# NTSB CEN10LA526: Thompson Kolb Twinstar Mark, N408K, Elkhart, IN, September 8, 2010 - Type: NTSB accident investigation - Classification: Accident · Fatal · Limited investigation · Final report - Date: September 8, 2010, 19:58 local (23:58 UTC) - Place: Elkhart, IN - Coordinates: 41.707778, -85.999725 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=41.7078&lon=-85.9997&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing: Loss of control in flight](https://openairdocs.org/ntsb-events/240) - Highest injury: Fatal - Injuries: 1 fatal - Status: Completed, report July 21, 2011 - Report: Approved by Office Director - NTSB office: Central Region - Parties: FAA-SBN-FSDO - NTSB case key (mKey): 77236 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN10LA526 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/77236/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=77236 - Page: https://openairdocs.org/ntsb/CEN10LA526 ## Probable cause The pilot's failure to maintain control of the airplane during the landing approach. ## 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: [Thompson D S KOLB TWINSTARMARKIII, 1 case](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=05629PK), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Landing: Loss of control in flight](https://openairdocs.org/ntsb-events/240) (defining event); cases with it: [Thompson D S KOLB TWINSTARMARKIII, 1 case](https://openairdocs.org/ntsb-events/240/sequence.md?model=05629PK), [All aircraft, 5,002 cases](https://openairdocs.org/ntsb-events/240/sequence.md) - [Uncontrolled descent: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Thompson D S KOLB TWINSTARMARKIII, 1 case](https://openairdocs.org/ntsb-events/470/sequence.md?model=05629PK), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The accident occurred during the amateur-built airplane's first flight. According to the pilot, the purpose of the flight was to determine the stall speed and handling characteristics of the airplane during the flight. After departure, the pilot circled the airport at an altitude of about 3,000 feet, and then requested a return for landing with air traffic control. A video of the accident showed the airplane in a steep descent toward a grassy area between the runway and taxiway. As the airplane neared the ground, the nose of the airplane oscillated pitching up, down, and up again prior to the nose dropping and the airplane impacting the ground. A witness reported the engine sounded normal during the flight and while the airplane was on final approach. A postaccident examination of the airframe did not reveal any failure or malfunction that would have resulted in the loss of control. ## Factual narrative HISTORY OF FLIGHT On September 8, 2010, at 1958 eastern daylight time, an amateur-built Thompson Kolb Twinstar Mark III, N408K, impacted the terrain following a loss of control while landing on runway 36 at the Elkhart Municipal Airport (EKM), Elkhart, Indiana. The pilot was fatally injured and the airplane was substantially damaged. The flight was being conducted under the provisions of 14 Code of Federal Regulations Part 91. The local flight was operating in visual meteorological conditions without a flight plan. The flight departed from EKM about 1938. The accident occurred on the first flight following completion of the airplane's construction. According to personnel at the EKM air traffic control tower, the pilot went to the control tower to speak with the controllers. He stated he was going to make the airplane’s first flight and that after takeoff he wanted to orbit the airport at 3,000 feet so he could get a feel for the airplane. He stated he needed to figure out the stall speed and handling characteristics of the airplane. There were several witnesses who saw the airplane during the flight. An air traffic controller stated the airplane took off and circled the airport for 10 to 12 minutes. The pilot then radioed that he was ready to return to land. The controller cleared the pilot for the option to land, go-around, make a low pass, a touch and go, or a stop and go. He stated he was not sure if the airplane ever touched down on the runway, but he saw the airplane nose down and impact the ground off the side of the runway. Another witness, a pilot, reported seeing the airplane takeoff. He stated the airplane climbed to an altitude of 50 feet above the runway where it leveled off and flew parallel to the runway prior to climbing. The airplane then climbed to an altitude he estimated to be about 2,500 feet. The airplane circled the airport about 3 times before turning onto final approach