# NTSB WPR24LA192: SIAI Marchetti SM. 1019, N992BB, Twin Bridges, MT, May 19, 2024 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 4 · Limited · Final report - Date: May 19, 2024, 11:20 local (17:20 UTC) - Place: Twin Bridges, MT - Coordinates: 45.534722, -112.29888 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=45.5347&lon=-112.2989&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 4 - Basic report with no Prelim publish - NTSB office: Western Pacific Region - Parties: FAA - NTSB case key (mKey): 194456 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR24LA192 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/194456/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=194456 - Page: https://openairdocs.org/ntsb/WPR24LA192 ## Probable cause The binding of the parking brake cable, which resulted in un-commanded brake application during the landing roll and subsequent nose over. ## 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 · Malfunction (probable cause); cases with it: [Siai-Marchetti SM 1019, 1 case](https://openairdocs.org/ntsb-findings/01023240/cases.md?model=8121215), [All aircraft, 92 cases](https://openairdocs.org/ntsb-findings/01023240/cases.md) - [Aircraft capability: braking capability](https://openairdocs.org/ntsb-findings/01061050): Aircraft › Aircraft oper/perf/capability · Malfunction (probable cause); cases with it: [Siai-Marchetti SM 1019, 1 case](https://openairdocs.org/ntsb-findings/01061050/cases.md?model=8121215), [All aircraft, 57 cases](https://openairdocs.org/ntsb-findings/01061050/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: [Siai-Marchetti SM 1019, 1 case](https://openairdocs.org/ntsb-events/330/sequence.md?model=8121215), [All aircraft, 994 cases](https://openairdocs.org/ntsb-events/330/sequence.md) - [Landing-landing roll: Nose over/nose down](https://openairdocs.org/ntsb-events/096); cases with it: [Siai-Marchetti SM 1019, 2 cases](https://openairdocs.org/ntsb-events/096/sequence.md?model=8121215), [All aircraft, 2,287 cases](https://openairdocs.org/ntsb-events/096/sequence.md) ## Analysis The pilot of the tailwheel-equipped airplane reported that shortly after touchdown, during the landing roll, the tail began to rise, and the airplane subsequently nosed over. Skid marks on the runway were consistent with the right main wheel skidding during landing. The airplane sustained substantial damage to the left wing. A postaccident examination of the airplane revealed that the parking brake cable was binding. This binding prevented full travel of the parking brake to the “OFF” position and not fully release, which resulted in un-commanded braking application during landing roll. ## Aircraft - Registration: [N992BB](https://openairdocs.org/aircraft/N992BB), registered now, S/N 012, built 1976 (OpenAirDocs) - Reported make and model: SIAI MARCHETTI SM. 1019 - Registry model: [Siai-Marchetti SM 1019](https://openairdocs.org/model/siai-marchetti-sm-1019) (registry code 8121215) (OpenAirDocs) - Registry engine: [Allison 250-B17E](https://openairdocs.org/engine/allison-250-b17e) (registry code 03069, turbo-prop) (OpenAirDocs) - Category: Airplane - Serial number: 012 - Year built: 1976 - Airframe hours: 2765.35 - Engines: Rolls Royce 250B-17E 420 horsepower turbo prop - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Ruby Valley Aviation LC - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Condition, January 15, 2024, 3.6 hours before - Departed: EKS, Ennis, MT - Destination: Same as departure - Airport: RVF, Ruby Valley Field Airport, runway 17, 3,000 × 100 ft, gravel - Equipment: Electronic primary flight display, Electronic multifunction display, ADS-B, Stall warning system ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 72; injuries: none; private; airplane ratings: single-engine sea, single-engine land, multi-engine land; instrument ratings: airplane; medical: class 3, waiver time limited special; last flight review September 20, 2023; seat: front; restraint: 4-point; flight hours: 8,306 total, 460 in this make and model, 8,246 as pilot in command, 39 in the last 90 days, 20.7 in the last 30 days, 2 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 270° at 9 knots, gusting 22 - Visibility: 10 statute miles - Lowest ceiling: 6,000 ft broken - Temperature: 46 °F, dew point 21 °F - Altimeter: 29.91 inHg - Observed at: KWYS, 71 nm away - METAR: METAR KWYS 191755Z AUTO 27009G22KT 240V320 10SM BKN060 08/M06 A2991 RMK AO2 ## 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 20240519005839A](https://openairdocs.org/incident/20240519005839A), May 19, 2024: Siai-Marchetti SM 1019, Twin Bridges, MT, Substantial damage. Following this investigation, I did not identify any regulatory violations or pilot proficiency issues as causal factors that contributed to this accident. Per… ## Docket (3 files) The files NTSB released with the investigation on February 11, 2025, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=194456. 4.9 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 10 pages, 4.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=17482095&FileExtension=pdf&FileName=6120_Orignal_Redacted-Rel.pdf - Photos (item 2, PDF, 4 pages, 3 photos, 830 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=17406110&FileExtension=pdf&FileName=Photos(Docket)-Rel.pdf - Memorandum for record a�� FAA email correspondence (item 3, PDF, 1 page, 52 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=17519409&FileExtension=pdf&FileName=WPR24LA192%20Memorandum%20for%20Record-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.