# NTSB ERA20LA312: Quad City Challenger, N56906, Sweetwater, TN, September 10, 2020 - Type: NTSB accident investigation - Classification: Accident · Fatal · Class 3 · Limited · Final report - Date: September 10, 2020, 16:00 local (20:00 UTC) - Place: Sweetwater, TN · backyard of residence - Coordinates: 35.555, -84.519721 - Nearby events: https://openairdocs.org/map.md?lat=35.5550&lon=-84.5197&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Defining event: [Initial climb: Loss of control in flight](https://openairdocs.org/ntsb-events/240) - Highest injury: Fatal - Injuries: 1 fatal - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Eastern Region Aviation - Parties: Rotax, FAA/FSDO - NTSB case key (mKey): 101946 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA20LA312 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/101946/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=101946 - Page: https://openairdocs.org/ntsb/ERA20LA312 ## Probable cause A loss of control for reasons that could not be determined based on the available information. ## 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: [Quad City Ultralight Acft CHALLENGER II, 1 case](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=059010Q), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Not determined](https://openairdocs.org/ntsb-findings/05000000): Not determined › Not determined · Unknown/Not determined (probable cause); cases with it: [Quad City Ultralight Acft CHALLENGER II, 1 case](https://openairdocs.org/ntsb-findings/05000000/cases.md?model=059010Q), [All aircraft, 2,247 cases](https://openairdocs.org/ntsb-findings/05000000/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 control in flight](https://openairdocs.org/ntsb-events/240) (defining event); cases with it: [Quad City Ultralight Acft CHALLENGER II, 1 case](https://openairdocs.org/ntsb-events/240/sequence.md?model=059010Q), [All aircraft, 5,002 cases](https://openairdocs.org/ntsb-events/240/sequence.md) - [Initial climb: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Quad City Ultralight Acft CHALLENGER II, 2 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=059010Q), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis Despite being told by the airplane owner that he could taxi, but not fly, the airplane, the pilot conducted a high-speed taxi and took off. About 250 to 300 ft above ground level, the airplane suddenly nosed over. The owner, who witnessed the takeoff, stated that the engine was not seized, and the propeller was still spinning when the airplane disappeared behind trees. Examination revealed no anomalies with the airframe or engine that would have precluded normal operation, and damage signatures and witness accounts indicated that the engine was producing power at the time of the accident. Toxicology testing detected THC-COOH, the inactive metabolite of THC, in the pilot’s liver and lung tissue. Gabapentin, promethazine, norchlorcyclizine, duloxetine, citalopram, its metabolite n-desmethylcitalopram, and trazodone were detected in the pilot’s liver tissue; except for trazodone, these compounds were also detected in the pilot’s muscle tissue. Since only the inactive metabolite of THC was detected, it is unlikely that the effects from the pilot’s use of cannabis were a factor in this accident. Autopsy findings did not show evidence of any potentially sudden incapacitating event. Thus, it is unlikely that the pilot’s medical conditions or his use of detected prescription medications contributed to the accident. Although the circumstances of the accident are consistent with a loss of control, the reason for the loss of control could not be determined based on the available information. ## Factual narrative The airplane logbooks only contained the initial 5 flight hours required for certification. The airplane was 29 years old, and the total aircraft time could not be determined. The Rotax 582 engine had either a 300-hr or 5-year time between overhaul (TBO). There were no records to indicate that the engine ever received an overhaul. On September 10, 2020, at 1600 eastern daylight time, an experimental Quad City Challenger II light sport airplane, N56906, was substantially damaged when it was involved in an accident near Sweetwater, Tennessee. The pilot was fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations (CFR) Part 91 personal flight. The owner recently purchased the airplane. According to the owner, he had known the pilot for a couple years and stated he had “flown lots of Challengers” and had “extensive experience with them.” He told the pilot that the airplane did not have insurance, was not registered, and did not have a current annual inspection; he planned to have the annual inspection completed a few days later. He