# NTSB ERA15FA049: Mooney M20C, N6581U, Lewisburg, WV, November 10, 2014 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Field investigation · Final report - Date: November 10, 2014, 12:58 local (17:58 UTC) - Place: Lewisburg, WV - Coordinates: 37.865276, -80.399444 - Nearby events: https://openairdocs.org/map.md?lat=37.8653&lon=-80.3994&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Defining event: [Initial climb: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) - Highest injury: Serious injuries - Injuries: 1 serious - Status: Completed, report May 16, 2016 - Report: Approved by Office Director - NTSB office: Eastern Region Aviation - Parties: FAA/FSDO, Lycoming - NTSB case key (mKey): 90380 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA15FA049 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/90380/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=90380 - Page: https://openairdocs.org/ntsb/ERA15FA049 ## Probable cause The pilot's failure to maintain airspeed while maneuvering, which resulted in the airplane exceeding its critical angle of attack and experiencing an aerodynamic stall. Contributing to the accident were abnormal engine operation due to improper magneto-to-engine ignition timing and the pilot's failure to have the airplane inspected before the flight as required by the special flight permit. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Performance/control parameters: angle of attack](https://openairdocs.org/ntsb-findings/01062042): Aircraft › Aircraft oper/perf/capability · Capability exceeded (probable cause); cases with it: [Mooney M20C, 7 cases](https://openairdocs.org/ntsb-findings/01062042/cases.md?model=5870208), [All aircraft, 990 cases](https://openairdocs.org/ntsb-findings/01062042/cases.md) - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Mooney M20C, 16 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=5870208), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/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: [Mooney M20C, 7 cases](https://openairdocs.org/ntsb-findings/01062010/cases.md?model=5870208), [All aircraft, 1,681 cases](https://openairdocs.org/ntsb-findings/01062010/cases.md) - [Action: lack of action](https://openairdocs.org/ntsb-findings/02041030): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Mooney M20C, 3 cases](https://openairdocs.org/ntsb-findings/02041030/cases.md?model=5870208), [All aircraft, 792 cases](https://openairdocs.org/ntsb-findings/02041030/cases.md) - [Ignition system: magneto/distributor](https://openairdocs.org/ntsb-findings/01057414): Aircraft › Aircraft power plant · Incorrect service/maintenance (probable cause); cases with it: [Mooney M20C, 1 case](https://openairdocs.org/ntsb-findings/01057414/cases.md?model=5870208), [All aircraft, 101 cases](https://openairdocs.org/ntsb-findings/01057414/cases.md) - [Info processing/decision: decision making/judgment](https://openairdocs.org/ntsb-findings/02041520): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Mooney M20C, 11 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md?model=5870208), [All aircraft, 3,098 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Initial climb: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) (defining event); cases with it: [Mooney M20C, 6 cases](https://openairdocs.org/ntsb-events/342/sequence.md?model=5870208), [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/sequence.md) - [Emergency descent: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Mooney M20C, 21 cases](https://openairdocs.org/ntsb-events/440/sequence.md?model=5870208), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) - [Emergency descent: Loss of control in flight](https://openairdocs.org/ntsb-events/240); cases with it: [Mooney M20C, 10 cases](https://openairdocs.org/ntsb-events/240/sequence.md?model=5870208), [All aircraft, 5,002 cases](https://openairdocs.org/ntsb-events/240/sequence.md) - [Emergency descent: Aerodynamic stall/spin](https://openairdocs.org/ntsb-events/241); cases with it: [Mooney M20C, 8 cases](https://openairdocs.org/ntsb-events/241/sequence.md?model=5870208), [All aircraft, 1,529 cases](https://openairdocs.org/ntsb-events/241/sequence.md) - [Uncontrolled descent: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Mooney M20C, 39 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=5870208), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The private pilot/owner purchased the airplane 1 month before the accident flight; the airplane had no associated maintenance logs. The pilot applied for and received a special flight permit to ferry the airplane to a facility where maintenance could be performed with the stipulation that a qualified mechanic inspect the airplane before the flight to ensure that it was safe for flight; however, the pilot failed to have this inspection performed. According to one witness, the taxi, takeoff roll, and initial climb of the accident flight appeared and sounded normal. After reaching about 200 ft above ground level, the airplane leveled off and continued to fly over the runway centerline. Before reaching the end of the runway, the airplane entered a slight left bank, which quickly steepened; the airplane's nose dropped and then returned to a level attitude before it descended out of view. Another witness stated that, about the time that the airplane entered the left bank, it sounded like the engine had lost power but that, shortly thereafter, full engine power appeared to have been restored. A third witness stated that the airplane descended as it oscillated left to right at a relatively steep angle, leveled again, and pitched up and then down just before impact. Postaccident examination of the airframe revealed no evidence of any mechanical anomalies. During examination of the engine, the magneto-to-engine