# NTSB WPR22LA324: Champion 7GCBA, N9512S, Athol, ID, August 23, 2022 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 3 · Limited · Final report - Date: August 23, 2022, 09:30 local (16:30 UTC) - Place: Athol, ID - Coordinates: 47.95681, -116.67741 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=47.9568&lon=-116.6774&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing-landing roll: Sys/Comp malf/fail (non-power)](https://openairdocs.org/ntsb-events/330) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Western Pacific Region - Parties: FAA - NTSB case key (mKey): 105834 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR22LA324 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/105834/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=105834 - Page: https://openairdocs.org/ntsb/WPR22LA324 ## Probable cause The failure of the right brake due to a disconnected master cylinder piston rod, which led to the departure of the airplane from the runway surface. Contributing to the accident was the mechanic’s failure to adequately inspect the connection between the piston rod and rudder pedal. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Landing gear system: landing gear brakes system](https://openairdocs.org/ntsb-findings/01023240): Aircraft › Aircraft systems · Inoperative (probable cause); cases with it: [Champion 7GCBA, 1 case](https://openairdocs.org/ntsb-findings/01023240/cases.md?model=21101PH), [All aircraft, 92 cases](https://openairdocs.org/ntsb-findings/01023240/cases.md) - [Inspection: scheduled/routine inspection](https://openairdocs.org/ntsb-findings/02061520): Personnel issues › Task performance · Maintenance personnel (probable cause); cases with it: [Champion 7GCBA, 1 case](https://openairdocs.org/ntsb-findings/02061520/cases.md?model=21101PH), [All aircraft, 167 cases](https://openairdocs.org/ntsb-findings/02061520/cases.md) - [Landing gear system: master cylinder/brake valve](https://openairdocs.org/ntsb-findings/01023243): Aircraft › Aircraft systems · Inadequate inspection (probable cause); cases with it: [Champion 7GCBA, 1 case](https://openairdocs.org/ntsb-findings/01023243/cases.md?model=21101PH), [All aircraft, 21 cases](https://openairdocs.org/ntsb-findings/01023243/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Landing-landing roll: Sys/Comp malf/fail (non-power)](https://openairdocs.org/ntsb-events/330) (defining event); cases with it: [Champion 7GCBA, 1 case](https://openairdocs.org/ntsb-events/330/sequence.md?model=21101PH), [All aircraft, 994 cases](https://openairdocs.org/ntsb-events/330/sequence.md) - [Landing-landing roll: Runway excursion](https://openairdocs.org/ntsb-events/300); cases with it: [Champion 7GCBA, 1 case](https://openairdocs.org/ntsb-events/300/sequence.md?model=21101PH), [All aircraft, 3,643 cases](https://openairdocs.org/ntsb-events/300/sequence.md) ## Analysis The pilot of the tailwheel-equipped airplane reported that the accident flight was uneventful from takeoff to touchdown. However, during the landing roll, the right brake was inoperative, causing the airplane to veer to the left and off the runway surface into a ditch, which resulted in the right main landing gear collapsing and the right wing impacting terrain. A postaccident examination of the airplane revealed that the right brake master cylinder piston rod had disconnected from the right rudder pedal attach point, and that the cotter pin was missing from the clevis pin. The airplane had undergone a conversion to a hydraulic toe brake rudder assembly about 3 years before the accident. However, the investigation was unable to determine, from the available evidence for this accident investigation, if the cotter pin was not installed, improperly installed, or subsequently damaged. The airplane’s an annual inspection was accomplished 12 days and about 1.3 flight hours before the accident. The mechanic who performed the inspection stated that he inspected the right brake system but did not recall or notice if the cotter pin was installed in the clevis pin. Given the short interval between the inspection and the accident, it is likely that the mechanic failed to adequately inspect the connection of the right rudder pedal to its brake system. ## Factual narrative On August 23, 2022, about 0930 Pacific daylight time, a Champion 7GCBA airplane, N9512S, was substantially damaged when it was involved in an accident near Athol, Idaho. The pilot and passenger were not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot reported that the first flight of the day in the tailwheel