told the pilot that he could taxi the airplane, but not fly it. The owner watched the pilot start the airplane and begin a high-speed taxi. The airplane took off and climbed out straight and level for about 1/2 mile, to a height of about 250 to 300 ft above ground level. The owner said that the airplane was flying “normal” and the engine sounded “normal” then the airplane suddenly nosed over. He stated that the engine was not seized, and the propeller was still spinning when the airplane disappeared behind trees. The previous pilot to fly the airplane was the ferry pilot a couple of weeks before the accident. He stated that the airplane flew “fine” and “climbed like an angel.” He did not complete the ferry flight due to turbulence in mountain passes; the airplane was disassembled and trucked the rest of the way. The Regional Forensic Center, Knoxville, Tennessee, performed an autopsy of the pilot. The pilot's cause of death was multiple blunt force injuries. No significant natural disease was identified. FAA Forensic Sciences Laboratory toxicology testing detected the inactive metabolite of tetrahydrocannabinol (THC), carboxy-delta-9-tetrahydrocannabinol (THC-COOH), in the pilot’s liver and lung tissue. Gabapentin, promethazine, norchlorcyclizine, duloxetine, citalopram, its metabolite n-desmethylcitalopram, and trazodone were detected in the pilot’s liver tissue; except for trazodone, these compounds were also detected in the pilot’s muscle tissue. Toxicology testing performed for the Regional Forensic Center was negative for alcohol and other tested for drugs of abuse in the pilot’s muscle tissue. THC is the active component in cannabis, a Schedule I controlled substance; tetrahydrocannabinol carboxylic acid is an inactive metabolite. THC causes mood-altering effects, euphoria, and relaxation for a few hours after use. Real-world and simulated flight research noted impairment for up to 24hours after use, including a lack of pilot awareness of impairment or decreased performance. Gabapentin, commonly marketed as Neurontin, is an antiseizure medication that is also used to treat chronic nerve pain and postherpetic neuralgia (shingles). It carries a warning that it “may cause dizziness, somnolence and other symptoms and signs of central nervous system depression” and patients should be advised not to operate complex machinery “until they have gained sufficient experience on gabapentin to assess whether gabapentin impairs their ability to perform such tasks.” Gabapentin has a long half-life that ranges from 6.5 to 52 hours. Promethazine is a prescription medication used to relieve allergy symptoms, for sedation before surgery, and to prevent and control nausea and vomiting that may occur after surgery. Drowsiness can occur and patients should be cautioned against driving or operating machinery while using promethazine. One of the metabolites of hydroxyzine is the inactive metabolite norchlorcyclizine. Hydroxyzine is prescribed for symptomatic relief of anxiety and tension, managing itching due to allergies, and as a sedative for general anesthesia. Drowsiness can occur and patients should be cautioned against driving or operating machinery while using hydroxyzine. Duloxetine, commonly marketed as Cymbalta, is a prescription medication used to treat depression, anxiety, and chronic musculoskeletal pain. Duloxetine carries the warning that its use may impair mental and physical ability to perform potentially hazardous tasks. The therapeutic range is 22 to 55 ng/mL and it has a half-life of 8 to 17 hours. Citalopram or escitalopram is a prescription antidepressant medication marketed as Celexa. It carries the warning that its use may impair mental of physical ability for performing hazardous tasks. The therapeutic range for citalopram is 50 to 110 ng/mL and the half-life is 25 to 35 hours. Citalopram and escitalopram are two of the four FAA-approved antidepressant medications. Trazodone is a medication prescribed to treat depression, anxiety, and insomnia. Trazodone can be sedating. It comes with this warning, “Trazodone hydrochloride tablets may cause somnolence or sedation and may impair the mental and/or physical ability required for the performance of potentially hazardous tasks. Patients should be cautioned about operating hazardous machinery, including automobiles, until they are reasonably certain that the drug treatment does not affect them adversely.” The therapeutic range is 500 to 2,500 ng/mL and it has a half-life of 4 to 7 hours. The pilot's logbook was not recovered. On the application for his most recent medical certificate, dated April 28, 1995, he reported 68 total hours of flight experience, including 1 hour in the previous 6 months. The airplane impacted terrain in the backyard of a residential