# NTSB WPR12LA231: Cessna 172G, N4640L, Silver City, ID, May 27, 2012 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: May 26, 2012, 21:50 local (May 27, 2012, 03:50 UTC) - Place: Silver City, ID - Coordinates: 42.99361, -116.66333 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=42.9936&lon=-116.6633&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering: Aerodynamic stall/spin](https://openairdocs.org/ntsb-events/241) - Highest injury: Minor injuries - Injuries: 3 minor - Status: Completed, report September 5, 2013 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: FAA FSDO - NTSB case key (mKey): 83760 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR12LA231 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/83760/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=83760 - Page: https://openairdocs.org/ntsb/WPR12LA231 ## Probable cause The pilot‘s failure to maintain airspeed while maneuvering in mountainous terrain with reduced visibility, which resulted in an aerodynamic stall. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Use of equip/info](https://openairdocs.org/ntsb-findings/02063000): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Cessna 172G, 1 case](https://openairdocs.org/ntsb-findings/02063000/cases.md?model=2072420), [All aircraft, 111 cases](https://openairdocs.org/ntsb-findings/02063000/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: [Cessna 172G, 3 cases](https://openairdocs.org/ntsb-findings/01062010/cases.md?model=2072420), [All aircraft, 1,681 cases](https://openairdocs.org/ntsb-findings/01062010/cases.md) - [Ceiling/visibility/precip: low visibility](https://openairdocs.org/ntsb-findings/03035015): Environmental issues › Conditions/weather/phenomena · Effect on operation; cases with it: [Cessna 172G, 2 cases](https://openairdocs.org/ntsb-findings/03035015/cases.md?model=2072420), [All aircraft, 175 cases](https://openairdocs.org/ntsb-findings/03035015/cases.md) - [Terrain: mountainous/hilly terrain](https://openairdocs.org/ntsb-findings/03021010): Environmental issues › Physical environment · Effect on operation; cases with it: [Cessna 172G, 2 cases](https://openairdocs.org/ntsb-findings/03021010/cases.md?model=2072420), [All aircraft, 329 cases](https://openairdocs.org/ntsb-findings/03021010/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Maneuvering: Aerodynamic stall/spin](https://openairdocs.org/ntsb-events/241) (defining event); cases with it: [Cessna 172G, 4 cases](https://openairdocs.org/ntsb-events/241/sequence.md?model=2072420), [All aircraft, 1,529 cases](https://openairdocs.org/ntsb-events/241/sequence.md) - [Maneuvering: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Cessna 172G, 21 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=2072420), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The pilot stated that he was maneuvering over mountainous terrain in deteriorating weather conditions and reduced visibility when the airplane stalled. He pushed the nose down to recover from the aerodynamic stall and then abruptly pitched the nose up to avoid oncoming rising terrain. The airplane subsequently impacted trees and settled to the ground. The pilot reported no preimpact mechanical malfunctions or failures that would have precluded normal operation. ## Factual narrative On May 26, 2012, about 2150 mountain daylight time, a Cessna 172G, N4640L, collided with mountainous terrain while maneuvering about five miles southeast of Silver City, Idaho. The private pilot and two passengers received minor injuries. The airplane sustained substantial damage to the fuselage, wings and flight control surfaces. The airplane was registered to the pilot, and operated as a personal flight under the provisions of 14 Code of Federal Regulations Part 91. Marginal visual meteorological conditions prevailed and dusk light prevailed. No flight plan was filed for the cross-county flight. The flight originated from Rome, Oregon (REO), about 1930. The pilot’s intended destination was Mountain Home, Idaho (U76). The pilot reported that the accident flight was the third flight leg of the day. Earlier in the day he flew with his passengers from Lodi, California, to Susanville, California. About 1400 the pilot departed Susanville with a planned destination of Mountain Home, Idaho. About 1 hour after departing Susanville, the pilot “turned back” due to deteriorating weather conditions and diverted to Rome, Oregon. The pilot landed in Rome uneventfully. Initially, the pilot and passengers planned to overnight in Rome; however, weather conditions improved and the pilot again departed for Mountain Home. As the flight progressed over mountainous terrain (Owyhee Mountains) weather conditions deteriorated and the pilot encountered reduced flight visibility, broken clouds and precipitation; a passenger reported the flight visibility dropped to “zero.” While maneuvering over a ridgeline and nearby weather, the pilot stated the airplane "stalled." He pushed the nose down to “break” the aerodynamic stall and then pitched up abruptly to match approaching rising terrain. The airplane subsequently impacted trees and settled to the ground. Initial rescue efforts were delayed due to snow showers and poor visibility. On May 28, search and rescue personnel reached the accident site and airlifted the pilot and passengers to a regional medical facility in Boise, Idaho. The pilot reported no preaccident mechanical malfunctions or failures with the airplane that would have precluded normal operation. ## Aircraft - Registration: [N4640L](https://openairdocs.org/deregistered/N4640L-2018-02-07), registration cancelled 2018-02-07, S/N 17254635, built 1966 (OpenAirDocs) - Reported make and model: CESSNA 172G - Registry model: [Cessna 172G](https://openairdocs.org/model/cessna-172g) (registry code 2072420) (OpenAirDocs) - Registry engine: [Continental 0-300 series](https://openairdocs.org/engine/continental-0-300-series) (registry code 17022, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 17254635 - Airframe hours: 3589 - Engines: CONT MOTOR O-300 SER 145 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Brown, Brian - Registered owner: Brown Jayann - Airworthiness certificate: Standard, Utility; Standard, Normal - Last inspection: Annual, November 4, 2011 - Departed: KREO, Rome, OR - Destination: U76, Mountain Home, ID ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 47; injuries: minor; private; airplane ratings: single-engine land; medical: class 3, without waivers/limitations; seat: left; flight hours: 402 total, 308 in this make and model, 400 as pilot in command ## Weather - Conditions: Visual (VMC), Dusk - Visibility: 20 statute miles ## 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 20120526008899A](https://openairdocs.org/incident/20120526008899A), May 26, 2012: Cessna 172G, Silver City, ID, Substantial damage. On may 26, 2010, about 2150 mountain daylight time, a Cessna 172G, N4640L, collided withmountainous terrain while maneuvering about five miles southeast of… ## Docket (3 files) The files NTSB released with the investigation on June 25, 2013, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=83760. 369 KB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 140 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40370495&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Passenger Record of Conversation (item 2, .PDF, 110 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40395562&FileExtension=.PDF&FileName=Passenger%20Record%20of%20Conversation-Master.PDF - Photo 1: Overview Accident Airplane (item 3, .PDF, 119 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40395579&FileExtension=.PDF&FileName=Photo%201%3A%20Overview%20Accident%20Airplane-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.