# NTSB ANC00FA024: Cessna U206G, N756HG, Iliamna, AK, February 5, 2000 - Type: NTSB accident investigation - Classification: Accident · Fatal · Field investigation · Final report - Date: February 5, 2000, 16:00 local (20:00 UTC) - Place: Iliamna, AK - Coordinates: 59.849208, -154.559249 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=59.8492&lon=-154.5592&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: Fatal - Injuries: 6 fatal - Status: Completed, report July 17, 2001 - Report: Approved by Office Director - NTSB office: Alaska Regional Office - NTSB case key (mKey): 48734 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC00FA024 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/48734/pdf - Page: https://openairdocs.org/ntsb/ANC00FA024 ## Probable cause The pilot's attempted flight into adverse weather, and his failure to maintain altitude/clearance above the snow-covered tundra. Factors associated with the accident were snow, rain, and whiteout conditions. ## Analysis The airplane impacted level terrain, covered by smooth, wind-blown, snow, in a left bank of 26 degrees or greater. The leading edge of the first impact crater was angled 15 degrees below the horizon. The area surrounding the wreckage for about one mile was featureless, snow-covered, tundra. Beyond one mile, were rising hills with areas of exposed vegetation. Visible and infrared satellite images displayed a band of bright cloud tops and thick clouds, which traversed the flight path of the accident airplane between the departure airport, 27 miles to the east, and the accident site. Similar reflective images existed over a weather reporting station with visibility of one mile in light snow and mist, and overcast ceilings of 1,100 feet. The airplane's heading at the time of impact was in the direction of the departure airport. The GPS receiver was providing navigation information to the original destination at the time of impact. The airplane was equipped with basic flight instruments, and the pilot was required by the company to demonstrate his ability to control the airplane by reference to those instruments. No evidence of any preimpact mechanical anomaly was discovered with the airplane. ## Factual narrative HISTORY OF FLIGHT On February 5, 2000, about 1600 Alaska standard time, a wheel equipped Cessna U206G airplane, N756HG, was destroyed when it collided with terrain, at 59 degrees, 44.17 minutes north latitude, 155 degrees, 56.23 minutes west longitude, approximately 27 miles west of Iliamna, Alaska. The commercial pilot and the five passengers on board were fatally injured. The flight was operated by Iliamna Air Taxi, Inc., of Iliamna, under 14 CFR, Part 135, as an on-demand air taxi flight. The flight departed from Iliamna at 1531 for Koliganek, Alaska. Visual meteorological conditions prevailed at both the origin and destination at the time of the accident, and a VFR flight plan was in effect. The flight was considered overdue by the company at 1755. A search was commenced by the company at 1815, and by the Alaska National Guard at 1835. Sunset in the area was about 1800. No emergency locator transmitter signal was received. The airplane was located at 1317 on February 6, in an area of level terrain, covered by about four feet of smooth, wind blown, snow. The terrain within about one mile of the wreckage site was without vegetation and featureless. Beyond one mile were rising hills, with areas of exposed vegetation. INJURIES TO PERSONS All six persons on board the airplane were fatally injured. DAMAGE TO AIRCRAFT The airplane was destroyed by impact forces. PERSONNEL INFORMATION The pilot held a U.S. commercial pilot certificate issued on July 19, 1988. His most recent U.S. second-class medical certificate was issued on April 9, 1999, with the requirement for corrective lenses. He held an airframe and powerplant mechanic certificate issued on March 31, 1987. The pilot was hired by Iliamna Air Taxi, Inc., on April 29, 1998, and worked as both a pilot and mechanic. He lived in Iliamna. He completed initial training, and was assigned to fly the Cessna 207, on June 30, 1998. On December 6, 1999, the pilot completed pilot-in-command checks in the Cessna 206. The pilot had about 50 hours experience in the Cessna 206 at the time of the accident. On each of the pilot's 14 CFR 135.293, and 135.299 Airman Competency / Proficiency Checks, it was noted that the pilot demonstrated "Basic Instrument Competency." In addition, each company Certificate of Flight Training included the following items: "(3) Flight under simulated instrument conditions," and "(8) Flight under simulated IFR conditions using each kind of navigational and approach facility used in normal operation." Flight and Duty Time On the day of the accident, the pilot's estimated total experience was 2,990 flight hours. In the 24 hours prior to the accident, the pilot had flown 5 hours. He completed his flights about 1100 on the day prior to the accident, and went home from work about 1700. He was off duty for 15 hours prior to reporting to work the morning of the accident. The pilot had flown 10.7 hours in the previous 7 days, and 54 hours in the previous 30 days. The pilot's normal workday during the winter months was from 0830 to 1700. He was also employed as a mechanic by the operator, and when not assigned flight duties, was assigned maintenance work. The pilot was described as physically active, and did not use tobacco or alcohol products. He was a salaried employee, not paid on the basis of completion of flights. AIRCRAFT INFORMATION The airplane was manufactured in 1978. It was equipped with a Teledyne Continental IO-520 engine, an external baggage pod mounted under the fuselage, and a Robertson Short Takeoff and Landing (STOL) kit. The airplane was configured to carry one pilot and five passengers at the time of the accident. The airplane was maintained on a 100-hour/annual inspection schedule. 88 hours had elapsed since the most recent 100 hour / annual inspection on June 23, 1999. A review of maintenance records revealed no preexisting anomalies at the time of the accident. The allowable maximum weight of the airplane was 3,600 pounds. The NTSB investigator-in-charge (IIC) estimated the total gross weight at the time of the accident to be 3,500 pounds. Required Equipment All equipment required by 14 CFR Part 91.205, 207, 209, and 135.149, 159, and 161, was installed on the accident airplane. The company was authorized to operate the airplane in day and night VFR conditions. 