# NTSB CEN10LA429: Warth Dennis J Classic Sport S-18, N216TB, Tea, SD, July 24, 2010 - Type: NTSB accident investigation - Classification: Accident · Fatal · Limited investigation · Final report - Date: July 23, 2010, 20:20 local (Jul 24, 2010, 01:20 UTC) - Place: Tea, SD - Coordinates: 43.457221, -96.80194 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=43.4572&lon=-96.8019&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: Fatal - Injuries: 1 fatal - Status: Completed, report May 19, 2011 - Report: Approved by Office Director - NTSB office: Central Region - Parties: FAA Rapid City FSDO - NTSB case key (mKey): 76739 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN10LA429 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/76739/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=76739 - Page: https://openairdocs.org/ntsb/CEN10LA429 ## Probable cause A loss of engine power for undetermined reasons and the pilot's loss of airplane control, which led to an aerodynamic stall. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Engine (reciprocating)](https://openairdocs.org/ntsb-findings/01058500): Aircraft › Aircraft power plant · Not specified (probable cause); cases with it: [Warth Dennis J CLASSIC SPT AC S-18, 1 case](https://openairdocs.org/ntsb-findings/01058500/cases.md?model=05617F5), [All aircraft, 497 cases](https://openairdocs.org/ntsb-findings/01058500/cases.md) - [Performance/control parameters: airspeed](https://openairdocs.org/ntsb-findings/01062010): Aircraft › Aircraft oper/perf/capability · Not attained/maintained; cases with it: [Warth Dennis J CLASSIC SPT AC S-18, 1 case](https://openairdocs.org/ntsb-findings/01062010/cases.md?model=05617F5), [All aircraft, 1,681 cases](https://openairdocs.org/ntsb-findings/01062010/cases.md) - [Action: incorrect action selection](https://openairdocs.org/ntsb-findings/02041010): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Warth Dennis J CLASSIC SPT AC S-18, 1 case](https://openairdocs.org/ntsb-findings/02041010/cases.md?model=05617F5), [All aircraft, 397 cases](https://openairdocs.org/ntsb-findings/02041010/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: [Warth Dennis J CLASSIC SPT AC S-18, 1 case](https://openairdocs.org/ntsb-events/342/sequence.md?model=05617F5), [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/sequence.md) - [Initial climb: Aerodynamic stall/spin](https://openairdocs.org/ntsb-events/241); cases with it: [Warth Dennis J CLASSIC SPT AC S-18, 1 case](https://openairdocs.org/ntsb-events/241/sequence.md?model=05617F5), [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: [Warth Dennis J CLASSIC SPT AC S-18, 1 case](https://openairdocs.org/ntsb-events/470/sequence.md?model=05617F5), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis A witness reported that the pilot was flying a maintenance test flight because the airplane engine’s carburetor was replaced with a fuel injection system and a new air filter system was installed. The engine appeared to be developing full power during the takeoff roll. When the airplane was about 500 feet above ground level (agl), it made a left crosswind turn. The witness reported seeing a brief puff of black smoke coming from the engine exhaust. The airplane then entered a descending left turn before encountering a full stall about 100 to 150 feet agl. The airplane impacted a cornfield near the airport in about a 60- to 70-degree nose-down, inverted attitude. Postaccident inspection of the airframe revealed no preimpact anomalies. The inspection of the engine and fuel injection system revealed no preimpact anomalies; however, the mechanical fuel pump and both magnetos were broken by impact forces and could not be tested. No other anomalies were found with the airplane. ## Factual narrative HISTORY OF FLIGHT On July 23, 2010, at 2020 central daylight time, an experimental amateur-built Warth Classic Sport S-18, N216TB, sustained substantial damage when it impacted a cornfield after a loss of engine power shortly after takeoff from runway 16 (3,650 feet by 60 feet asphalt) at the Lincoln County Airport (Y14), Tea, South Dakota. The commercial pilot was fatally injured. The 14 Code of Federal Regulations Part 91 personal flight departed Y14 on a local flight. Visual meteorological conditions prevailed at the time of the accident. No flight plan was filed. A witness reported that he spoke to the pilot shortly before the accident. He stated that the pilot was going to fly the accident airplane on a maintenance