# NTSB ATL04CA154: Glassic Composites SQ-2000 XL, N10736, Dayton, TN, July 10, 2004 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: July 10, 2004, 11:35 local (15:35 UTC) - Place: Dayton, TN - Coordinates: 35.486389, -84.931114 - Nearby events: https://openairdocs.org/map.md?lat=35.4864&lon=-84.9311&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report October 28, 2004 - Report: Approved by Office Director - Parties: Nashville FSDO - NTSB case key (mKey): 59921 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ATL04CA154 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/59921/pdf - Page: https://openairdocs.org/ntsb/ATL04CA154 ## Probable cause The pilot's failure to maintain directional control during landing roll, which resulted in a ground loop and the subsequent collapse of the landing gear. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Airframe/component/system failure/malfunction, approach - vfr pattern - base leg/base to final - Loss of control - on ground/water, landing - roll - directional control - not maintained, pilot in command (cause) - landing gear,gear locking mechanism - overload - ground loop/swerve - inadvertent, pilot in command (cause) - Gear collapsed, landing - roll - On ground/water collision with object, landing - roll - object - fence ## Analysis According to the pilot, the purpose of the flight was to practice takeoffs and landings in the traffic pattern. The pilot stated that he reduced engine power and extended the landing gear on the base leg and heard a "pop" noise. He stated that he initially though that the noise might have been a backfire of the engine when he reduced power. He stated that he observed the gear pump indication of cycle complete, a three-green indication of gear extended and locked, and visually observed the left landing gear extended, so he decided to proceed with the approach. He stated that on the landing roll approximately 200-300 yards after touchdown, the left wing began to descend, and he raised the left wing to maintain level, but it slowly made contact with the runway. He stated that he did not apply power for a go-around. He stated directional control of the airplane was lost and the airplane departed the runway surface to the left, and ground looped. The pilot stated that the right main landing gear then collided with a boulder, and the right main and nose landing gear collapsed, and the airplane skidded in the grass on its belly 400-500 feet and collided with a fence. The post-accident examination of the airplane wreckage revealed that the nose and the main landing gear were collapsed and bent and the rod. Further examination revealed that the end bearing head of the hydraulic actuator of the left main landing gear was found broken at the upper neck. The three-bladed wooden propeller was sheared on all blades. The engine appeared to be intact with no visible external damage and the internal engine components rotated freely. Further examination of the rod end bearing head revealed that the fracture was a bending overload failure. ## Factual narrative On July 10, 2004, at 1135 eastern daylight time, a Glassic Composites SQ-2000 experimental airplane, N10736, veered off runway 21 and collided with a fence at Mark Anton Airport, Dayton, Tennessee. The local flight was conducted under Title 14 CFR Part 91, and visual flight rules. Visual meteorological conditions prevailed at the time of the accident and no flight plan was filed. The pilot was not injured and the airplane sustained substantial damage. The flight departed Mark Anton Airport, Dayton, Tennessee at 1130. According to the pilot, the purpose of the flight was to practice takeoffs and landings in the traffic pattern. The pilot stated that he reduced engine power and extended the landing gear on the base leg and heard a "pop" noise. He stated that he initially though that the noise might have been a backfire of the engine when he reduced power. He stated that he observed the gear pump indication of cycle complete, a three-green indication of gear extended and locked, and visually observed the left landing gear extended, so he decided to proceed with the approach. He stated that on the landing roll approximately 200-300 yards after touchdown, the left wing began to descend, and he raised the left wing to maintain level, but it slowly made contact with the runway. He stated that he did not apply power for a go-around. He stated directional control of the airplane was lost and the airplane departed the runway surface to the left, and ground looped. The pilot stated that the right main landing gear then collided with a boulder, and the right main and nose landing gear collapsed, and the airplane skidded in the grass on its belly 400-500 feet and collided with a fence. The post-accident examination of the airplane wreckage revealed that the nose and the main landing gear were collapsed and bent and the rod. Further examination revealed that the end bearing head of the hydraulic actuator of the left main landing gear was found broken at the upper neck. The three-bladed wooden propeller was sheared on all blades. The engine appeared to be intact with no visible external damage and the internal engine components rotated freely. Further examination of the rod end bearing head revealed that the fracture was a bending overload failure. According to the airport manager, there were tire marks that began about 1/4 to 1/3 from the runway threshold of 21. She said that the tire marks looked as though they "skipped" and extended approximately 100 feet in a curving profile to the left side of the runway in the direction where the airplane departed the runway surface. She further stated that propeller debris had to be removed from the runway. ## Aircraft - Registration: [N10736](https://openairdocs.org/deregistered/N10736-2017-07-14), registration cancelled 2017-07-14, S/N GCSQ-0001, built 1997 (OpenAirDocs) - Reported make and model: Glassic Composites SQ-2000 XL - Registry model: [Thompson K/Montgomery S K SQ-2000](https://openairdocs.org/model/thompson-k-montgomery-s-k-sq-2000) (registry code 05603OU) (OpenAirDocs) - Registry engine: [Lycoming I0360 SER A&C](https://openairdocs.org/engine/lycoming-i0360-ser-a-c) (registry code 41511, reciprocating) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: GC-0001 - Airframe hours: 386 - Engines: Lycoming 360 200 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Stanley Keith Montgomery - Registered owner: William Keith Register - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Annual, May 5, 2004, 8 hours before - Departed: 2A0, Dayton, TN - Destination: 2A0, Dayton, TN - Airport: 2A0, Mark Anton Airport, runway 21, 5,000 × 75 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 49; injuries: none; commercial; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; last flight review April 29, 2004; seat: left; flight hours: 2,085 total, 386 in this make and model, 18 in the last 90 days, 10 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 260° at 6 knots - Visibility: 10 statute miles - Lowest ceiling: 10,000 ft broken - Temperature: 88 °F, dew point 70 °F - Altimeter: 30.18 inHg - Observed at: kCHA, 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 20040710018349A](https://openairdocs.org/incident/20040710018349A), Jul 10, 2004: Amtr SQ2000, Dayton, TN, Substantial damage. (-23) On landing, the rod in bearing on the right landing gear failed, and the right landing gear collapsed. Departed the runway and ran into a fence resulting… 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.