# NTSB WPR15LA036: Champion 7AC, N84462, Darby, MT, November 7, 2014 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Limited investigation · Final report - Date: November 7, 2014, 09:00 local (16:00 UTC) - Place: Darby, MT - Coordinates: 45.978054, -114.154998 - Nearby events: https://openairdocs.org/map.md?lat=45.9781&lon=-114.1550&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Defining event: [Approach-VFR pattern final: Loss of control in flight](https://openairdocs.org/ntsb-events/240) - Highest injury: Serious injuries - Injuries: 2 serious - Status: Completed, report December 12, 2016 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: CMI, FAA - NTSB case key (mKey): 90370 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR15LA036 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/90370/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=90370 - Page: https://openairdocs.org/ntsb/WPR15LA036 ## Probable cause The pilot's failure to maintain airspeed while maneuvering in gusting wind conditions, which resulted in the airplane exceeding its critical angle of attack and experiencing an aerodynamic stall. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Champion 7AC, 4 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=21101MA), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Wind](https://openairdocs.org/ntsb-findings/03034000): Environmental issues › Conditions/weather/phenomena · Effect on operation (probable cause); cases with it: [Champion 7AC, 1 case](https://openairdocs.org/ntsb-findings/03034000/cases.md?model=21101MA), [All aircraft, 110 cases](https://openairdocs.org/ntsb-findings/03034000/cases.md) - [Performance/control parameters: airspeed](https://openairdocs.org/ntsb-findings/01062010): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Champion 7AC, 1 case](https://openairdocs.org/ntsb-findings/01062010/cases.md?model=21101MA), [All aircraft, 1,681 cases](https://openairdocs.org/ntsb-findings/01062010/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Approach-VFR pattern final: Aerodynamic stall/spin](https://openairdocs.org/ntsb-events/241); cases with it: [Champion 7AC, 1 case](https://openairdocs.org/ntsb-events/241/sequence.md?model=21101MA), [All aircraft, 1,529 cases](https://openairdocs.org/ntsb-events/241/sequence.md) - [Approach-VFR pattern final: Loss of control in flight](https://openairdocs.org/ntsb-events/240) (defining event); cases with it: [Champion 7AC, 2 cases](https://openairdocs.org/ntsb-events/240/sequence.md?model=21101MA), [All aircraft, 5,002 cases](https://openairdocs.org/ntsb-events/240/sequence.md) ## Analysis The commercial pilot reported that he was attempting to land the light sport airplane on a private grass airstrip surrounded by mountainous terrain. While maneuvering for landing, the airplane suddenly entered into a steep, right-wing-low bank. The wings then leveled momentarily before the airplane impacted the ground. The passenger in the rear seat of the airplane stated that he felt a downdraft or windshear just prior to impact. A post-accident examination of the airplane found no anomalies that would have precluded normal operation. The pilot reported the wind as light and variable with 5-10 knot gusts; however, he stated that during previous flights in the area, he experienced unexpected severe gusts and terrain-induced turbulence, followed by complete calm. The airplane was not equipped with a stall warning system or flaps. Since the airplane was maneuvering for landing approach at low airspeed, a sudden gust of wind or shift in wind speed or direction could have resulted in a rapid loss of airspeed, followed by an aerodynamic stall as the airplane reached its critical angle-of-attack. Due to the airplane's low altitude, the pilot likely did not have sufficient time to recover from the stalled condition prior to impacting terrain. ## Factual narrative On November 7, 2014, at 0900 mountain standard time, a Champion 7AC, N84462, impacted a farm field and wheeled sprinkler system, 10 miles south of Darby, Montana. The commercial pilot and single passenger were seriously injured, and the airplane was substantially damaged. The airplane was registered to the pilot and operated under the provisions of 14 Code of Federal Regulations, Part 91. Visual meteorological conditions prevailed for the personal flight, and no flight plan had been filed. According to the pilot he was attempting to land on a private grass airstrip in a farm field surrounded by mountainous terrain when the accident occurred. Witnesses observed the airplane descending at an estimated 90 degree right-wing-low bank angle; the wings then leveled before impacting the ground. The pilot stated that due to injuries he could not recall all the events leading up to the accident; however he recalled observing a TV interview of a witness after the accident, in which the witness stated that it was windy at the time of the accident. The nearest weather reporting station was 40 nautical miles north of the accident site and reported wind from 230 degrees at 4 knots. The pilot reported light and variable winds with 5-10 knot gusts at the time of the accident; however he stated that he has experienced unexpected severe gusts and terrain induced turbulence pass through the area momentarily followed by complete calm. The pilot rated passenger in the rear seat recalled that he felt what he believed to be wind shear or a down draft before impact. Post-accident examination of the airplane did not reveal any failures or malfunctions with the airplane that would have precluded normal operation. Further examination revealed that an undetermined amount of aviation fuel was recovered from the fuel system. It was also noted that the airplane was not equipped with flaps or a stall warning system. ## Aircraft - Registration: [N84462](https://openairdocs.org/deregistered/N84462-2018-03-07), registration cancelled 2018-03-07, S/N 7AC-3161, built 1946 (OpenAirDocs) - Reported make and model: CHAMPION 7AC - Registry model: [Champion 7AC](https://openairdocs.org/model/champion-7ac) (registry code 21101MA) (OpenAirDocs) - Registry engine: [Continental C85 series](https://openairdocs.org/engine/continental-c85-series) (registry code 17008, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 7AC-3161 - Year built: 1946 - Airframe hours: 7565 - Engines: Continental C85 85 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, March 20, 2014 - Departed: 4U7, CONNER, MT - Destination: Conner, MT - Equipment: None ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 60; injuries: serious; commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: sport pilot; last flight review March 21, 2014; seat: front; restraint: 3-point; flight hours: 1,750 total, 372 in this make and model, 1,750 as pilot in command, 11 in the last 90 days, 5 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 230° at 4 knots - Visibility: 10 statute miles - Lowest ceiling: 8,000 ft overcast - Temperature: 46 °F, dew point 36 °F - Altimeter: 30.32 inHg - Turbulence: Light - Observed at: KMSO, 40 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 20141107020169A](https://openairdocs.org/incident/20141107020169A), Nov 7, 2014: Champion 7AC, Darby, MT, Destroyed. On November 07, 2014 at approximately 09:07 mountain standard time (MST) the pilot of N84462 lost control of the aircraft while on approach to a grass airstrip… ## Docket (5 files) The files NTSB released with the investigation on October 7, 2016, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=90370. 10.1 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 8.9 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40445168&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Pilot Record of Conversation (item 2, .PDF, 109 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40445169&FileExtension=.PDF&FileName=Pilot%20Record%20of%20Conversation%20-Master.PDF - FAA Inspector Notes (item 3, .PDF, 105 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40445170&FileExtension=.PDF&FileName=FAA%20Inspector%20Notes%20-Master.PDF - Statement of Party Representatives to NTSB Investigation (item 4, .PDF, 56 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40445171&FileExtension=.PDF&FileName=Statement%20of%20Party%20Representatives%20to%20NTSB%20Investigation-Master.PDF - Accident Site Photos (item 5, .PDF, 865 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40445172&FileExtension=.PDF&FileName=Accident%20Site%20Photos%20-Master.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.