# NTSB ANC93LA168: Cessna 170B, N2384D, Wulik River, AK, September 3, 1993 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: September 2, 1993, 22:30 local (Sep 3, 1993, 06:30 UTC) - Place: Wulik River, AK - Coordinates: 67.239112, -161.190261 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=67.2391&lon=-161.1903&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report June 30, 1994 - Report: Approved by Office Director - NTSB office: Alaska Regional Office - NTSB case key (mKey): 2422 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC93LA168 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/2422/pdf - Page: https://openairdocs.org/ntsb/ANC93LA168 ## Probable cause THE PILOT'S FAILURE TO MAINTAIN CONTROL OF THE AIRPLANE. A FACTOR WAS THE CROSSWIND. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of control - in flight, takeoff - aircraft control - not maintained, pilot in command (cause) - weather condition - crosswind (contributing factor) - In flight collision with terrain/water, takeoff ## Analysis THE PILOT SAID WHILE ATTEMPTING TO TAKEOFF FROM A MOUNTAIN RIDGE, THE LEFT MAIN WHEEL ENTERED A DEPRESSION AND HE HAD TO USE HARDER THAN NORMAL CONTROL FORCES TO KEEP THE AIRPLANE ALIGNED WITH THE TAKEOFF PATH. WHEN THE AIRPLANE CAME OUT OF THE DEPRESSION, IT BOUNCED INTO THE AIR AND BECAUSE OF THE LEFT QUARTERING HEADWIND, IT CAME BACK DOWN ON THE RIGHT MAIN WHEEL AND THE RIGHT WING. THE AIRPLANE THEN SPUN AROUND CLOCKWISE ABOUT 180 DEGREES AND HIT ON THE NOSE, THEN THE LEFT WING. BOTH MAIN LANDING GEAR BOXES WERE TORN OUT OF THE FUSELAGE, WHICH WAS ALSO DAMAGED. ## Factual narrative On September 2, 1993, at 2230 Alaska daylight time, the pilot of a wheel equipped Cessna 170 airplane, N2384D, lost control and dragged a wing while attempting to takeoff from a mountain ridge near the Wulik River, approximately 80 miles northwest of Kotzebue, Alaska. The airline transport pilot, the sole occupant, was not injured, and the airplane was substantially damaged. The personal flight, operating under 14 CFR Part 91, was destined for another remote landing area located about 1 mile away from the accident site. Visual meteorological conditions existed, and a VFR flight plan was filed. When the pilot was contacted by telephone on September 7, 1993, he stated the following, in part: "During the takeoff roll, the left main wheel got into a depression and I had to use harder than normal control forces to keep the airplane aligned with the takeoff path. When the airplane came out of the depression, it bounced into the air and because of the left quartering headwind, it came back down on the right main wheel and the right wing. The airplane then spun around clockwise about 180 degrees and hit on the nose, then the left wing. Both main landing gear boxes were torn out of the fuselage, which was also damaged." The pilot's statement on the accident report (NTSB Form 6120.1/2) varies considerably from his telephone statement on September 7, 1993. ## Aircraft - Registration: [N2384D](https://openairdocs.org/deregistered/N2384D-2012-09-06), registration cancelled 2012-09-06, S/N 20536, built 1976 (OpenAirDocs) - Reported make and model: CESSNA 170B - Registry model: [Cessna 170B](https://openairdocs.org/model/cessna-170b) (registry code 2072306) (OpenAirDocs) - Registry engine: [Continental C145 series](https://openairdocs.org/engine/continental-c145-series) (registry code 17012, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 20536 - Airframe hours: 2548 - Engines: CONTINENTAL O-300A 145 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Anderson, Thomas M. - Registered owner: Anderson, Thomas M. - Airworthiness certificate: Standard, Normal - Last inspection: Annual, March 20, 1993, 49 hours before - Flight plan: VFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 32; airline transport; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--w/ waivers/lim; seat: left; flight hours: 4,602 total, 140 in this make and model, 4,555 as pilot in command, 320 in the last 90 days, 120 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 360° at 20 knots, gusting 25 - Visibility: 50 statute miles - Lowest ceiling: none - Temperature: 36 °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 19930902052749A](https://openairdocs.org/incident/19930902052749A), Sep 2, 1993: Cessna 170B, Wulik River, AK, Substantial damage. (.4)The pilot said while attempting to takeoff from a mountain ridge, the left main wheel entered a depression and he had to use harder than normal control… 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.