14 CFR Part 135.159, Equipment Requirements: Carrying Passengers Under VFR At Night, states, in part: "No person may operate an aircraft carrying passengers under VFR at night...unless it is equipped with- (a) A gyroscopic rate-of-turn indicator... (b) A slip skid indicator (c) A gyroscopic bank-and-pitch indicator. (d) A gyroscopic direction indicator..." METEOROLOGICAL INFORMATION The nearest official weather reporting station to the accident site is located at the Iliamna Airport. The terminal forecast for the Iliamna Airport called for 1,500 feet scattered, 3,500 feet overcast, and six miles visibility, with temporary conditions of three miles visibility in light rain and snow showers, and 1,500 feet overcast ceilings The weather observation at the Iliamna airport, at 1553, was ceiling 3,200 feet overcast, 10 miles visibility, temperature 38, dew point 32, winds 140 degrees at seven knots. The weather observation at the Iliamna airport, at 1653, was 3,400 feet overcast, 10 miles visibility, winds 180 degrees at five knots. The Area Forecast for the Bristol Bay area, valid until 0100 Alaska standard time, the evening of the accident was, in part: "scattered 1,500 feet, broken 4,500 feet, broken 8,000 feet. Occasional broken to overcast 1,500 feet, four miles visibility in light snow showers and light rain showers. Isolated ceilings below 1,000 feet, and visibility below three miles." An NTSB senior meteorologist received visible and infrared satellite data from the GOES-10 (Geostationary Operational Environmental Satellite-10) valid at 1545, and 1600, for the accident area. These visible and infrared images showed a band of bright cloud tops, and high levels of reflected solar energy (thick clouds), which extended north-northwestward from Kodiak Island, and traversed the flight path of the accident airplane between Iliamna and the accident site. At the same time as these observations, similar energy reflective images existed for the area of Dillingham, Alaska. Dillingham is approximately 96 miles west-southwest of the accident site. At 1552, the weather observation at Dillingham was: visibility one mile in light snow and mist, ceilings 1,100 feet overcast. The company Operation Specifications, paragraph A010, Aeronautical Weather Data, stated in part: "For VFR operations, the pilots own weather observations, or those of another competent observer may be used when approved sources are not available." Official sunset at the accident location was 1749. The end of evening civil twilight was 1835. AIDS TO NAVIGATION The airplane was equipped with a Bendix-King KLN-89B global position system (GPS) receiver, a Bendix-King KX-155 VHF Omnidirectional Range (VOR) receiver, and an Automatic Direction Finder (ADF) receiver. The KLN-89 GPS was tested at Bendix-King's facility in Olathe, Kansas, under the supervision of an FAA avionics inspector from the Kansas City, Missouri, Flight Standards District Office (FSDO). This inspection and data extraction revealed that the GPS was selected to navigate from the airplane's present position to Koliganek. The present position retained in nonvolatile memory in the KLN-89 is updated every 60 seconds. The present position of the airplane last recorded in nonvolatile memory was 59 degrees 44.17 minutes north latitude, 155 degrees 56.34 minutes west longitude. This position is less than 1/2 mile on a bearing of 245 degrees magnetic from the accident site. It could not be determined how many seconds (from one to 60) prior to t ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight encounter with weather, cruise - flight into adverse weather - attempted, pilot in command (cause) - weather condition - whiteout (contributing factor) - weather condition - snow (contributing factor) - weather condition - rain (contributing factor) - In flight collision with terrain/water, maneuvering - turn to reverse direction - terrain condition - tundra - terrain condition - snow covered (contributing factor) - altitude/clearance - not maintained, pilot in command (cause) ## Aircraft - Registration: [N756HG](https://openairdocs.org/deregistered/N756HG-2013-04-16), registration cancelled 2013-04-16, S/N U20604099, built 1978 (OpenAirDocs) - Reported make and model: Cessna U206G - Registry model: [Cessna U206G](https://openairdocs.org/model/cessna-u206g) (registry code 2073356) (OpenAirDocs) - Registry engine: [Continental IO-520 series](https://openairdocs.org/engine/continental-io-520-series) (registry code 17032, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: U20604099 - Airframe hours: 5455 - Engines: Continental IO-520-F56B 300 horsepower reciprocating - Damage: Destroyed - Flight: Part 135 - Registered owner: Iliamna Air Taxi, Inc. - Airworthiness certificate: Standard, Normal - Last inspection: Annual, July 5, 1999, 89 hours before - Departed: ILI, AK - Destination: JZZ, KOLIGANEK, AK - Flight plan: Company VFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 48; commercial; airplane ratings: single-engine land, single-engine sea; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; seat: left; toxicology performed; flight hours: 2,990 total, 50 in this make and model, 2,800 as pilot in command, 164 in the last 90 days, 54 in the last 30 days, 5 in the last 24 hours ## Weather - Conditions: Day - Wind: 140° at 7 knots - Visibility: 10 statute miles - Lowest ceiling: 3,200 ft overcast - Temperature: 37 °F - Altimeter: 29.00 inHg - Observed at: ILI, 27 nm away ## 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 20000205042079A](https://openairdocs.org/incident/20000205042079A), Feb 5, 2000: Cessna U206G, Iliamna, AK, Destroyed, 6 fatal. (-23) February 5, 2000, at 1550, a wheel equipped Cessna 206 airplane, N756HG, was destroyed when the airplane collided with remote, snow covered terrain, 30… ## Other investigations on N756HG (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 ANC98LA049](https://openairdocs.org/ntsb/ANC98LA049), May 17, 1998: Cessna U206G (N756HG), Iliamna, AK, substantial damage. Probable cause: The pilot's inadequate compensation for quartering tailwind conditions. A factor in the accident is the presence of a quartering tailwind. 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.