# NTSB SEA02LA169: Cessna 172, N6830A, W. Yellowstone, MT, August 31, 2002 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: August 31, 2002, 11:30 local (17:30 UTC) - Place: W. Yellowstone, MT - Coordinates: 44.691665, -111.118331 - Nearby events: https://openairdocs.org/map.md?lat=44.6917&lon=-111.1183&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report April 18, 2003 - Report: Approved by Office Director - Parties: FAA-FSDO - NTSB case key (mKey): 55618 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA02LA169 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/55618/pdf - Page: https://openairdocs.org/ntsb/SEA02LA169 ## Probable cause The pilot's compensation for the wind conditions was inadequate during the landing roll. A quartering tailwind was a factor. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of control - on ground/water, landing - roll - compensation for wind conditions - inadequate, pilot in command (cause) - weather condition - tailwind (contributing factor) - On ground/water encounter with terrain/water, landing - roll - terrain condition - rough/uneven ## Analysis The pilot reported that after the aircraft touched on runway 19, he needed to apply left rudder input, followed by left braking action to counteract the weathervane effect. The pilot stated that despite the increased inputs, the airplane departed the runway centerline and traveled off the side of the runway. The left main landing gear separated at the gear leg attachment and the left wing contacted the surface. Shortly after the accident, the winds were reported from 300 degrees at 8 knots. Post accident inspection of the gear leg, gear leg attach bolt, gear box and brake indicated a side load. No anomalies were reported for the brake system. ## Factual narrative On August 31, 2002, about 1130 mountain daylight time, a tail wheel equipped Cessna 172, N6830A, registered to I Fly Strand Aviation and operated by a private pilot as a 14 CFR Part 91 personal flight, was substantially damaged during the landing roll at Yellowstone Airport, West Yellowstone, Montana. Visual meteorological conditions prevailed at the time and no flight plan was filed. The private pilot and his passenger were not injured. The flight departed from Bozeman, Montana, about 45 minutes prior to the accident. During a telephone interview and subsequent written statement, the pilot reported that the fixed base operator on the airport was reporting the winds as favoring runway 01, with winds out of the west at 10 knots. The pilot reported that aircraft were also landing on runway 19, so he flew over the runway to determine the wind direction. The wind sock on the approach end of 19 looked okay, however, the wind sock at mid-field indicated a wind from the west. The pilot chose to set-up for a landing on runway 19. The pilot stated that after the airplane touched down, he needed to apply left rudder input, followed by left braking action to "counteract the somewhat weak weathervane effect." The pilot reported that despite the increased inputs, the airplane departed the runway centerline and traveled off the side of the runway. The left main landing gear separated at the gear leg attachment and the left wing contacted the surface. The airplane pivoted and came to rest almost 90 degrees to the runway heading. At 1146, Yellowstone Airport weather facility was reporting winds from 300 degrees at 8 knots. The airplane was moved to Beegles Aircraft Service, Greeley, Colorado. An Air Safety Investigator with the National Transportation Safety Board and an Air Safety Investigator from Cessna Aircraft Company inspected the left main gear leg, left gear leg attach bolt, the left gear leg box and left gear brake. The investigators reported that it appeared that the left main gear experienced a side load and that the left gear leg attach bolt was bent. No anomalies were reported for the brake system. The outer tire rim rubber was scuffed and the outer wheel hub was damaged. ## Aircraft - Registration: [N6830A](https://openairdocs.org/aircraft/N6830A), registered now, S/N 28930, built 1956 (OpenAirDocs) - Reported make and model: Cessna 172 - Registry model: [Cessna 172](https://openairdocs.org/model/cessna-172) (registry code 2072402) (OpenAirDocs) - Registry engine: [Continental 0-300 series](https://openairdocs.org/engine/continental-0-300-series) (registry code 17022, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 28930 - Airframe hours: 2216 - Engines: Lycoming O-360-A4M 180 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Christian Locher - Registered owner: I Fly Strand Aviation - Airworthiness certificate: Standard, Normal - Last inspection: Annual, January 31, 2002, 158 hours before - Departed: BZN, Bozeman, MT - Destination: WYS, W. Yellowstone, MT - Airport: WYS, Yellowstone, runway 19, 8,399 × 150 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 45; injuries: none; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; last flight review May 5, 2002; seat: left; flight hours: 1,917 total, 129 in this make and model, 1,809 as pilot in command, 107 in the last 90 days, 47 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 300° at 8 knots - Visibility: 20 statute miles - Temperature: 66 °F - Altimeter: 30.26 inHg - Observed at: WYS ## 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 20020831023399A](https://openairdocs.org/incident/20020831023399A), Aug 31, 2002: Cessna 172, West Yellowston, MT, Substantial damage. (-23) Pilot states he was landing in gusty winds got hit by a cross wind and when he went to correct using brakes the left brake failed. ## Other investigations on N6830A (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 DEN01LA051](https://openairdocs.org/ntsb/DEN01LA051), Jan 31, 2001: Cessna 172 (N6830A), Grand Junction, CO, substantial damage. Probable cause: Failure by the pilot to maintain directional control of the aircraft during landing roll. A factor was lack of total pilot experience in aircraft make and model. 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.