# NTSB LAX02LA226: Ayres S2R-T34, N4020Y, Firebaugh, CA, July 13, 2002 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: July 12, 2002, 20:30 local (Jul 13, 2002, 03:30 UTC) - Place: Firebaugh, CA - Coordinates: 36.849998, -120.449996 - Nearby events: https://openairdocs.org/map.md?lat=36.8500&lon=-120.4500&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report March 2, 2004 - Report: Approved by Office Director - Parties: Federal Aviation Administration - NTSB case key (mKey): 55209 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX02LA226 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/55209/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=55209 - Page: https://openairdocs.org/ntsb/LAX02LA226 ## Probable cause The overload fracture and separation of the left main gear strut assembly due the left landing gear's encounter with a chuck hole in the private airstrip's asphalt pavement. A factor in the accident was the inadequate maintenance of the airstrip's surface. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Airframe/component/system failure/malfunction, takeoff - roll/run - airport facilities,runway/landing area condition - rough/uneven (cause) - runway maintenance - inadequate, other person (contributing factor) - landing gear,main gear strut - fractured (cause) - landing gear,main gear - separation (cause) - On ground/water encounter with terrain/water, takeoff - roll/run - terrain condition - ditch ## Analysis The airplane sustained a separated left main landing gear during the takeoff ground roll from a private farm airstrip. After the landing gear separated from the airplane, the airplane veered off of the runway and came to rest in a ditch. An FAA airworthiness inspector examined the airplane. He reported that the ear that secures the left main gear strut to the fuselage structure had fractured and separated, allowing the left gear strut to separate from the fuselage. The inspector examined the 30-foot-wide airstrip in the area used by the pilot for the takeoff ground roll. He located a chuck hole in the asphalt pavement that was 15 feet long by 3 feet wide and that had a maximum depth of 3 inches. At the northern end of the chuck hole (closest to the airplane point of rest), a 2.5-inch-deep lip was noted in the hole wall. Marks and transfers consistent with the landing gear and the fuselage contact to the pavement were noted just beyond this chuck hole. ## Factual narrative On July 12, 2002, at 2030 Pacific daylight time, an Ayers S2R-T34, N4020Y, sustained a separated left main landing gear during the takeoff ground roll at the Newman Ranch Strip, 5 miles east of Firebaugh, California. After the landing gear separated from the airplane, the airplane veered off the runway. The airplane, owned and operated by Thiel Air Care under the provisions of 14 CFR Part 137, sustained substantial damage. The commercial pilot, the sole occupant, was not injured. Visual meteorological conditions prevailed for the local area aerial application flight that was originating at the time. No flight plan had been filed. In a written statement submitted by the pilot, he reported that approximately 200 feet into the takeoff roll, the left main gear collapsed. The left wing tip and the propeller struck the ground. This was followed by the airplane pivoting to the left and going into a ditch. As the airplane impacted the opposite side of the ditch, the right main gear was forced under the airplane. The airplane came to rest on its belly. The pilot shut the engine down manually. A Federal Aviation Administration airworthiness inspector from the Fresno, California, Flight Standards District Office examined the airplane. He reported that the ear that secures the left main gear strut to the fuselage structure had fractured and separated, allowing the left gear strut to separate from the fuselage. The inspector examined the 30-foot-wide airstrip in the area used by the pilot for the takeoff ground roll. He located a chuck hole in the asphalt pavement that was 15 feet long by 3 feet wide and that had a maximum depth of 3 inches. At the northern end of the chuck hole (closest to the airplane point of rest), a 2.5-inch-deep lip was noted in the hole wall. Marks and transfers consistent with the landing gear and the fuselage contact to the pavement were noted just beyond this chuck hole. ## Aircraft - Registration: [N4020Y](https://openairdocs.org/deregistered/N4020Y-2013-08-13), registration cancelled 2013-08-13, S/N T34-022, built 1980 (OpenAirDocs) - Reported make and model: Ayres S2R-T34 - Registry model: [Ayres S2R-T34](https://openairdocs.org/model/ayres-s2r-t34) (registry code 0970106) (OpenAirDocs) - Registry engine: [Pratt & Whitney Canada PT6A-60A](https://openairdocs.org/engine/pratt-whitney-canada-pt6a-60a) (registry code 52043, turbo-prop) (OpenAirDocs) - Category: Airplane - Serial number: T34-022 - Airframe hours: 1542 - Engines: Pratt & Whitney PT6-34AG 750 horsepower turbo prop - Damage: Substantial damage - Flight: Aerial application, Part 137 - Registered owner: Douglas Thiel - Airworthiness certificate: Special, Restricted (Special) - Last inspection: 100 hour, April 1, 2002, 157 hours before - Departed: PVT, Firebaugh, CA - Airport: PVT, Newman Strip, runway NW, 2,500 × 30 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 47; injuries: none; commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 2, valid medical--no waivers/lim.; last flight review August 30, 2001; seat: center; flight hours: 18,000 total, 12,000 in this make and model, 120 in the last 90 days, 75 in the last 30 days, 9 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 310° at 14 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 93 °F, dew point 59 °F - Altimeter: 29.79 inHg - Observed at: KFAT, 37 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 20020712016179A](https://openairdocs.org/incident/20020712016179A), Jul 12, 2002: Ayres S2RT34NORMAL, Firebaugh, CA, No damage. (.19) On July 12, 2002, at 2030 pacific daylight time, a ayers S2R-T34, N4020Y, sustained a separated left main landing gear during the takeoff ground roll at… ## Docket (2 files) The files NTSB released with the investigation on December 12, 2003, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=55209. 511 KB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 498 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40461721&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Record of Conversation-FAA (item 2, .PDF, 13 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40181040&FileExtension=.PDF&FileName=Record%20of%20Conversation-FAA-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.