test flight because he had recently installed a throttle body fuel injection system in place of the original carburetor. The pilot had also installed new engine baffles and a Vans RV-4 intake scoop. The witness observed the pilot conduct the pre-takeoff and engine run-up procedures. He reported that the engine hesitated and failed to run up to full RPM on the first attempt. The engine “went flat and lost RPM” on the second attempt. He reported that the third run-up was successful and the engine attained full RPM. He reported the takeoff roll was normal with the engine developing full power. The airplane rotated normally and climbed straight ahead to about 500 – 600 feet above ground level (agl). The airplane entered a left crosswind turn. The witness reported that he observed a “brief puff” of dark, black smoke coming from the exhaust. The airplane, which was now about 1/2 mile from the airport, started to lose altitude as it continued in a left turn. The airplane continued in a left bank until it was headed in a westerly direction. The witness stated, “The aircraft entered a full stall, probably 150 to 200 feet off the ground.” Another witness reported that the airplane entered a hard right turn after it had pitched up when it was about 100 to 150 feet agl. He reported that the airplane impacted a cornfield in a 50 to 60 degree nose down attitude, and it appeared that the left wing and nose of the airplane impacted the terrain first. PERSONNEL INFORMATION The pilot, age 31, held a commercial pilot certificate with single-engine and multi-engine airplane land with an instrument airplane rating. He held a second-class medical certificate that was issued in September 2009. The pilot’s logbook indicated that he had about 3,366 total flight hours and about 65 hours in make and model. The last recorded flight in the pilot’s logbook was made on November 18, 2009. AIRCRAFT INFORMATION The two-seat, low-wing, experimental amateur-built Warth Classic Sport S-18, serial number 245, was powered by a Lycoming O-320-D2A 180-horsepower engine and was equipped with a Sensenich propeller. The airplane’s maintenance logbook indicated that the airplane had about 123 total hours, and that the last conditional inspection was conducted on February22, 2010. A Rotec Throttle Body Unit and regulator were installed on the engine, replacing the original carburetor. METEOROLOGICAL INFORMATION At 1956, the surface weather observation at the Joe Foss Field Airport, Sioux Falls, South Dakota, located about 8 miles north of the accident site, was: Wind 150 at 8 knots, visibility 10 miles, broken ceiling at 3,800 feet, temperature 28 degrees Celsius (C), dew point 23 degrees C, and altimeter 29.76 inches of Mercury. WRECKAGE AND IMPACT INFORMATION The airplane wreckage was located in a cornfield near the airport. The damage to the corn stalks and the impact to the wreckage were consistent with the airplane impacting the terrain inverted in about a 60 – 70 degree nose down attitude. The right wing was separated from the fuselage and found about 30 feet from the main wreckage. Federal Aviation Administration inspectors examined the wreckage at the accident site. The inspection of the airframe revealed no pre-impact anomalies. The engine was separated from the airframe for inspection. An Airframe and Powerplant (A&P) mechanic assisted with the engine inspection. The engine inspection revealed that both magnetos were broken and no testing could be performed. The number 2 cylinder was removed from the case and no internal damage to the drive train was noted. The compression was checked by rotating the crankshaft. Compression and suction were confirmed on the three remaining cylinders. Drive train continuity was confirmed. The mechanical fuel pump was broken in two pieces from the impact and could not be tested. There was fuel in the fuel line going to the regulator and fuel in the line between the regulator and the throttle body. All the control cables going to the throttle body were connected. The inspection of the propeller revealed that the blades were bent aft. No chordwise scoring or leading edge gouges or nicks were found on the blades The Rotec Throttle Body unit and regulator were sent to the National Transportation Safety Board’s investigator-in-charge for testing. The throttle body and regulator were visually inspected and installed on a recently overhauled Lycoming O-320 engine. The engine was on a test stand. There were no leaks to the throttle body. The engine was started and operated through the entire range of RPM’s. The engine ran smoothly at 1,500, 2,000, and 2,500 RPM. At 2,600 RPM and at 26 inches of manifold pressure, the engine started to sound slightly rough. There were no anomalies noted during the inspection and engine run. MEDICAL AND PATHOLOGICAL INFORMATION An autopsy of the pilot was conducted at LCM Pathologists, Sioux Falls, South Dakota, on July 24, 2010. The cause of death was multiple blunt trauma secondary to an airplane accident. The FAA Civil Aeronautical Institute prepared a Forensic Toxicology Fatal Accident Report, which indicated negative results for carbon monoxide, cyanide, and ethanol. 