# NTSB ANC01LA112: Arctic S-1B2, N61AT, Wrangell, AK, August 11, 2001 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: August 11, 2001, 13:15 local (21:15 UTC) - Place: Wrangell, AK - Coordinates: 56.769443, -132.053329 - Nearby events: https://openairdocs.org/map.md?lat=56.7694&lon=-132.0533&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report February 20, 2002 - Report: Approved by Office Director - NTSB office: Alaska Regional Office - Parties: FAA-AL-JNU FSDO 05 - NTSB case key (mKey): 53032 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC01LA112 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/53032/pdf - Page: https://openairdocs.org/ntsb/ANC01LA112 ## Probable cause The pilot's inadequate evaluation of the weather conditions during a downwind landing at a remote lake. Factors in the accident were a downdraft, rough/uneven terrain, and the pilot's inadequate in-flight planning/decision(s). ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight encounter with weather, approach - vfr pattern - final approach - weather evaluation - inadequate, pilot in command (cause) - weather condition - downdraft (contributing factor) - in-flight planning/decision - inadequate, pilot in command (contributing factor) - In flight collision with terrain/water, approach - vfr pattern - final approach - terrain condition - rough/uneven (contributing factor) ## Analysis The private certificated pilot was landing at a remote lake in a float-equipped airplane. The pilot reported he was landing toward the south because it was the only suitable approach path into the lake. The wind was blowing from the north at 15 knots. During the landing approach, the pilot said he encountered a downdraft, and the airplane began to descend below the planned approach path. The pilot turned the airplane into the wind, but he said he was unable to out-climb the downdraft. The airplane then collided with trees and rocks, and received damage to wings, fuselage, and engine. ## Factual narrative On August 11, 2001, about 1315 Alaska daylight time, a float-equipped Arctic Aircraft Company Inc., S-1B2 airplane, N61AT, sustained substantial damage while landing at a remote lake, about 21 miles north of Wrangell, Alaska. 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 private certificated pilot, and the sole passenger, were not injured. Visual meteorological conditions prevailed. A VFR flight plan was filed from Petersburg, Alaska, to Alpine Lake, to Petersburg. The flight originated at the Lloyd Roundtree Seaplane Facility, Petersburg, about 1245. During a telephone conversation with a National Transportation Safety Board (NTSB) investigator, on August 13, the pilot reported that he was landing toward the south at the lake. He said the approach toward the south is the only suitable approach path into the lake, and the wind was blowing from the north at 15 knots. When the airplane was on final approach, it encountered a downdraft, and began to descend below the planned approach path. The pilot turned the airplane into the wind, but he said he was unable to out-climb the downdraft. The airplane then collided with trees and rocks, and received damage to wings, fuselage, and engine. ## Aircraft - Registration: [N61AT](https://openairdocs.org/aircraft/N61AT), registered now, S/N 1012, built 1979 (OpenAirDocs) - Reported make and model: ARCTIC AIRCRAFT CO. INC. S-1B2 - Registry model: [Arctic S-1B2](https://openairdocs.org/model/arctic-s-1b2) (registry code 0790208) (OpenAirDocs) - Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 1012 - Airframe hours: 1857 - Engines: LYCOMING O-320-B2B 160 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: David W. Cushing - Airworthiness certificate: Standard, Normal - Last inspection: Annual, December 7, 2000, 45 hours before - Departed: 63A, PETERSBURG, AK - Destination: WRANGELL, AK - Flight plan: VFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 52; injuries: none; private; airplane ratings: single-engine sea, single-engine land; medical: class 1, valid medical--w/ waivers/lim; last flight review July 27, 2001; seat: front; flight hours: 801 total, 124 in this make and model, 800 as pilot in command, 17 in the last 90 days, 12 in the last 30 days, 0 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 325° at 15 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 61 °F - Altimeter: 30.13 inHg ## Other investigations on N61AT (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 ANC01LA072](https://openairdocs.org/ntsb/ANC01LA072), Jun 24, 2001: Arctic S-1B2 (N61AT), Petersburg, AK, substantial damage. Probable cause: The pilot's selection of an unsuitable landing area. A factor associated with the accident was soft terrain. 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.