# NTSB DEN01LA026: Sukhoi SU-29, N55SU, Longmont, CO, August 14, 2000 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: August 14, 2000, 10:30 local (16:30 UTC) - Place: Longmont, CO - Location: 40.1682° N, 105.1005° W: Placed by OpenAirDocs: center of Longmont, CO, within about 6 miles (OpenAirDocs) - Nearby events: https://openairdocs.org/map.md?lat=40.1682&lon=-105.1005&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report November 25, 2003 - Report: Approved by Office Director - NTSB case key (mKey): 50783 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN01LA026 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/50783/pdf - Page: https://openairdocs.org/ntsb/DEN01LA026 ## Probable cause The inadequate structural materials (American manufactured verses original Russian materials) used during a major repair. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Airframe/component/system failure/malfunction, landing - flare/touchdown - miscellaneous,airframe - bent - material defect(inadequate quality of material), other maintenance personnel (cause) - maintenance,major repair - inadequate, other maintenance personnel (cause) - Loss of control - on ground/water, landing - roll - directional control - not possible ## Analysis During landing, the airplane exited the right side of the runway and the left wing impacted the ground. The pilot taxied to his hangar. Postaccident examination was delayed several months (until December 11, 2000) to allow Sukhoi representatives to assess the damage. They determined that several structural tubes just aft of the engine firewall needed to be replaced. The damaged area of the fuselage was where the main landing gear attached to the fuselage. It could not be determined if the structural damage that occurred on August 14, 2000, was the result of one landing or progressive damage from several landings. The tubes that needed replacement following the August 14, 2000, event had been previously damaged (bent or broken) during an accident on May 11, 1996. At that time, several unsuccessful attempts were made to acquire Russian materials and technical assistance. The decision was made to perform the repairs using American materials. According to the Sukhoi representatives, the American tubing and welding rods were 'incompatible' with the original Russian materials. ## Factual narrative On August 15, 2000, at approximately 1030 mountain daylight time, a Sukhoi SU-29, N55SU, was substantially damaged during a landing at Vance Brand Airport, Longmont, Colorado. The airline transport pilot, the sole occupant onboard, was not injured. The pilot/owner was operating the aircraft under Title 14 CFR Part 91. Visual meteorological conditions prevailed for the local flight that originated approximately 30 minutes before the accident. The pilot had not filed a flight plan. The pilot said that the purpose of the flight was to practice aerobatic maneuvers. On his return to the airport, the landing was "uneventful, in fact remarkably smooth." The pilot said that shortly after touchdown, the airplane swerved to the right and exited the runway. He said that the left wing "slightly touched the grass." He continued to taxi to his hangar. Postaccident examination was delayed several months (until December 11, 2000) to allow Sukhoi representatives to assess the damage. They determined that several structural tubes just aft of the engine firewall needed to be replaced. The damaged area of tubing was where the main landing gear attached to the fuselage. It could not be determined if the structural damage that occurred on August 15, 2000, was the result of one landing or progressive damage from several landings. The tubes that needed replacement following the August 15, 2000, event had been previously damaged (bent or broken) during an accident on May 11, 1996. At that time, several unsuccessful attempts were made to acquire Russian materials and technical assistance. The decision was made to perform the repairs using American materials. According to the Sukhoi representatives, the American tubing and welding rods were "incompatible" with the original Russian materials. ## Aircraft - Registration: [N55SU](https://openairdocs.org/deregistered/N55SU-2014-10-09), registration cancelled 2014-10-09, S/N 73-05 (OpenAirDocs) - Reported make and model: Sukhoi SU-29 - Registry model: [Sukhoi SU-29](https://openairdocs.org/model/sukhoi-su-29) (registry code 9850103) (OpenAirDocs) - Category: Airplane - Serial number: 73-05 - Airframe hours: 446 - Engines: Vendeneyev M-14-P 360 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Richard A. Basiliere - Airworthiness certificate: Special, Experimental (Special) - Last inspection: AAIP, February 5, 2000, 66 hours before - Departed: 2V2 - Airport: 2V2, Vance Brand Airport, runway 29, 4,800 × 75 ft, concrete ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; airline transport; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 2, valid medical--no waivers/lim.; flight hours: 8,775 total, 75 in this make and model, 60 in the last 90 days, 32 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 300° at 8 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 75 °F, dew point 45 °F ## Other investigations on N55SU (1) 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. - [NTSB FTW96FA208](https://openairdocs.org/ntsb/FTW96FA208), May 11, 1996: Sukhoi SU-29 (N55SU), Englewood, CO, minor damage, 1 fatal. Probable cause: failure of the pilot of the RV-4, N44AZ, to comply with an ATC clearance by landing on the wrong runway, and the failure of the pilot of the SU-29, N55SU, to maintain an adequate visual lookout.… 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.