# NTSB WPR23LA031: Cessna 150G, N3131J, Star Valley, AZ, November 11, 2022 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Class 3 · Limited · Final report - Date: November 11, 2022, 12:07 local (19:07 UTC) - Place: Star Valley, AZ · Payson / Knoll Lake - Coordinates: 34.445683, -111.06629 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=34.4457&lon=-111.0663&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute-cruise: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) - Highest injury: Serious injuries - Injuries: 1 serious - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Western Pacific Region - Parties: FAA - NTSB case key (mKey): 106290 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR23LA031 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/106290/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=106290 - Page: https://openairdocs.org/ntsb/WPR23LA031 ## Probable cause The failure of the No. 1 cylinder exhaust or intake valve which resulted in the partial loss of engine power and subsequent impact with terrain. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Engine (reciprocating): recip eng cyl section](https://openairdocs.org/ntsb-findings/01058530): Aircraft › Aircraft power plant · Failure (probable cause); cases with it: [Cessna 150G, 1 case](https://openairdocs.org/ntsb-findings/01058530/cases.md?model=2071816), [All aircraft, 373 cases](https://openairdocs.org/ntsb-findings/01058530/cases.md) - [Performance/control parameters: altitude](https://openairdocs.org/ntsb-findings/01062012): Aircraft › Aircraft oper/perf/capability · Attain/maintain not possible; cases with it: [Cessna 150G, 2 cases](https://openairdocs.org/ntsb-findings/01062012/cases.md?model=2071816), [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: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) (defining event); cases with it: [Cessna 150G, 6 cases](https://openairdocs.org/ntsb-events/342/sequence.md?model=2071816), [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/sequence.md) - [Enroute-cruise: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Cessna 150G, 13 cases](https://openairdocs.org/ntsb-events/440/sequence.md?model=2071816), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) ## Analysis The pilot was enroute during a cross-country flight when the engine began running rough. He attempted to land in a clearing, but the airplane collided with trees and came to rest inverted before reaching the desired landing area. Postaccident examination of the engine revealed that the No. 1 cylinder exhaust valve had separated and was imbedded in the face of the No. 1 piston, cracking the piston. A portion of the intake valve was missing, and a portion of a valve was recovered inside the heat exchanger. Either a failed intake or exhaust valve would have resulted in a partial loss of engine power, but damage to the No. 1 piston and its intake and exhaust valves prevented determination of the initiating failure within the cylinder. ## Factual narrative On November 11, 2022, about 1207 mountain standard time, a Cessna C-150 airplane, N3131J, was substantially damaged when it was involved in an accident near Star Valley, Arizona. The pilot was seriously injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The airplane was the second airplane in a flight of two that departed Phoenix Deer Valley Airport (DVT) Phoenix, Arizona, at 1115 with a planned destination of Gallup Municipal Airport (GUP), Gallup, New Mexico. The pilot stated he was climbing over rising terrain and about 1,000 ft above the ground when the engine started running rough. He applied carburetor heat and manipulated the engine controls, but the engine did not respond, and the engine rpm continued to decrease. He attempted to land in a clearing but collided with trees before reaching the desired landing area. The airplane came to rest inverted. The engine was examined and damage consistent with metal-to-metal contact was observed to both the top and bottom spark plugs of the No. 1 cylinder following their removal. The No. 1 cylinder was removed, and the exhaust valve and a portion of the intake valve were found to have separated from their valve stem and valve face, respectfully. The exhaust valve was imbedded in the piston face and the piston was cracked. A portion of an intake valve was recovered inside the heat exchanger. Damage to the exhaust valve and piston precluded additional examination to determine the failure mode of either valve. At the time of the accident, the engine had accumulated about 993 hours since overhaul and about 32 hours since the last annual inspection that was completed on May 13, 2022. ## Aircraft - Registration: [N3131J](https://openairdocs.org/deregistered/N3131J-2024-05-01), registration cancelled 2024-05-01, S/N 15065831, built 1966 (OpenAirDocs) - Reported make and model: CESSNA 150G - Registry model: [Cessna 150G](https://openairdocs.org/model/cessna-150g) (registry code 2071816) (OpenAirDocs) - Registry engine: [Continental 0-200 series](https://openairdocs.org/engine/continental-0-200-series) (registry code 17020, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 15065831 - Year built: 1966 - Airframe hours: 6035.5 - Engines: Continental O-200A 100 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Flying Wild Arizona LLC - Registered owner: Flying Wild Arizona LLC - Airworthiness certificate: Standard, Normal - Last inspection: Annual, May 13, 2022 - Departed: KDVT, Deer Valley, AZ - Destination: KGUP, Gallup, NM - Equipment: Electronic flight bag or handheld device, ADS-B ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 51; injuries: serious; private, airline transport, commercial; airplane ratings: single-engine sea, multi-engine land, single-engine land; instrument ratings: airplane; medical: class 2; last flight review January 29, 2022; seat: left; restraint: 3-point; flight hours: 4,340 total, 1,021 in this make and model, 4,115 as pilot in command, 79 in the last 90 days, 21 in the last 30 days, 5 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: variable at 5 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 46 °F, dew point 27 °F - Altimeter: 30.21 inHg - Observed at: KPAN, 18 nm away - METAR: METAR KPAN 111855Z AUTO 19005KT 9SM CLR 08/M03 A3021 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 20221111020529A](https://openairdocs.org/incident/20221111020529A), Nov 11, 2022: Cessna 150G, Star Valley, AZ, Substantial damage. Aircraft lost engine RPM and was descending pilot attempted to land the aircraft in a field, impacted trees and suffered serious injuries. During inspection of… ## Docket (6 files) The files NTSB released with the investigation on May 16, 2024, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=106290. 462 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 11 pages, 1.9 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=16563919&FileExtension=pdf&FileName=6120_Redacted-Rel.pdf - Pilot's statement (item 2, PDF, 2 pages, 241 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=16563744&FileExtension=pdf&FileName=Timmons%20Statement%20N3131J-Rel.pdf - Engine examination notes (item 3, PDF, 6 pages, 6 photos, 960 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=16589008&FileExtension=pdf&FileName=MOR_Wreckage%20Examination%20WPR23LA031-Rel.pdf - Photos (item 4, PDF, 7 pages, 7 photos, 3.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=16588933&FileExtension=pdf&FileName=Photos%20WPR23LA031-Rel.pdf - Maintenance records (item 5, PDF, 12 pages, 456 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=16601534&FileExtension=pdf&FileName=Logbook%20Binder_Redacted-Rel.pdf - Release of aircraft wreckage, NTSB form 6120.15 (item 6, PDF, 2 pages, 180 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=16624728&FileExtension=pdf&FileName=Wreckage%20Release-%20Signed1_Redacted-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.