for runway 36. The witness stated the airplane made a “very steep descent” onto final approach. He then lost sight of the airplane as it traveled behind the trees. The witnesses reported the engine sounded normal during the flight and while the airplane was on final approach. The accident portion of the flight was captured on video. The video showed the airplane descending at what appeared to be a steep angle toward the airport in front of a tree line. The airplane appeared to be lined up with the grass between the runway and the taxiway, and not with the runway. As the airplane neared the ground, the nose of the airplane pitched up, down, and up again prior to the nose dropping and the airplane impacting the ground. PERSONNEL INFORMATION The pilot, age 48, held a sport pilot certificate, issued on August 31, 2009. The pilot did not hold a Federal Aviation Administration (FAA) medical certificate. The pilot’s logbook indicated that as of September 5, 2010, the pilot had accumulated a total of 76 hours of flight time. The pilot had logged about 49 hours inan Allegro light sport airplane (LSA). The pilot had a total of 8 hours of dual flight instruction in a Kolb Twinstar Mark III LSA, having logged 3 hours in May 2005 and 5 hours in June 2010. The pilot had not logged any pilot-in-command time in Kolb Twinstar Mark III airplanes. AIRCRAFT INFORMATION The airplane was an amateur-built Kolb Twinstar Mark III, serial number M3X6-4-00083, which was built and owned by the accident pilot. The Twinstar Mark III is a two-place tailwheel configured airplane designed with short takeoff and landing (STOL) capabilities. The airplane’s tail and wings are designed to fold for transporting and storage of the airplane. The wings are strut-braced, fabric covered, with steel tubing and aluminum sub-structure. The flight controls are operated with control cables and push/pull tubes. The airplane was powered by a 100 horsepower, pusher mounted Rotax 912. The engine is mounted on the aft portion of the fuselage and partially above the height of the wing. The airplane met the limitations to be operated as a light sport aircraft. The aircraft registration was issued to the pilot on April 5, 2010. An Experimental category Special Airworthiness Certificate and the Experimental Operating Limitations were issued on July 24, 2010. The accident occurred during the first flight of the airplane. A friend of the pilot who was familiar with Kolb Twinstar Mark III airplanes stated that because the pusher engine is mounted high, these airplanes tend to nose up when engine power is removed and to nose down when power is added. METEOROLOGICAL INFORMATION At 1855, the automated weather observing system at EKM, reported wind from 360 degrees at 7 knots, 10 statute miles visibility, clear sky conditions, temperature 17 degrees Celsius, dew point 8 Celsius, and a barometric pressure setting of 30.10 inches of Mercury. WRECKAGE AND IMPACT INFORMATION The airplane impacted a grass field located between runway 36 and the parallel taxiway. The wreckage was located approximately 1,000 feet from the approach end of runway 36 and about 30 feet west of the runway. A review of the video showed the airplane impacted the ground in a nose down, slight right wing low attitude. The airplane then rolled tail over nose prior to coming to rest in an upright position. The instrument panel was pushed back into the cockpit area. The left wing remained attached to the fuselage, and the right wing detached from the fuselage with the wing strut still attached to the wing and fuselage. The tailboom style aft fuselage was fractured near the fuselage. All of the flight control surfaces remained attached to their respective airplane surfaces. Flight control continuity was established from the cockpit to all of the flight controls. All three propeller blades were broken. The engine remained attached to the engine mounts. Examination of the airframe did not reveal any failure/malfunction that would have resulted in the loss of control. MEDICAL AND PATHOLOGICALINFORMATION An autopsy on the pilot was performed on September 9, 2010, at the South Bend Medical Foundation. The autopsy findings included "multiple blunt force injuries." The FAA, Civil Aerospace Medical Institute, conducted toxicological testing on the pilot. The toxicology report stated Amlodipine was detected in the liver and blood, Atropine was detected in the heart and blood, and Diphenhydramine was detected in the liver along with 0.164 (ug/ml, ug/g) detected in the blood. Ibuprofen and Naproxen were also detected in blood. ## Aircraft - Registration: [N408K](https://openairdocs.org/deregistered/N408K-2013-05-15), registration cancelled 2013-05-15, S/N M3X6-4-00083, built 2010 (OpenAirDocs) - Reported make and model: Thompson Kolb Twinstar Mark - Registry model: [Thompson D S KOLB TWINSTARMARKIII](https://openairdocs.org/model/thompson-d-s-kolb-twinstarmarkiii) (registry code 05629PK) (OpenAirDocs) - Registry engine: [Rotax 912ULS series](https://openairdocs.org/engine/rotax-912uls-series) (registry code 55572, 4 cycle) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: M3X6-4-00083 - Airframe hours: 0 - Engines: Rotax 912ULS reciprocating - Damage: Substantial damage - Flight: Flight test, Part 91 - Operator: Donald S. Thompson - Registered owner: Donald S. Thompson - Airworthiness certificate: Special, Experimental (Special) - Last inspection: July 24, 2010 - Departed: EKM, Elkhart, IN - Destination: EKM, Elkhart, IN - Airport: EKM, Elkhart Municipal Airport, runway 36, 4,001 × 75 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 48; injuries: fatal; sport pilot; seat: left; toxicology performed; flight hours: 76 total, 8 in this make and model, 28 as pilot in command, 2 in the last 90 days, 1 in the last 30 days ## Weather - Conditions: Visual (VMC), Dusk - Wind: 360° at 7 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 63 °F, dew point 46 °F - Altimeter: 30.10 inHg - Observed at: EKM ## 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 20100908050419A](https://openairdocs.org/incident/20100908050419A), Sep 8, 2010: Thompson D KOLB TWINST, Elkhart, IN, Destroyed, 1 fatal. On September 08,2010, at approximately 1930 local time [privacy data omitted], a certificated light sport aircraft pilot, took off from Elkhart Municipal… ## Docket (14 files) The files NTSB released with the investigation on June 8, 2011, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=77236. 7.7 MB in all. - Record of Conversations (item 1, .PDF, 68 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40348646&FileExtension=.PDF&FileName=Record%20of%20Conversations-Master.PDF - Elkhart Police Department Report (item 2, .PDF, 1.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40346265&FileExtension=.PDF&FileName=Elkhart%20Police%20Department%20Report-Redacted.PDF - Toxicological Report (item 3, .PDF, 79 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40346267&FileExtension=.PDF&FileName=Toxicological%20Report-Redacted.PDF - Accident Video Information (item 4, .PDF, 9 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40348212&FileExtension=.PDF&FileName=Accident%20Video%20Information-Master.PDF - Photo 01. Main Wreckage (item 5, .PDF, 621 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40347645&FileExtension=.PDF&FileName=Photo%2001.%20Main%20Wreckage-Master.PDF - Photo 02. Main Wreckage. (item 6, .PDF, 677 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40347729&FileExtension=.PDF&FileName=Photo%2002.%20%20Main%20Wreckage.-Master.PDF - Photo 03. Aft View of Main Wreckage. (item 7, .PDF, 370 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40347657&FileExtension=.PDF&FileName=Photo%2003.%20Aft%20View%20of%20Main%20Wreckage.-Master.PDF - Photo 04. Right Side View of Main Wreckage. (item 8, .PDF, 633 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40347658&FileExtension=.PDF&FileName=Photo%2004.%20Right%20Side%20View%20of%20Main%20Wreckage.-Master.PDF - Photo 05. Front View of Main Wreckage. (item 9, .PDF, 633 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40347720&FileExtension=.PDF&FileName=Photo%2005.%20Front%20View%20of%20Main%20Wreckage.-Master.PDF - Photo 06. Close Up View of Cockpit. (item 10, .PDF, 810 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40347722&FileExtension=.PDF&FileName=Photo%2006.%20Close%20Up%20View%20of%20Cockpit.-Master.PDF - Photo 07. Aft View of Main Wreckage. (item 11, .PDF, 714 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40347723&FileExtension=.PDF&FileName=Photo%2007.%20Aft%20View%20of%20Main%20Wreckage.-Master.PDF - Photo 08. Empennage (item 12, .PDF, 594 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40347725&FileExtension=.PDF&FileName=Photo%2008.%20Empennage-Master.PDF - Photo 09. Close up View of the Propeller and Engine. (item 13, .PDF, 704 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40347728&FileExtension=.PDF&FileName=Photo%2009.%20Close%20up%20View%20of%20the%20Propeller%20and%20Engine.-Master.PDF - Photo 10. Slice in Tailboom. (item 14, .PDF, 782 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40347727&FileExtension=.PDF&FileName=Photo%2010.%20Slice%20in%20Tailboom.-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.