# NTSB CHI05CA092: Mooney M20M, N21816, Lincoln, NE, April 10, 2005 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: April 10, 2005, 13:30 local (18:30 UTC) - Place: Lincoln, NE - Coordinates: 40.850833, -96.759162 - Nearby events: https://openairdocs.org/map.md?lat=40.8508&lon=-96.7592&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report June 28, 2006 - Report: Approved by Office Director - NTSB case key (mKey): 61364 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI05CA092 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/61364/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=61364 - Page: https://openairdocs.org/ntsb/CHI05CA092 ## Probable cause The pilot inadvertently exceeded the design limits of the airplane during the recovery from the loss of control due to the unanticipated severe turbulence. Factors to the accident were the turbulence in clouds and the main landing gear collapse. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight encounter with weather, cruise - weather condition - turbulence in clouds (contributing factor) - Loss of control - in flight, cruise - Airframe/component/system failure/malfunction, descent - uncontrolled - design stress limits of aircraft - exceeded, pilot in command (cause) - wing - overload (cause) - Forced landing, emergency descent/landing - Main gear collapsed, taxi - from landing - landing gear,main gear - overload (contributing factor) ## Analysis The airplane sustained substantial damage during recovery from a loss of control during instrument meteorological conditions (IMC) when the airplane encountered severe turbulence at 16,000 feet mean sea level (msl) and recovered at 6,000 feet msl before executing a precautionary landing. The commercial pilot reported that a thorough preflight weather briefing was obtained from the Flight Service Station (FSS). Due to severe weather reported in Kansas and Colorado, the pilot filed a route of flight that was further north through Nebraska. The pilot reported, "While in level cruise flight in IMC at 16,000' I suddenly encountered an unanticipated severe downdraft that caused a temporary loss of control of the aircraft. The plane was suddenly in a rapidly descending spiral. I was able to regain control and level off at 6,000' in VMC." The pilot executed a precautionary landing at the nearest suitable airport. While taxiing to the ramp, the right landing gear collapsed. The inspection of the airplane revealed that the right landing gear had collapsed, the wing spar was bent, and the wings were wrinkled. A representative from the airplane's manufacturer reported that the damage to the airplane indicated that the airplane experienced about 12g's of force during the recovery from the turbulence event. The airplane's storm scope was tested by a repair facility after the accident and it tested within normal specifications. There had been no pilot reports (PIREPS) along the pilot's route of flight at the time of the weather brief. A review of the air traffic control (ATC) tapes revealed that the ATC controller and the pilot did not have any communications about turbulence or severe weather prior to the upset occurring. ## Factual narrative On April 10, 2005, at 1330 central daylight time, a Mooney M20M, N21816, sustained substantial damage during recovery from a loss of control when the airplane encountered severe turbulence at 16,000 feet mean sea level (msl) and recovered at 6,000 feet msl before executing a precautionary landing at Lincoln Airport (LNK), Lincoln, Nebraska. The commercial pilot was not injured. The 14 CFR Part 91 business flight departed Columbia, Missouri, on an instrument flight rules (IFR) flight plan at 1130, and was en route to Scottsbluff, Nebraska, to refuel before proceeding to Portland, Oregon, the final destination. Instrument meteorological conditions (IMC) prevailed at the time of the encounter with turbulence. The pilot reported that a thorough pre-flight weather briefing was obtained from the Columbia, Missouri, Flight Service Station (FSS). Due to severe weather reported in Kansas and Colorado, the pilot filed a route of flight that was further north through Nebraska. The pilot reported, "While in level cruise flight in IMC at 16,000' I suddenly encountered an unanticipated severe downdraft that caused a temporary loss of control of the aircraft. The plane was suddenly in a rapidly descending spiral. I was able to regain control and level off at 6,000' in VMC. After re-establishing contact with Minneapolis Center I diverted to Lincoln, NE (KLNK), the nearest suitable airport." The pilot also reported, "The approach and landing were uneventful. Gear-down indications were normal. However, when turning off Runway 18 onto the taxiway the right main gear collapsed." A Federal Aviation Administration inspector examined the airplane. The inspection revealed that the right landing gear had collapsed, the wing spar was bent, and the wings were wrinkled. The pilot reported to the inspector that the landing gear circuit breaker had popped after the recovery from the encounter with turbulence. A Mooney Airplane Company representative reported that the damage to the airplane indicated that the airplane experienced about 12g's of force during the recovery from the turbulence event. The pilot reported that the storm scope on the airplane was very reliable and that it did not indicate any severe weather at the time of the upset. The storm scope was tested by a repair facility after the accident and it performed within normal specifications. The Columbia FSS reported that no pilot reports (PIREPS) along the pilot's route of flight were available at the time of the weather brief. The reported severe weather was located over Kansas at the time of the brief. A review of the air traffic control (ATC) tapes from Minneapolis Center revealed that the ATC controller and the pilot did not have any communications about turbulence or severe weather prior to the upset occurring. ## Aircraft - Registration: [N21816](https://openairdocs.org/deregistered/N21816-2005-12-12), registration cancelled 2005-12-12, S/N 27-0277, built 1999 (OpenAirDocs) - Reported make and model: Mooney M20M - Registry model: [Mooney M20M](https://openairdocs.org/model/mooney-m20m) (registry code 5870222) (OpenAirDocs) - Registry engine: [Lycoming TI0-540 series](https://openairdocs.org/engine/lycoming-ti0-540-series) (registry code 41533, turbo-prop) (OpenAirDocs) - Category: Airplane - Serial number: 27-0277 - Engines: Lycoming TIO-540-AF1B 270 horsepower reciprocating - Damage: Substantial damage - Flight: Business, Part 91 - Registered owner: Wings Northwest LLC - Airworthiness certificate: Standard, Normal - Departed: COU, Columbia, MO - Destination: BFF, Scottsbluff, NE - Flight plan: IFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 68; flight instructor, commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 3; flight hours: 3,902 total, 722 in this make and model, 24 in the last 90 days, 16 in the last 30 days, 3 in the last 24 hours ## Weather - Conditions: Instrument (IMC), Day ## 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 20050410007069A](https://openairdocs.org/incident/20050410007069A), Apr 10, 2005: Mooney M20M, Lincoln, NE, Substantial damage. (-23) PIC (sole occupant) was at 16,000 on IFR fp from cou to pdx with scheduled fuel stops at bff and boi. At approx 30-35 mi se of lnk, encountered… ## Docket (1 files) The files NTSB released with the investigation on April 5, 2006, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=61364. 283 KB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 283 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40366550&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.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.