# NTSB GAA20CA075: Cessna 182, N97596, Broomfield, CO, November 6, 2019 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: November 6, 2019, 14:00 local (21:00 UTC) - Place: Broomfield, CO - Coordinates: 39.908889, -105.117225 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=39.9089&lon=-105.1172&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing: Aerodynamic stall/spin](https://openairdocs.org/ntsb-events/241) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report May 21, 2020 - Report: Approved by Office Director - NTSB office: General Aviation Accidents - Parties: FAA - NTSB case key (mKey): 100565 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=GAA20CA075 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/100565/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=100565 - Page: https://openairdocs.org/ntsb/GAA20CA075 ## Probable cause The pilot’s inadvertent flight into icing conditions, which resulted in the accumulation of structural icing and 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: [Cessna 182Q, 34 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=2072732), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Object/animal/substance: snow/ice](https://openairdocs.org/ntsb-findings/03022060): Environmental issues › Physical environment · Effect on equipment (probable cause); cases with it: [Cessna 182Q, 1 case](https://openairdocs.org/ntsb-findings/03022060/cases.md?model=2072732), [All aircraft, 67 cases](https://openairdocs.org/ntsb-findings/03022060/cases.md) - [Temp/humidity/pressure: conducive to structural icing](https://openairdocs.org/ntsb-findings/03031025): Environmental issues › Conditions/weather/phenomena · Effect on operation (probable cause); cases with it: [Cessna 182Q, 1 case](https://openairdocs.org/ntsb-findings/03031025/cases.md?model=2072732), [All aircraft, 103 cases](https://openairdocs.org/ntsb-findings/03031025/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute: Other weather encounter](https://openairdocs.org/ntsb-events/400); cases with it: [Cessna 182Q, 6 cases](https://openairdocs.org/ntsb-events/400/sequence.md?model=2072732), [All aircraft, 1,127 cases](https://openairdocs.org/ntsb-events/400/sequence.md) - [Enroute: Structural icing](https://openairdocs.org/ntsb-events/210); cases with it: [Cessna 182Q, 1 case](https://openairdocs.org/ntsb-events/210/sequence.md?model=2072732), [All aircraft, 102 cases](https://openairdocs.org/ntsb-events/210/sequence.md) - [Landing: Aerodynamic stall/spin](https://openairdocs.org/ntsb-events/241) (defining event); cases with it: [Cessna 182Q, 5 cases](https://openairdocs.org/ntsb-events/241/sequence.md?model=2072732), [All aircraft, 1,529 cases](https://openairdocs.org/ntsb-events/241/sequence.md) - [Landing: Hard landing](https://openairdocs.org/ntsb-events/092); cases with it: [Cessna 182Q, 15 cases](https://openairdocs.org/ntsb-events/092/sequence.md?model=2072732), [All aircraft, 2,102 cases](https://openairdocs.org/ntsb-events/092/sequence.md) ## Analysis The pilot reported that, while operating in instrument meteorological conditions, the airplane started accumulating ice on the wings and windshield. He informed air traffic control (ATC) and requested to be diverted. ATC vectored him to a nearby airport for an instrument approach. Following completion of the instrument approach, while the airplane was about 10 ft above ground level, the airplane stalled and then landed hard on the runway. The pilot taxied the airplane to the ramp without further incident. The airplane sustained substantial damage to the fuselage. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation. The Federal Aviation Administration's Pilot's Handbook of Aeronautical Knowledge, FAA-H-8083-25B, provides information and guidance in a section titled, "Stalls," which stated, in part, that "as little as 0.8 millimeter of ice on the upper wing surface increases drag and reduces aircraft lift by 25 percent." ## Factual narrative The pilot reported that, while in instrument meteorological conditions (IMC) the airplane started accumulating ice on the wings and windshield. He informed air traffic control (ATC) and requested to be diverted. ATC vectored him to a nearby airport for an instrument approach. Following completion of the instrument approach, while the airplane was about 10 ft above the runway, the airplane stalled and landed hard on the runway. The pilot taxied to the ramp without further incident. The airplane sustained substantial damage to the fuselage. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation. The Federal Aviation Administration's Pilot's Handbook of Aeronautical Knowledge, FAA-H-8083-25B, provides information and guidance in a section titled "Stalls" which stated in part: As little as 0.8 millimeter of ice on the upper wing surface increases drag and reduces aircraft lift by 25 percent. ## Aircraft - Registration: [N97596](https://openairdocs.org/aircraft/N97596), registered now, S/N 18267143, built 1979 (OpenAirDocs) - Reported make and model: Cessna 182 (Q) - Registry model: [Cessna 182Q](https://openairdocs.org/model/cessna-182q) (registry code 2072732) (OpenAirDocs) - Registry engine: [Continental O-470 series](https://openairdocs.org/engine/continental-o-470-series) (registry code 17026, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 18267143 - Year built: 1979 - Airframe hours: 6470.4 - Engines: Continental O-470 230 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Aero-Sphere Inc - Registered owner: Aero-Sphere Inc - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, August 22, 2019 - Departed: APA, Denver, CO - Destination: LMO, Longmont, CO - Flight plan: IFR - Airport: BJC, Rocky Mountain Metropolitan, runway 30R, 9,000 × 100 ft, asphalt - Equipment: Onboard weather, Electronic multifunction display, ADS-B, Stall warning system ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 32; injuries: none; commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 1, with waivers/limitations; last flight review July 31, 2018; seat: left; restraint: 3-point; flight hours: 430 total, 82 in this make and model ## Weather - Conditions: Day - Wind: 80° at 6 knots - Visibility: 10 statute miles - Lowest ceiling: 700 ft overcast - Temperature: 32 °F, dew point 30 °F - Altimeter: 30.29 inHg - Icing: Unknown - Turbulence: Unknown - Observed at: KBJC, 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 20191106020699A](https://openairdocs.org/incident/20191106020699A), Nov 6, 2019: Cessna 182Q, Broomfield, CO, Substantial damage. On November 6, 2019 at approximately 0936 MST, N97596, a Cessna model 182Q aircraft was substantially damaged during an attempt to land at Rocky Mountain… ## Docket (3 files) The files NTSB released with the investigation on January 10, 2020, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=100565. 1.1 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 827 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40479558&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Record of Phone Conversation (Pilot) (item 2, .PDF, 97 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40479559&FileExtension=.PDF&FileName=Record%20of%20Phone%20Conversation%20(Pilot)-Master.PDF - Damage Photos (item 3, .PDF, 184 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40479560&FileExtension=.PDF&FileName=Damage%20Photos-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.