38.92 (ug/ml, ug/g) acetaminophen was detected in the urine. ## Aircraft - Registration: [N216TB](https://openairdocs.org/deregistered/N216TB-2013-07-30), registration cancelled 2013-07-30, S/N 245, built 2005 (OpenAirDocs) - Reported make and model: WARTH DENNIS J Classic Sport S-18 - Registry model: [Warth Dennis J CLASSIC SPT AC S-18](https://openairdocs.org/model/warth-dennis-j-classic-spt-ac-s-18) (registry code 05617F5) (OpenAirDocs) - Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: 245 - Airframe hours: 123 - Engines: Lycoming O-320-D2A 180 horsepower reciprocating - Damage: Substantial damage - Flight: Flight test, Part 91 - Operator: Baloun Aviation LLC - Registered owner: Baloun Aviation LLC - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Condition, February 22, 2010 - Departed: Y14, Tea, SD - Destination: Y14, Tea, SD - Airport: Y14, Lincoln County Airport, runway 16, 3,650 × 60 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 31; injuries: fatal; commercial, flight instructor, private; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2; last flight review November 4, 2009; seat: left; flight hours: 3,366 total, 65 in this make and model ## Weather - Conditions: Visual (VMC), Day - Wind: 150° at 8 knots - Visibility: 10 statute miles - Lowest ceiling: 3,800 ft broken - Temperature: 82 °F, dew point 73 °F - Altimeter: 29.76 inHg - Observed at: FSD, 8 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 20100723042829A](https://openairdocs.org/incident/20100723042829A), Jul 23, 2010: Warth Denni CLASSIC SPT, Tea, SD, Destroyed, 1 fatal. On July 23, 2010, pilot [privacy data omitted] flew N216TB, an experimental Warth thorp S-18, on a maintenance test flight around the Tea, SD airport.… ## Docket (10 files) The files NTSB released with the investigation on March 16, 2011, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=76739. 8.4 MB in all. - Witness Statements (item 1, .PDF, 1.8 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40343753&FileExtension=.PDF&FileName=Witness%20Statements-Redacted.PDF - A&P Mechanic Statement (item 2, .PDF, 26 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40343754&FileExtension=.PDF&FileName=A%26P%20Mechanic%20Statement-Redacted.PDF - Witness Statements to SD Highway Patrol (item 3, .PDF, 202 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40344989&FileExtension=.PDF&FileName=Witness%20Statements%20to%20SD%20Highway%20Patrol-Redacted.PDF - Pilot Logbook Entries (item 4, .PDF, 2.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40343755&FileExtension=.PDF&FileName=Pilot%20Logbook%20Entries-Redacted.PDF - Aircraft Logbook Entries (item 5, .PDF, 983 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40343756&FileExtension=.PDF&FileName=Aircraft%20Logbook%20Entries-Redacted.PDF - NTSB Record of Memorandum - Rotec Inspection (item 6, .PDF, 51 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40345012&FileExtension=.PDF&FileName=NTSB%20Record%20of%20Memorandum%20-%20Rotec%20Inspection-Master.PDF - Release of Aircraft Wreckage, NTSB Form 6120.15 (item 7, .PDF, 161 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40344990&FileExtension=.PDF&FileName=Release%20of%20Aircraft%20Wreckage,%20NTSB%20Form%206120.15-Redacted.PDF - A&P Mechanic Note to NTSB IIC (item 8, .PDF, 9 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40343760&FileExtension=.PDF&FileName=A%26P%20Mechanic%20Note%20to%20NTSB%20IIC-Redacted.PDF - Toxicological Report (item 9, .PDF, 36 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40343761&FileExtension=.PDF&FileName=Toxicological%20Report-Redacted.PDF - CEN10LA429 Photo Log (7 embedded photos) (item 10, .PDF, 2.9 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40344741&FileExtension=.PDF&FileName=CEN10LA429%20Photo%20Log%20(7%20embedded%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.