# NTSB ERA16CA246: Mooney M20, N3877H, Clifton, TN, June 18, 2016 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: June 18, 2016, 13:28 local (18:28 UTC) - Place: Clifton, TN - Coordinates: 35.42361, -85.730834 - Nearby events: https://openairdocs.org/map.md?lat=35.4236&lon=-85.7308&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute-change of cruise level: Loss of control in flight](https://openairdocs.org/ntsb-events/240) - Highest injury: No injuries - Injuries: 4 uninjured - Status: Completed, report September 7, 2017 - Report: Approved by Office Director - NTSB office: Eastern Region Aviation - Parties: FAA/FSDO - NTSB case key (mKey): 93571 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA16CA246 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/93571/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=93571 - Page: https://openairdocs.org/ntsb/ERA16CA246 ## Probable cause The flight's encounter with unforecast extreme turbulence, which resulted in a loss of airplane control and structural damage. ## 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 (probable cause); cases with it: [Mooney M20J, 2 cases](https://openairdocs.org/ntsb-findings/03032000/cases.md?model=5870219), [All aircraft, 92 cases](https://openairdocs.org/ntsb-findings/03032000/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute-change of cruise level: Turbulence encounter](https://openairdocs.org/ntsb-events/360); cases with it: [Mooney M20J, 2 cases](https://openairdocs.org/ntsb-events/360/sequence.md?model=5870219), [All aircraft, 423 cases](https://openairdocs.org/ntsb-events/360/sequence.md) - [Enroute-change of cruise level: Loss of control in flight](https://openairdocs.org/ntsb-events/240) (defining event); cases with it: [Mooney M20J, 21 cases](https://openairdocs.org/ntsb-events/240/sequence.md?model=5870219), [All aircraft, 5,002 cases](https://openairdocs.org/ntsb-events/240/sequence.md) ## Analysis The pilot stated that he was conducting a cross-country flight and flying in instrument meteorological conditions at 7,000 ft mean sea level (msl) when the airplane encountered turbulence. While climbing to a higher altitude, he encountered extreme turbulence at 8,500 ft msl. The pilot lost control of the airplane, which entered an uncontrolled dive, and descended to 5,600 ft msl before he was able to regain control. The pilot subsequently landed without further incident. A postflight inspection of the airplane revealed substantial damage to the right wing spar. The pilot reported no preexisting mechanical malfunctions or failures with the airplane that would have precluded normal operation; however, he stated that he may have overstressed the airplane during the recovery from the uncontrolled descent. A review of weather data revealed that there were no SIGMETs or AIRMETs for turbulence issued for the area of the accident around the time of the accident. ## Factual narrative The pilot stated that he was conducting a cross-country flight and flying in instrument meteorological conditions at an altitude of 7,000 ft mean sea level (msl) when the airplane encountered turbulence. While climbing to a higher altitude, he encountered extreme turbulence at 8,500 ft msl. The pilot lost control of the airplane, which entered an uncontrolled dive, and descended to 5,600 ft msl before he was able to regain control. The pilot subsequently landed without further incident. A post-flight inspection of the airplane revealed substantial damage to the right wing spar. The pilot reported no preexisting mechanical malfunctions or failures with the airplane that would have precluded normal operation; however, he stated that he may have overstressed the airplane during the recovery from the uncontrolled descent. A review of weather data revealed that there were no SIGMETs or AIRMETs for turbulence issued for the area of the accident, around the time of the accident. ## Aircraft - Registration: [N3877H](https://openairdocs.org/deregistered/N3877H-2018-05-30), registration cancelled 2018-05-30, S/N 24-0972, built 1980 (OpenAirDocs) - Reported make and model: MOONEY M20 (J) - Registry model: [Mooney M20J](https://openairdocs.org/model/mooney-m20j) (registry code 5870219) (OpenAirDocs) - Registry engine: [Lycoming I0360 SER A&C](https://openairdocs.org/engine/lycoming-i0360-ser-a-c) (registry code 41511, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 24-0972 - Year built: 1980 - Airframe hours: 7548 - Engines: LYCOMING IO360 SER A&C 200 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, May 13, 2016 - Departed: PAH, PADUCAH, KY - Destination: ECP, PANAMA CITY, FL - Flight plan: IFR - Equipment: Satellite tracking device, Onboard weather, Auto-pilot, Stall warning system ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 58; injuries: none; private; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 3, with waivers/limitations; seat: left; restraint: 3-point; flight hours: 1,446 total, 1,134 in this make and model, 1,443 as pilot in command, 14.8 in the last 90 days, 13.3 in the last 30 days, 3 in the last 24 hours ## Weather - Conditions: Instrument (IMC), Day - Wind: 170° at 8 knots - Visibility: 10 statute miles - Temperature: 84 °F, dew point 72 °F - Altimeter: 30.10 inHg - Turbulence: Unknown - Observed at: KMRC, 12 nm away ## Docket (3 files) The files NTSB released with the investigation on August 11, 2017, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=93571. 1.3 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 1.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40455217&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Witness Statements (item 2, .PDF, 23 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40455218&FileExtension=.PDF&FileName=Witness%20Statements-Master.PDF - Weather Reports and Records (item 3, .PDF, 32 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40455219&FileExtension=.PDF&FileName=Weather%20Reports%20and%20Records-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.