# NTSB WPR20LA295: Beech 35, N818S, Three Rivers, CA, September 4, 2020 - Type: NTSB accident investigation - Classification: Accident · Fatal · Class 3 · Limited · Final report - Date: September 4, 2020, 11:48 local (18:48 UTC) - Place: Three Rivers, CA - Coordinates: 36.401943, -118.61333 - Nearby events: https://openairdocs.org/map.md?lat=36.4019&lon=-118.6133&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute-cruise: Controlled flight into terr/obj (CFIT)](https://openairdocs.org/ntsb-events/120) - Highest injury: Fatal - Injuries: 2 fatal - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Western Pacific Region - Parties: FSDO, Textron Aviation - NTSB case key (mKey): 101919 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR20LA295 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/101919/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=101919 - Page: https://openairdocs.org/ntsb/WPR20LA295 ## Probable cause The pilot’s controlled flight into terrain while operating in conditions of reduced visibility due to smoke. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Info processing/decision: decision making/judgment](https://openairdocs.org/ntsb-findings/02041520): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Beech V35B, 5 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md?model=1151548), [All aircraft, 3,098 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md) - [Ceiling/visibility/precip: haze/smoke](https://openairdocs.org/ntsb-findings/03035020): Environmental issues › Conditions/weather/phenomena · Contributed to outcome (probable cause); cases with it: [Beech V35B, 1 case](https://openairdocs.org/ntsb-findings/03035020/cases.md?model=1151548), [All aircraft, 21 cases](https://openairdocs.org/ntsb-findings/03035020/cases.md) - [Performance/control parameters: altitude](https://openairdocs.org/ntsb-findings/01062012): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Beech V35B, 4 cases](https://openairdocs.org/ntsb-findings/01062012/cases.md?model=1151548), [All aircraft, 1,310 cases](https://openairdocs.org/ntsb-findings/01062012/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute-cruise: Other weather encounter](https://openairdocs.org/ntsb-events/400); cases with it: [Beech V35B, 4 cases](https://openairdocs.org/ntsb-events/400/sequence.md?model=1151548), [All aircraft, 1,127 cases](https://openairdocs.org/ntsb-events/400/sequence.md) - [Enroute-cruise: Controlled flight into terr/obj (CFIT)](https://openairdocs.org/ntsb-events/120) (defining event); cases with it: [Beech V35B, 5 cases](https://openairdocs.org/ntsb-events/120/sequence.md?model=1151548), [All aircraft, 1,074 cases](https://openairdocs.org/ntsb-events/120/sequence.md) ## Analysis The pilot and passenger departed on a visual flight rules cross-country flight into an area of reduced visibility due to wildfire smoke. An alert notice was issued when the airplane did not arrive at the destination, and the wreckage was located the following day in mountainous terrain at an elevation about 9,500 ft mean sea level. No anomalies were noted with the airplane during post-accident examination. Impact signatures and wreckage dispersion were consistent with the pilot’s controlled flight into terrain while operating in conditions of reduced visibility due to smoke. ## Factual narrative On September 4, 2020, about 1148 Pacific daylight time, a Beechcraft 35 airplane, N818S, was destroyed when it was involved in an accident near Three Rivers, California. The pilot and passenger sustained fatal injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The Federal Aviation Administration issued an alert notice (ALNOT) for the airplane after family members reported the airplane missing. Radar data depicted a primary target consistent with the accident airplane depart Visalia Municipal Airport (VIS), Visalia, California, about 1125 and fly east on the visual flight rules non-discreet transponder code. The airplane flew toward rising terrain south of Silver City, California, and the last recorded radar target was about 1148. The wreckage was discovered on September 5, 2020, in mountainous terrain at an elevation of approximately 9,500 feet mean sea level (msl), on top of a small plateau with large pine trees and large boulders. The airplane was destroyed, and portions of the wreckage were consumed by post impact fire. The wreckage was dispersed along a path about 160 ft long. The wreckage was recovered and examined at a secure location. The wreckage was highly fragmented and thermally damaged. The cabin from the cockpit seats to the firewall were mostly consumed by fire. The side and upper cabin skins from the baggage compartment forward were consumed by fire. The wings were fractured into multiple segments. The majority of the right wing was consumed by fire. Portions of the wing spar remained. The wing tip fuel tanks sustained thermal damage. The stabilizers and elevators were impact separated from the tail. The inboard portion of the left stabilizer exhibited