# NTSB WPR20CA183: Cessna 310, N87395, Butte, MT, June 15, 2020 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 4 · Data collection · Final report - Date: June 15, 2020, 12:30 local (18:30 UTC) - Place: Butte, MT - Coordinates: 45.954723, -112.497497 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=45.9547&lon=-112.4975&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing: Landing gear collapse](https://openairdocs.org/ntsb-events/094) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed - Report: Approved by Office Director - Investigation class: Class 4 - Basic report with no Prelim publish - NTSB office: Western Pacific Region - Parties: FAA - NTSB case key (mKey): 101452 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR20CA183 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/101452/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=101452 - Page: https://openairdocs.org/ntsb/WPR20CA183 ## Probable cause The pilot's failure to maintain clearance from a fence post during final approach which resulted in a damage to the left main landing gear, and its subsequent collapse during landing. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Attention/monitoring: monitoring environment](https://openairdocs.org/ntsb-findings/02021545): Personnel issues › Psychological · Pilot (probable cause); cases with it: [Cessna 310R, 1 case](https://openairdocs.org/ntsb-findings/02021545/cases.md?model=2074245), [All aircraft, 809 cases](https://openairdocs.org/ntsb-findings/02021545/cases.md) - [Performance/control parameters: descent/approach/glide path](https://openairdocs.org/ntsb-findings/01062040): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Cessna 310R, 3 cases](https://openairdocs.org/ntsb-findings/01062040/cases.md?model=2074245), [All aircraft, 809 cases](https://openairdocs.org/ntsb-findings/01062040/cases.md) - [Object/animal/substance: pole](https://openairdocs.org/ntsb-findings/03022010): Environmental issues › Physical environment · Effect on operation (probable cause); cases with it: [Cessna 310R, 1 case](https://openairdocs.org/ntsb-findings/03022010/cases.md?model=2074245), [All aircraft, 142 cases](https://openairdocs.org/ntsb-findings/03022010/cases.md) - [Landing gear system: main landing gear](https://openairdocs.org/ntsb-findings/01023210): Aircraft › Aircraft systems · Damaged/degraded; cases with it: [Cessna 310R, 1 case](https://openairdocs.org/ntsb-findings/01023210/cases.md?model=2074245), [All aircraft, 241 cases](https://openairdocs.org/ntsb-findings/01023210/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Landing: Landing gear collapse](https://openairdocs.org/ntsb-events/094) (defining event); cases with it: [Cessna 310R, 8 cases](https://openairdocs.org/ntsb-events/094/sequence.md?model=2074245), [All aircraft, 1,787 cases](https://openairdocs.org/ntsb-events/094/sequence.md) - [Landing: Runway excursion](https://openairdocs.org/ntsb-events/300); cases with it: [Cessna 310R, 3 cases](https://openairdocs.org/ntsb-events/300/sequence.md?model=2074245), [All aircraft, 3,643 cases](https://openairdocs.org/ntsb-events/300/sequence.md) - [Landing: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Cessna 310R, 10 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=2074245), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis While on final approach to land, about 150 ft above the ground, the pilot maneuvered and descended the airplane away from a bird. The pilot then realized that he was on a lower approach path to the runway after he observed an airport perimeter fence, but felt that he could still perform a safe landing and increased engine power to continue the approach. The airplane’s left main landing gear then struck a fence post and the pilot initiated a go-around to return to the departure airport. After unsuccessful attempts to verify the left main landing gear was extended and locked, he initiated a landing with full flaps and in a right-wing low attitude. As the airplane touched down, the left main landing gear collapsed, the airplane veered left, exited the runway, and the left wing struck a runway sign. The airplane sustained substantial damage to the left wing. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation. ## Aircraft - Registration: [N87395](https://openairdocs.org/deregistered/N87395-2022-03-05), registration cancelled 2022-03-05, S/N 310R0543, built 1975 (OpenAirDocs) - Reported make and model: Cessna 310 (R) - Registry model: [Cessna 310R](https://openairdocs.org/model/cessna-310r) (registry code 2074245) (OpenAirDocs) - Registry engine: [Continental IO-520 series](https://openairdocs.org/engine/continental-io-520-series) (registry code 17032, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 310R0543 - Year built: 1975 - Engines: Continental IO 520 SERIES 285 horsepower reciprocating; Continental IO 520 SERIES 285 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Angle Of Attack Aeronautics LLC - Registered owner: Angle Of Attack Aeronautics LLC - Airworthiness certificate: Standard, Normal - Departed: 7S1, Twin Bridges, MT - Destination: BTM, Butte, MT - Flight plan: Unknown - Airport: BTM, Bert Mooney, runway 33, 9,000 × 150 ft, asphalt - Equipment: Unknown ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 62; injuries: none; flight instructor, commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 2, with waivers/limitations; seat: left ## Weather - Conditions: Visual (VMC), Day - Wind: variable at 4 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 55 °F, dew point 27 °F - Altimeter: 30.02 inHg - Observed at: KBTM, 1 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 20200615006189A](https://openairdocs.org/incident/20200615006189A), Jun 15, 2020: Cessna 310R, Butte, MT, Substantial damage. Pilot was on approach to twin bridges airport when a hawk flew into his flight path. The pilot maneuvered and the aircraft struck a fence that was about 800'… ## Docket (3 files) The files NTSB released with the investigation on September 10, 2020, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=101452. 360 KB in all. - Record of Conversation-Pilot (item 1, .PDF, 98 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40486842&FileExtension=.PDF&FileName=Record%20of%20Conversation-Pilot-Master.PDF - Pilot Statement (item 2, .PDF, 128 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40486843&FileExtension=.PDF&FileName=Pilot%20Statement-Master.PDF - Accident Photo (item 3, .PDF, 134 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40486844&FileExtension=.PDF&FileName=Accident%20Photo-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.