolts had slight necking of their normal diameter at the point of separation. The edges of three bolt holes on the rear of the propeller had curling and gouging of a portion of their diameter. The propeller blades were each curled aft, about two feet inboard from the tip. The blades had trailing edge gouging, torsional twisting, slight spanwise scratching near each tip, and slight "S" bending. The tip of one blade was fractured. Frozen snow/ice and tundra debris was adhering to the fractured end. According to the Trooper, the propeller was found at the accident site, 165 feet from the initial point of impact. The Alaska State Trooper, the NTSB IIC, and the FAA inspector then traveled to the accident scene and examined the airplane wreckage. 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 070 degrees. (All heading/bearings noted in this report are oriented toward magnetic north.) The first observed point of ground contact was a near vertical, wedge shaped disruption of the snow, about 6 six inches deep, and about three feet long. The right wing position light bulb lens was located at that initial point of contact. About 30 feet further along the wreckage path, a shallow depression was found in the snow. About 55 feet from the initial point of ground contact, a circular disruption of the snow and tundra was found. In the area of soil disruption, small pieces of paint chips, and small pieces of broken plexiglass were found. Larger pieces of broken plexiglass and soil were scattered along the wreckage path to the airplane's point of rest. The airplane came to rest inverted about 270 feet from the initial point of ground contact. All of the airplane's major components were found at the main wreckage area. The fuselage was bent and buckled about 15 degrees to the right along the airplane's longitudinal axis, just aft of the rear cabin area. The tail of the airplane was pointed in the direction of travel along the wreckage path. The empennage was undamaged. The upper portion of the trailing end of the left ski was fractured about 12 inches aft of the axle. The right ski was bent slightly upward, aft of the axle, and had impact damage at the tip. The upper portion of the cockpit area, including the wing spar carry-through, was crushed and broken in an aft and downward direction. The right wing was fractured at the inboard end, and was found in a near vertical, leading edge down position. The underside of the wing had 45 degree diagonal wrinkling of the wing surface that was evident from mid-span of the leading edge, to the inboard, trailing edge of the wing. The right wing lift struts were buckled about mid-span, and were attached at their respective ends to the wing and fuselage. The outboard third of the w ## Aircraft - Registration: [N3935Z](https://openairdocs.org/deregistered/N3935Z-2017-03-10), registration cancelled 2017-03-10, S/N 18-7781, built 1962 (OpenAirDocs) - Reported make and model: Piper PA-18 - Registry model: [Piper PA-18-150](https://openairdocs.org/model/piper-pa-18-150) (registry code 7101828) (OpenAirDocs) - Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 18-7781 - Airframe hours: 5095 - Engines: Lycoming O-320-B2B 160 horsepower reciprocating - Damage: Destroyed - Flight: Personal, Part 91 - Registered owner: Gordon W. Ito - Airworthiness certificate: Standard, Normal - Departed: KVL, KIVALINA, AK - Destination: PAOT, KOTZEBUE, AK ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 37; student; medical: class 3, expired; seat: front; toxicology performed; flight hours: 600 total ## Weather - Conditions: Instrument (IMC), Day - Visibility: 5 statute miles - Lowest ceiling: 100 ft overcast - Temperature: 16 °F ## 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 20000501009409A](https://openairdocs.org/incident/20000501009409A), May 1, 2000: Piper PA18150, Cape Krusenster, AK, No damage, 1 fatal. (-23) Aircraft rt wing contacted the tundra app. 40 miles north north west of otz. May 1, 2000, at 0530 hrs enroute to otz from kiualina whale camp. Aircraft… ## Other investigations on N3935Z (1) 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. - [NTSB ANC86LA036](https://openairdocs.org/ntsb/ANC86LA036), Mar 20, 1986: Piper PA-18 (N3935Z), Kotzebue, AK, substantial damage 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.