property. The debris path was about 30 ft long and oriented on a magnetic heading of 180°. Ground scars at the accident siteand damage to the airplane were consistent with the airplane impacting terrain in a nose-low attitude. A postimpact fire consumed most of the wreckage; all major structural components of the airplane were located within the debris field. Initial examination of the airplane by a Federal Aviation Administration inspector verified flight control continuity from the cockpit to all primary flight control surfaces. The engine crankcase was intact. Two of the propeller blades were bent aft, the other separated about midspan; all of the blades were thermally damaged. The engine was equipped with an aftermarket belt drive reduction system that is normally found on Challenger aircraft. Both carburetors were impact and fire damaged and displaced from their respective intake sockets. The electrical and ignition systems were partially fire damaged. Some of the spark plugs were impact damaged, the electrodes appeared normal in wear and color as compared to a manufacturer’s inspection chart. The fuel system and fuel lines were fire damaged and mostly consumed by fire. The cylinder head and cylinders were removed and examined. No anomalies seen with either the cylinder head, pistons, piston rings or cylinders. No signs of metal transfer or seizure marks were observed between the cylinders and pistons. ## Aircraft - Registration: [N56906](https://openairdocs.org/deregistered/N56906-2021-08-07), registration cancelled 2021-08-07, S/N CH2-0901-2134, built 2004 (OpenAirDocs) - Reported make and model: QUAD CITY CHALLENGER (II) - Registry model: [Quad City Ultralight Acft CHALLENGER II](https://openairdocs.org/model/quad-city-ultralight-acft-challenger-ii) (registry code 059010Q) (OpenAirDocs) - Registry engine: [Rotax 582DCDI](https://openairdocs.org/engine/rotax-582dcdi) (registry code 55562, 2 cycle) (OpenAirDocs) - Category: Airplane - Serial number: CH2-0901-2134 - Year built: 2004 - Engines: Rotax 582 65 horsepower reciprocating - Damage: Substantial damage - Fire: On-Ground - Flight: Personal, Part 91 - Airworthiness certificate: Special, Experimental light sport (Special) - Destination: Same as departure - Airport: TN64, West Wind Airpark, runway 02, 1,100 × 50 ft, grass/turf - Equipment: Unknown ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 53; injuries: fatal; private; airplane ratings: single-engine land; medical: sport pilot, without waivers/limitations; seat: front; toxicology performed; flight hours: 68 total ## Weather - Conditions: Visual (VMC), Day - Wind: 10° at 5 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 88 °F, dew point 70 °F - Altimeter: 30.13 inHg - Observed at: TYS, 30 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 20200910014529A](https://openairdocs.org/incident/20200910014529A), Sep 10, 2020: Quad City Ultralight Acft Corp CHALLENGER II, Niota, TN, Destroyed, 1 fatal. Pilot taxied and went airborne. Flight lasted between 0.5 and 1.0 miles, before N56906 crash landed killing pilot. Flight controls connected and operational.… ## Docket (8 files) The files NTSB released with the investigation on September 22, 2022, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=101946. 6.8 MB in all. - Witness statements (item 1, PDF, 4 pages, 3.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12618464&FileExtension=pdf&FileName=Witness%20Statements_Redacted-Rel.pdf - FAA inspector's statement (item 2, PDF, 4 pages, 132 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12621483&FileExtension=pdf&FileName=MOR%20FAA%20Insepctor-Rel.pdf - Engine examination report (item 3, PDF, 6 pages, 120 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12619237&FileExtension=pdf&FileName=N56906%20Rotax%20Investigation%20Field%20Notes-Rel.pdf - Toxicological report (item 4, PDF, 2 pages, 306 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12394413&FileExtension=pdf&FileName=Toxicology_Redacted-Rel.pdf - NTSB medical report (item 5, PDF, 5 pages, 256 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12395394&FileExtension=pdf&FileName=ERA20LA312_Sweetwater_TN_Medical_Factual_FINAL_052721-Rel.pdf - Release of aircraft wreckage, NTSB form 6120.15 (item 6, PDF, 1 page, 911 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12653245&FileExtension=pdf&FileName=Wreckage%20release_Redacted-Rel.pdf - Investigation photographs (item 7, PDF, 5 pages, 1.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12619504&FileExtension=pdf&FileName=Photo%20Array-Rel.pdf - Autopsy memo for record (item 8, PDF, 1 page, 117 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12621149&FileExtension=pdf&FileName=Autopsy%20Memo%20for%20Record-Rel.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.