# NTSB WPR23LA077: Beech V35B, N65Y, Livermore, CA, December 25, 2022 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Class 3 · Limited · Final report - Date: December 24, 2022, 16:53 local (Dec 25, 2022, 00:53 UTC) - Place: Livermore, CA - Coordinates: 37.695076, -121.80188 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=37.6951&lon=-121.8019&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Defining event: [Initial climb: Fuel starvation](https://openairdocs.org/ntsb-events/191) - Highest injury: Serious injuries - Injuries: 1 serious - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 106499 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR23LA077 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/106499/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=106499 - Page: https://openairdocs.org/ntsb/WPR23LA077 ## Probable cause The pilot’s inadvertent use of the mixture control instead of the throttle, which resulted in fuel starvation and the subsequent loss of engine power. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Use of equip/info: use of equip/system](https://openairdocs.org/ntsb-findings/02063015): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Beech V35B, 7 cases](https://openairdocs.org/ntsb-findings/02063015/cases.md?model=1151548), [All aircraft, 1,391 cases](https://openairdocs.org/ntsb-findings/02063015/cases.md) - [Engine controls: mixture control](https://openairdocs.org/ntsb-findings/01057602): Aircraft › Aircraft power plant · Unintentional use/operation (probable cause); cases with it: [Beech V35B, 2 cases](https://openairdocs.org/ntsb-findings/01057602/cases.md?model=1151548), [All aircraft, 41 cases](https://openairdocs.org/ntsb-findings/01057602/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Initial climb: Fuel starvation](https://openairdocs.org/ntsb-events/191) (defining event); cases with it: [Beech V35B, 3 cases](https://openairdocs.org/ntsb-events/191/sequence.md?model=1151548), [All aircraft, 733 cases](https://openairdocs.org/ntsb-events/191/sequence.md) - [Takeoff: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Beech V35B, 20 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=1151548), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The pilot planned on remaining in the traffic pattern for night flight. Shortly after takeoff, while on the upwind leg of the traffic pattern, the cabin door opened; the pilot stated that he slowed the airplane by using the throttle. He added that it was dark and that he could not see the instruments, but he could see the engine control knobs. The pilot realized the airplane was descending toward a building when he heard the tower controller say “climb, climb, climb.” The pilot then “pushed the throttle in.” The airplane continued to descend and impacted a building. Additionally, the pilot added that due to the dark conditions, he may have mistakenly pulled the mixture control knob to slow the airplane down instead of using the throttle. Postaccident examination of the airframe and engine revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation. Continuity of the throttle, propeller, and mixture controls was established from the cockpit to their respective control arms. Examination of the throttle revealed the throttle knob was about 1 inch from full forward, the mixture control was about 2 inches from full forward, and the propeller controller lever was about ½ inch from full forward. The pilot likely inadvertently manipulated the mixture to a lean position instead of the pulling back on the throttle, which resulted in the reduction of engine power. ## Factual narrative On December 24, 2022, about 1653 Pacific standard time, a Beech V35B, N65Y, was substantially damaged when it was involved in an accident near Livermore Municipal Airport (LVK), Livermore, California. The pilot was seriously injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot reported that he departed runway 7L at LVK with the intention of remaining within the airport traffic pattern. While on the upwind leg of the traffic pattern, the cabin door opened, and he slowed the airplane down “using the throttle.” He stated that due to the wind noise, he could not hear the tower controller well and that he could not see the instruments but could see the engine control knobs. The pilot then heard the tower controller say “climb, climb, climb,” and at that time, the pilot realized the airplane was descending toward a building. The pilot stated that he “pushed the throttle in” but the airplane continued to descend and impacted a building. The pilot added that he usually takes off with the mixture full rich, the propeller full forward, and the throttle at full. When he slowed the airplane, he “slowed it with the throttle.” Due to the dark conditions, he could not be sure if he mistakenly pulled the mixture control knob to slow the airplane down. A witness, located near the accident site, reported that they heard the accident airplane’s engine sputtering as it passed by his location, followed by the sound of the airplane impacting a building. Examination of the recovered wreckage revealed no preaccident mechanical malfunctions or failures with the airplane that would have precluded normal operation. Fuel expelled from various fuel lines when they were removed. The engine-driven fuel pump was removed, and the drive shaft was found intact. The fuel pump drive shaft rotated freely by hand. The fuel pump was disassembled and found to be unremarkable. Continuity of the throttle, propeller, and mixture controls was established from the cockpit to their respective control arms and moved from stop to stop by hand. Examination of the engine controls in the cockpit revealed the throttle knob was about 1 inch from full forward, the mixture was about 2 inches from full forward, and the propeller lever was about 1/2 inch from full forward. ## Aircraft - Registration: [N65Y](https://openairdocs.org/aircraft/N65Y), registered now, S/N D-10080, built 1977 (OpenAirDocs) - Reported make and model: BEECH 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-10080 - Year built: 1977 - Engines: Continental Motors IO-520-BA reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Airport: LVK, Livermore Municipal Airport, runway 7L, 5,253 × 100 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 79; injuries: serious; commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: basicmed; seat: left ## Weather - Conditions: Visual (VMC), Dusk - Wind: 80° at 8 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 54 °F, dew point 45 °F - Altimeter: 30.34 inHg - Observed at: KLVK, 1 nm away - METAR: METAR KLVK 250053Z 08008KT 10SM HZ CLR 12/07 A3034 RMK AO2 SLP273 T01220072= ## 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 20221224022489A](https://openairdocs.org/incident/20221224022489A), Dec 24, 2022: Beech V35B, Livermore, CA, Destroyed. [privacy data omitted] Departed Livermore municipal airport on runway 7 for the pattern. Shortly after takeoff the pilot reported that his door had popped open… ## Docket (5 files) The files NTSB released with the investigation on January 14, 2025, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=106499. 2.7 MB in all. - Record of conversation - pilot (item 1, PDF, 2 pages, 171 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=18065054&FileExtension=pdf&FileName=ROC%20Pilot%201-Rel.pdf - FAA record of conversation with the pilot (item 2, PDF, 2 pages, 901 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=18064373&FileExtension=pdf&FileName=FAA%20ROC%20Pilot-Rel.pdf - FAA record of conversation with a witness (item 3, PDF, 2 pages, 899 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=18064917&FileExtension=pdf&FileName=FAA%20Witness%20ROC-Rel.pdf - NTSB airframe and engine examination summary (item 4, PDF, 3 pages, 100 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=18065331&FileExtension=pdf&FileName=airframe%20and%20engine%20examination-Rel.pdf - Photo array (item 5, PDF, 4 pages, 3 photos, 672 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=18065126&FileExtension=pdf&FileName=photo%20array-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.