an 18-inch circular tree impact impression perpendicular to the stabilizer chord line. The right stabilizer was unremarkable. Both sustained slight thermal damage to the paint finish. Flight control cable continuity could not be established due to fragmentation and extensive thermal damage to the cockpit area. The engine and all observed components exhibited fire damage, corrosion, and some impact damage. All three propeller blades were attached to the propeller hub, which remained attached to the engine. Each propeller blade exhibited leading edge gouging and S-type bending. Both turbocharger units were partially impact separated from the engine and exhibited impact and heat damage. Attempts to verify engine continuity, valve train continuity, and cylinder compression by rotating the engine were unsuccessful. Visual confirmation of engine continuity was made using a borescope. No anomalies were noted with the engine or examined components. The National Weather Service produced a spot forecast for the approximate area of the accident site on the day of the accident. The forecast indicated sunny skies with areas of smoke and haze from the SQF Complex Fire. Stable air conditions continued to keep smoke in the valleys. Kern RiverValley was impacted by unhealthy to hazardous air quality. ## Aircraft - Registration: [N818S](https://openairdocs.org/deregistered/N818S-2022-05-09), registration cancelled 2022-05-09, S/N D-9101, built 1970 (OpenAirDocs) - Reported make and model: Beech 35 (V35B) - Registry model: [Beech V35B](https://openairdocs.org/model/beech-v35b) (registry code 1151548) (OpenAirDocs) - Registry engine: [Continental IO-520 series](https://openairdocs.org/engine/continental-io-520-series) (registry code 17032, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: D-9101 - Year built: 1970 - Airframe hours: 2566 - Engines: Continental TSIO-520-D 285 horsepower reciprocating - Damage: Destroyed - Fire: On-Ground - Flight: Personal, Part 91 - Operator: Nepinsky Brian C - Registered owner: Nepinsky Brian C - Airworthiness certificate: Standard, Normal - Last inspection: Annual, June 22, 2020 - Departed: KVIS, Visalia, CA - Destination: KEED, Needles, CA ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot-rated passenger; age 45; injuries: fatal; private; airplane ratings: single-engine land; medical: unknown; toxicology performed; flight hours: 630 total - Pilot; age 82; airline transport, commercial; airplane ratings: single-engine sea, single-engine land, multi-engine land; instrument ratings: airplane; medical: unknown; flight hours: 38,000 total ## Weather - Conditions: Instrument (IMC), Day - Wind: 260° at 5 knots - Visibility: 8 statute miles - Temperature: 90 °F, dew point 55 °F - Altimeter: 29.96 inHg - Observed at: PTV, 31 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 20200904016619A](https://openairdocs.org/incident/20200904016619A), Sep 4, 2020: Beech V35B, Three Rivers, CA, Destroyed, 2 fatal. On September 4, 2020 at approximately 11:30 pacific standard time (local time), aircraft N818S, Beech V35B serial number D-9101, departed visalia airport… ## Docket (9 files) The files NTSB released with the investigation on July 7, 2022, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=101919. 15.0 MB in all. - Medical factual report (item 1, PDF, 6 pages, 252 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13307160&FileExtension=pdf&FileName=WPR20LA295_MedicalFactualReport-Rel.pdf - Meteorology factual report (item 2, PDF, 28 pages, 4.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11634458&FileExtension=pdf&FileName=WPR20LA295%20-%20Three%20Rivers,%20CA%20WX%20Factual-Rel.pdf - Examination - field notes (item 3, PDF, 7 pages, 8 photos, 938 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13984667&FileExtension=pdf&FileName=Field%20Notes%20WPR20LA295-Rel.pdf - National park service report extracts (item 4, PDF, 4 pages, 135 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13986314&FileExtension=pdf&FileName=Memorandum%20of%20Record%20-%20NPS%20Report%20Extracts-Rel.pdf - Afrcc flight path (item 5, PDF, 1 page, 1.4 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=14100441&FileExtension=pdf&FileName=AFRCC%20Data-Rel.pdf - Statement of party representatives to NTSB investigation (item 6, PDF, 1 page, 752 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=14131603&FileExtension=pdf&FileName=WPR20LA295%20Party%20Form_Redacted-Rel.pdf - Release of aircraft wreckage, NTSB form 6120.15 (item 7, PDF, 2 pages, 176 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13821143&FileExtension=pdf&FileName=Wreckage%20Release-%20signed1_Redacted-Rel.pdf - Toxicological report (item 8, PDF, 2 pages, 639 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13308228&FileExtension=pdf&FileName=toxicology_Redacted-Rel.pdf - Photos (item 9, PDF, 6 pages, 6 photos, 6.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13987865&FileExtension=pdf&FileName=Photos%20WPR20LA295-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.