ignition timing was found to be significantly out of specification for both magnetos, which likely resulted in abnormal engine operation during the climb and may account for the observed leveling off of the airplane just after takeoff; however, it could not be determined whether this was due to reduced engine power output or the pilot's response to an observed anomaly. The witnesses' observations of the takeoff and left turn indicated that the pilot may have been maneuvering for a forced landing or returning to the airport. Their observations are also consistent with the pilot failing to maintain adequate airspeed and the airplane exceeding its critical angle-of-attack and experiencing a subsequent aerodynamic stall. ## Factual narrative The four-seat, low wing, retractable gear airplane was manufactured in 1962. It was powered by a Lycoming O-360-A1A 180-hp reciprocating engine, equipped with a Hartzell two-blade, constant speed aluminum propeller. The date of the airplane's most recent annual inspection could not be determined. The pilot/owner reported that the airplane had been recently repossessed from the previous owner, and he had purchased it the month prior to the accident without any associated maintenance records. He had applied for and received a special flight (ferry) permit from the FAA to return the airplane to his home airport. The ferry permit required that an inspection be performed prior to the flight by an appropriately-certified mechanic or repair station, to determine if the aircraft was safe for flight. The pilot indicated that this inspection was not performed, and no records of such an inspection were found during the investigation. On November 10, 2014, about 1258 eastern standard time, a Mooney M20C, N6581U, was substantially damaged when it impacted a fence and terrain shortly after takeoff from Greenbrier Valley Airport (LWB), Lewisburg, West Virginia. The private pilot received serious injuries. Day visual meteorological conditions prevailed and no flight plan was filed for the flight, which was destined for Hanover County Municipal Airport (OFP), Richmond, Virginia. The ferry flight was conducted under the provisions of Title 14 Code of Federal Regulations Part 91. According to a witness who was working at the airport, the pilot taxied to the beginning of runway 04, paused for a brief period, and then began the takeoff roll. The airplane lifted off within the first 2,000 feet of the 7,003-foot-long runway. The takeoff roll and initial climb appeared normal, and the engine sounded "typical." At about 200 feet above ground level the airplane leveled off, and continued down the runway centerline. He observed that the landing gear remained down, and the flaps remained partially deployed. The airplane entered a slight left banking turn, which quickly increased to a "very sharp" left bank, and the nose "dropped." He observed the airplane return to a level attitude as it descended out of view. A second witness stated that as the airplane began its steep left bank, the wings were "straight up and down" with the left wing pointed toward the ground. He stated at that point, "it didn't sound like he had any power", and before it went out of his view, the engine "appeared to rev to full power". A third witness located in a parking lot near the departure end of the runway saw the airplane as it was flying toward the northwest, perpendicular to the runway. She stated that it was "wig-wagging," which she further described as rolling from left to right at a relatively steep angle "considerably greater than normal takeoffs" she had seen. She stated that the airplane then levelled its bank angle, but then pitched up and shortly thereafter the "nose came down." Thepilot stated that he could not recall the sequence of events following the airplane's takeoff and initial climb. The 1315 recorded weather observation at LWB included: calm wind, 10 miles visibility, clear skies, temperature 16 degrees C, dew point 2 degrees C; barometric altimeter 30.07 inches of mercury. According to Federal Aviation Administration (FAA) records, the pilot held a private pilot certificate issued January 13, 2007, with ratings for airplane single-engine land, multiengine land, and instrument airplane. His most recent third-class medical certificate was issued on April 18, 2013, with a restriction of "must wear corrective lenses." The pilot reported a total of 3,500 flight hours of experience, of which 900 were in the accident airplane make and model. The airplane impacted a fence and terrain in a pasture about 1/4 mile to the left of the runway 04 centerline, about 1,000 feet prior to the departure end of the runway. The debris path began at the initial impact point, which was identified as a broken fence post, and extended about 50 yards on a 323-degree magnetic heading to the main wreckage. There was no evidence of pre or post impact fire. All major components of the airplane were co-located with the main wreckage, with the exception of the left main landing gear, located about 15 feet from the initial impact point, and the propeller/hub assembly, which was located about 10 feet to the southwest of the main wreckage. The left wing sustained leading edge impact damage and the left flap was separated from its outboard 3 attachment points. A section of the right wing was bent downward about 5 feet from the wing tip. The empennage was mostly undamaged except for the left horizontal stabilizer, which sustained leading edge impact damage. Flight control continuity was confirmed from the cockpit controls to all control surfaces, with the exception of the left flap, which was impact damaged. Additionally, the left seat rudder pedals were impinged by damaged structure. The right wing fuel tank contained fuel consistent with the color and odor of 100LL aviation