# NTSB WPR10CA469: Piper PA-18-150, N4036E, White Sulphur Springs, MT, September 24, 2010 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: September 24, 2010, 17:30 local (23:30 UTC) - Place: White Sulphur Springs, MT - Coordinates: 46.621112, -110.479446 - Nearby events: https://openairdocs.org/map.md?lat=46.6211&lon=-110.4794&mi=10 - Phase of flight: [Uncontrolled descent](https://openairdocs.org/ntsb-phases/650) (OpenAirDocs' grouping) - Defining event: [Uncontrolled descent: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report March 16, 2011 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 77396 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR10CA469 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/77396/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=77396 - Page: https://openairdocs.org/ntsb/WPR10CA469 ## Probable cause The pilot's failure to maintain control of the airplane during a go-around in turbulent wind conditions, which resulted in a collision with trees. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Turbulence](https://openairdocs.org/ntsb-findings/03032000): Environmental issues › Conditions/weather/phenomena · Effect on operation; cases with it: [Piper PA-18-150, 3 cases](https://openairdocs.org/ntsb-findings/03032000/cases.md?model=7101828), [All aircraft, 92 cases](https://openairdocs.org/ntsb-findings/03032000/cases.md) - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Piper PA-18-150, 160 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=7101828), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Object/animal/substance: tree(s)](https://openairdocs.org/ntsb-findings/03022020): Environmental issues › Physical environment · Not specified; cases with it: [Piper PA-18-150, 19 cases](https://openairdocs.org/ntsb-findings/03022020/cases.md?model=7101828), [All aircraft, 933 cases](https://openairdocs.org/ntsb-findings/03022020/cases.md) - [Performance/control parameters](https://openairdocs.org/ntsb-findings/01062000): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Piper PA-18-150, 14 cases](https://openairdocs.org/ntsb-findings/01062000/cases.md?model=7101828), [All aircraft, 1,269 cases](https://openairdocs.org/ntsb-findings/01062000/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Uncontrolled descent: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470) (defining event); cases with it: [Piper PA-18-150, 115 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=7101828), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) - [Approach-VFR go-around: Turbulence encounter](https://openairdocs.org/ntsb-events/360); cases with it: [Piper PA-18-150, 3 cases](https://openairdocs.org/ntsb-events/360/sequence.md?model=7101828), [All aircraft, 423 cases](https://openairdocs.org/ntsb-events/360/sequence.md) ## Analysis The pilot reported that he planned on landing his tailwheel-equipped airplane in an open field in front of a friend's mountain cabin. The pilot made his first approach to the landing area, dragging the airplane's wheels across the landing area to test the roughness of the terrain before landing. The pilot then initiated a go-around and planned on landing during the next pass. Immediately upon initiating the go-around, the pilot reported that he encountered severe turbulence over the tree-populated terrain outside the periphery of his landing area. The turbulence forced the airplane down through the trees and into the ground. The pilot egressed the cockpit and the airplane was consumed by a post-impact fire. The pilot stated that the airplane had no mechanical failures or malfunctions during the flight. ## Factual narrative The pilot reported that he planned on landing his single-engine, tail wheel equipped, airplane in an open field in front of a friend's mountain cabin. The pilot made his first approach to the landing area and "dragged" his wheels across the landing area to test the roughness of the terrain before landing. The pilot then initiated a go-around and planned on landing during the next pass. Immediately upon initiating the go-around the pilot reported that he encountered severe turbulence over the tree populated terrain outside the periphery of his landing area. The turbulence forced the airplane down through the trees and into the ground. The pilot egressed the cockpit and the airplane was consumed by a post impact fire. The pilot stated that the airplane and engine had no mechanical failures or malfunctions during the flight. ## Aircraft - Registration: [N4036E](https://openairdocs.org/aircraft/N4036E), registered now, S/N 18-7809042, built 1977 (OpenAirDocs) - Reported make and model: PIPER PA-18-150 - Registry model: [Piper PA-18-150](https://openairdocs.org/model/piper-pa-18-150) (registry code 7101828) (OpenAirDocs) - Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 18-7809042 - Airframe hours: 5380 - Engines: LYCOMING O-320 SERIES 180 horsepower reciprocating - Damage: Substantial damage - Fire: On-Ground - Flight: Personal, Part 91 - Operator: Gaston Gerald M - Registered owner: Gaston Gerald M - Airworthiness certificate: Standard, Normal - Last inspection: Annual, October 14, 2009 - Departed: KBZN, Bozeman, MT - Destination: White Sulphur Springs, MT ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 67; injuries: none; private; airplane ratings: single-engine sea, single-engine land; instrument ratings: airplane; medical: class 3; last flight review February 1, 2010; seat: front; flight hours: 5,900 total, 1,800 in this make and model, 35 in the last 90 days, 10 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 300° at 11 knots, gusting 20 - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 64 °F, dew point 34 °F - Altimeter: 30.20 inHg - Observed at: KHLN, 46 nm away ## Other investigations on N4036E (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 SEA99LA050](https://openairdocs.org/ntsb/SEA99LA050), Apr 10, 1999: Piper PA-18 (N4036E), Boulder, MT, substantial damage. Probable cause: The pilot-in-command's failure to maintain directional control after encountering a dust-devil during landing rollout, resulting in a ground loop and collapse of the main landing gear. Factors… ## Docket (1 files) The files NTSB released with the investigation on October 20, 2010, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=77396. 351 KB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 351 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40337835&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF 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.