airplane was uneventful. The second (accident) flight was also uneventful from takeoff to touchdown; during the landing roll, the right brake was inoperative, which resulted in the airplane veering to the left and off the runway surface into a ditch. The right main landing gear then collapsed, which caused the right wing to impact terrain. Postaccident examination of the airplane by a Federal Aviation Administration inspector revealed that right brake master cylinder piston rod had disconnected from the right rudder pedal assembly, and that the cotter pin was missing from the clevis pin that connected it. The clevis pin was located under the right-side floorboard. Minor wear and markings on the clevis pin cad plating were consistent with the pin being installed; no wear or markings were noted in the cotter pin hole. The cotter pin was not located. The left pedal was properly connected with a cotter pin. The airplane had undergone a conversion to a hydraulic toe brake rudder assembly in October 2019. According to the pilot, the airplane had flown about 12 hours since the conversion. The airplane’s annual inspection was accomplished 12 days and about 1.3 hours (tachometer time) before the accident. The mechanic who performed the inspection stated that he inspected the right brake system and did not recall or notice if a cotter pin was installed in the clevis pin. The mechanic further stated that, if he had noticed a missing or bad cotter pin, he would have replaced it. ## Aircraft - Registration: [N9512S](https://openairdocs.org/aircraft/N9512S), registered now, S/N 7GCBA21, built 1965 (OpenAirDocs) - Reported make and model: CHAMPION 7GCBA - Registry model: [Champion 7GCBA](https://openairdocs.org/model/champion-7gcba) (registry code 21101PH) (OpenAirDocs) - Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 7GCBA21 - Year built: 1965 - Airframe hours: 1313.27 - Engines: LYCOMING O-320 SERIES 150 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Aerobatic; Standard, Normal - Last inspection: Annual, August 11, 2022 - Departed: ID05, Athol, ID - Airport: ID05, Hackney Airpark, runway 21, 3,500 × 150 ft, grass/turf - Equipment: Video recording device, Handheld GPS ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 59; injuries: none; airline transport; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, without waivers/limitations; last flight review July 11, 2022; seat: front; restraint: 4-point; flight hours: 18,000 total, 200 in this make and model, 6,000 as pilot in command, 100 in the last 90 days, 2 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 73 °F, dew point 54 °F - Altimeter: 30.04 inHg - Observed at: KCOE, 13 nm away - METAR: KCOE 231656Z AUTO VRB03KT 10SM CLR 23/12 A3004 RMK AO2 SLP173 T02280122 PNO $ ## 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 20220823014989A](https://openairdocs.org/incident/20220823014989A), Aug 23, 2022: Champion 7GCBA, Athol, ID, Substantial damage. After landing on runway 21 and ID05 on roll-out at 30 mph pilot applied brakes and RH brake had not response. With LH brake on the aircraft veered hard left… ## Docket (7 files) The files NTSB released with the investigation on May 2, 2024, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=105834. 14.1 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 9 pages, 7.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=14827821&FileExtension=pdf&FileName=NTSB%206120_Redacted-Rel.pdf - Memorandum for record (item 2, PDF, 3 pages, 119 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=14827488&FileExtension=pdf&FileName=WPR22LA324%20Memorandum%20For%20Record%20Final-Rel.pdf - Annual logbook excerpts (item 3, PDF, 2 pages, 3.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=14827405&FileExtension=pdf&FileName=Annual%20entry_Redacted-Rel.pdf - STC logbook entry (item 4, PDF, 1 page, 791 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=14829067&FileExtension=pdf&FileName=Logbook%20Excerpt%20for%20STC_Redacted-Rel.pdf - STC (item 5, PDF, 3 pages, 1.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=14827498&FileExtension=pdf&FileName=STC%20Final_Redacted-Rel.pdf - Release of aircraft wreckage, NTSB form 6120.15 (item 6, PDF, 1 page, 898 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=14833939&FileExtension=pdf&FileName=Wrecakge%20Release%20Form_Redacted-Rel.pdf - Accident pictures (item 7, PDF, 2 pages, 526 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=14828078&FileExtension=pdf&FileName=WPR22LA324%20Accident%20Pictures-Rel.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.