fuel; the left wing tank was breached and was devoid of fuel. First responders estimated that about 20 gallons of fuel had leaked onto the ground under the left wing. When electrical power was applied to the airplane, the right fuel gauge indicated about ¾ full, the left gauge indicated about ¼ full. The cockpit exhibited impact and crush damage. The seats remained attached to the seat rails, the left seatbelt was found intact and unbuckled. The fuel selector valve was found in the "LEFT" tank position. The elevator trim indication could not be determined due to impact damage. The cockpit engine controls were found with the throttle slightly inward from idle position, and the shaft was bent downward about 45 degrees. The mixture control was found about one-half inch out from the full rich (in) position. The propeller control was found in the full forward position. The flaphandle was in the "UP" position and the indicator position could not be determined due to damage. The landing gear handle grip was separated from the bar, and the bar was found in the landing gear up position. Battery power was applied to the airplane and the operation of the stall warning system was confirmed. The engine remained secure to its mounts, which were attached at all four corners of the firewall. The propeller was impact-separated from the crankshaft flange. One propeller blade displayed an impact mark on the leading edge approximately 2 inches from the tip, exhibited chordwise scratching, and was bent aft approximately 14 inches from the tip. The other blade had one leading edge nick approximately 1 inch from the blade tip; no chordwise scratching was present. Engine mechanical continuity, valve action, and thumb compression on all cylinders were confirmed by hand rotation of the engine at the propeller flange. A borescope examination of each cylinder revealed that the #4 intake valve showed signs of erosion on the valve seat, all cylinder walls and piston tops were unremarkable. The engine-to-magneto timing was measured and found to be approximately 48 degrees before top dead center. The manufacturer's specification was 25 degrees. Both magnetos produced spark through all the ignition leads when turned by an electric hand drill. The carburetor was impact separated and exhibited soot deposits in its throat. No other anomalies were noted with the fuel system components, and fuel present in the carburetor bowl tested negative for the presence water. ## Aircraft - Registration: [N6581U](https://openairdocs.org/deregistered/N6581U-2018-04-24), registration cancelled 2018-04-24, S/N 2363, built 1962 (OpenAirDocs) - Reported make and model: MOONEY M20C - Registry model: [Mooney M20C](https://openairdocs.org/model/mooney-m20c) (registry code 5870208) (OpenAirDocs) - Registry engine: [Lycoming O&VO-360 series](https://openairdocs.org/engine/lycoming-o-vo-360-series) (registry code 41514, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 2363 - Year built: 1962 - Engines: LYCOMING O-360-A1A 180 horsepower reciprocating - Damage: Substantial damage - Flight: Ferry, Part 91 - Operator: STONEMAN EXCAVATING Co. INC - Registered owner: STONEMAN EXCAVATING Co. INC - Airworthiness certificate: Standard, Normal - Departed: LWB, Lewisburg, WV - Destination: OFP, Ashland, VA - Airport: LWB, Greenbrier Valley, runway 04, 7,003 × 150 ft, asphalt - Equipment: Stall warning system ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 65; injuries: serious; private; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 3, with waivers/limitations; seat: left; restraint: lap only; flight hours: 3,500 total, 900 in this make and model ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 61 °F, dew point 36 °F - Altimeter: 30.06 inHg - Observed at: KLWB ## 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 20141110020559A](https://openairdocs.org/incident/20141110020559A), Nov 10, 2014: Mooney M20C, Lewisburg, WV, Substantial damage. During the climbout on runway 4 at approximately an altitude of 500-700 feet AGL, the aircraft leveled off for a short period of time and then turned hard left… ## Docket (8 files) The files NTSB released with the investigation on April 29, 2016, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=90380. 5.6 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 835 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40439477&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Witness Statements (item 2, .PDF, 346 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40439478&FileExtension=.PDF&FileName=Witness%20Statements-Master.PDF - Summary of Correspondence with the FAA (item 3, .PDF, 88 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40439479&FileExtension=.PDF&FileName=Summary%20of%20Correspondence%20with%20the%20FAA-Master.PDF - Maps or Charts of Accident Area (item 4, .PDF, 979 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40439480&FileExtension=.PDF&FileName=Maps%20or%20Charts%20of%20Accident%20Area%20-Master.PDF - Photo Array (item 5, .PDF, 2.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40439481&FileExtension=.PDF&FileName=Photo%20Array-Master.PDF - Special Flight Permit (item 6, .PDF, 996 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40439482&FileExtension=.PDF&FileName=Special%20Flight%20Permit-Master.PDF - Statement of Party Representatives to NTSB Investigation (item 7, .PDF, 258 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40439483&FileExtension=.PDF&FileName=Statement%20of%20Party%20Representatives%20to%20NTSB%20Investigation-Master.PDF - Release of Aircraft Wreckage, NTSB Form 6120.15 (item 8, .PDF, 34 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40439484&FileExtension=.PDF&FileName=Release%20of%20Aircraft%20Wreckage,%20NTSB%20Form%206120.15-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.