# NTSB ANC02LA110: Cessna 185, N185CF, Port Alsworth, AK, September 1, 2002 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Limited investigation · Final report - Date: September 1, 2002, 09:00 local (17:00 UTC) - Place: Port Alsworth, AK - Coordinates: 60.111667, -154.671661 - Nearby events: https://openairdocs.org/map.md?lat=60.1117&lon=-154.6717&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: Serious injuries - Injuries: 3 serious - Status: Completed, report April 18, 2003 - Report: Approved by Office Director - NTSB office: Alaska Regional Office - Parties: FAA-AL-ANC FSDO 03 - NTSB case key (mKey): 55629 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC02LA110 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/55629/pdf - Page: https://openairdocs.org/ntsb/ANC02LA110 ## Probable cause The pilot's inadequate evaluation of the area weather conditions, and his subsequent inability to maintain terrain clearance upon encountering a downdraft, which resulted in an in-flight collision with tree-covered mountainous terrain. A factor in the accident was a downdraft. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight encounter with weather, cruise - weather condition - downdraft (contributing factor) - weather evaluation - inadequate, pilot in command (cause) - In flight collision with terrain/water, descent - uncontrolled - object - tree(s) - terrain condition - mountainous/hilly - altitude/clearance - not possible, pilot in command (cause) ## Analysis The private certificated pilot departed a remote lake in a float-equipped airplane, en route to another lake. The route of flight crossed a mountain saddle about 5 miles from the point of departure. After takeoff, the pilot reported that he gained sufficient altitude to clear the mountain saddle. The pilot said that as he crossed the saddle, the airplane encountered a violent downdraft that unexpectedly resulted in a loss of several hundred feet of altitude. He said he was unable to arrest the airplane's descent, and maneuvered the airplane to avoid a low hill. The airplane collided with tree-covered terrain on the side of the mountain, and then nosed over. The pilot indicated he did not obtain a weather briefing. He reported that the weather conditions included unlimited visibility, a temperature of 50 degrees F, a wind of 3 to 5 knots from the north, no precipitation, no turbulence, and little to no wind at the departure point. The area forecast indicated no significant turbulence. The closest official weather observation station was 14 miles away, and a METAR was reporting in part: Wind, calm; visibility, 20 statute miles in light rain; clouds and sky condition, 3,000 feet broken, 5,500 feet overcast; altimeter, 29.91 inHg. ## Factual narrative On September 1, 2002, about 0900 Alaska daylight time, a float-equipped Cessna 185 airplane, N185CF, sustained substantial damage during a collision with tree-covered terrain, about 14 miles southwest of Port Alsworth, Alaska. The airplane was being operated as a Title 14, CFR Part 91, visual flight rules (VFR) local area personal flight when the accident occurred. The airplane was operated by the pilot. The private certificated pilot, and the two passengers, received serious injuries. Visual meteorological conditions prevailed. The flight originated from Keyes Point, Lake Clark, Alaska, located about 5 miles southeast of the accident site, at 0850, and was en route to Long Lake. No flight plan was filed. During an interview with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC), on September 1, the pilot reported that he just departed Lake Clark, and had leveled the airplane about 1,000 feet above the ground. As the airplane crossed over a small ridge, the pilot said he encountered a severe downdraft. The airplane began to descend, and he banked the airplane to the left to avoid a low hill. He applied full engine power, but the airplane continued to descend. The pilot said he could not maintain altitude, and the airplane collided with the ground and nosed over. In the Pilot/Operator Aircraft Accident/Incident Report (NTSB Form 6120.1) submitted by the pilot, the pilot indicated he did not obtain a weather briefing. He reported that the weather conditions included unlimited visibility, a temperature of 50 degrees F, a wind of 3 to 5 knots from the north, no precipitation, and no turbulence. In the narrative portion of the report, the pilot indicated that there was little to no wind at the departure point. After takeoff, he gained sufficient altitude to clear a mountain saddle along the route of flight. He stated that the airplane suddenly encountered a violent downdraft that unexpectedly caused the airplane to lose several hundred feet of altitude. He was unable to arrest the airplane's descent, and the airplane collided with a tree on the side of the mountain and nosed over. The area forecast for Bristol Bay, issued on September 1, 2002, at 0545, and valid until 1800, stated, in part: Clouds and weather; AIRMET for mountain obscuration, Alaska Range occasionally obscured in clouds and precipitation, improving. Clouds, 2,500 feet scattered, 4,000 feet broken, 6,000 feet broken, tops at 8,000 feet, scattered conditions in light rain showers. Coast/offshore, occasionally 2,500 feet broken. Outlook, valid from 1800 to 1200 on September 2, 2002, coast/offshore, marginal VFR conditions with ceilings due to mist; inland, VFR conditions. Turbulence, none significant. Icing and freezing level, none significant, freezing level, 5,000 feet. The closest official weather observation station is Port Alsworth, Alaska. At 0848, an Aviation Routine Weather Report (METAR) was reporting in part: Wind, calm; visibility, 20 statute miles in light rain; clouds and sky condition, 3,000 feet broken, 5,500 feet overcast; altimeter, 29.91 inHg. ## Aircraft - Registration: [N185CF](https://openairdocs.org/deregistered/N185CF-2013-07-02), registration cancelled 2013-07-02, S/N 185-02676 (OpenAirDocs) - Reported make and model: Cessna 185 - Registry model: [Cessna 185F](https://openairdocs.org/model/cessna-185f) (registry code 2072820) (OpenAirDocs) - Category: Airplane - Serial number: 02676 - Airframe hours: 2599 - Engines: CONTINENTAL IO-520-D 300 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: David Renkoski - Airworthiness certificate: Standard, Normal - Last inspection: Annual, June 15, 2002, 40 hours before - Departed: PORT ALSWORTH, AK ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 43; injuries: serious; private; airplane ratings: single-engine sea, single-engine land; medical: class 3, valid medical--no waivers/lim.; last flight review July 21, 1999; seat: left; flight hours: 1,559 total, 150 in this make and model, 1,459 as pilot in command, 15 in the last 90 days, 7 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 20 statute miles - Lowest ceiling: 3,000 ft broken - Temperature: 48 °F - Altimeter: 29.90 inHg - Observed at: PALJ, 14 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 20020901025869A](https://openairdocs.org/incident/20020901025869A), Sep 1, 2002: Cessna 185F, Portalsworth, AK, Substantial damage. (-23) On 9/01/2002 about 0900 adt, a float-equipped Cessna 185 airplane, N185CF, sustained damage during a collision with terrain, about 14 miles southeast of… 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.