# NTSB WPR20LA097: Cessna 170, N5478C, Baker City, OR, February 27, 2020 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 3 · Limited · Final report - Date: February 27, 2020, 15:00 local (23:00 UTC) - Place: Baker City, OR - Coordinates: 44.730556, -117.83889 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=44.7306&lon=-117.8389&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) - 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-FSDO - NTSB case key (mKey): 101013 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR20LA097 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/101013/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=101013 - Page: https://openairdocs.org/ntsb/WPR20LA097 ## Probable cause The failure of the No. 2 connecting rod bearing as a result of oil starvation due to a contaminated oil filter screen. ## 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 170A, 2 cases](https://openairdocs.org/ntsb-findings/01058530/cases.md?model=2072304), [All aircraft, 373 cases](https://openairdocs.org/ntsb-findings/01058530/cases.md) - [Terrain: rough terrain](https://openairdocs.org/ntsb-findings/03021015): Environmental issues › Physical environment · Effect on equipment (probable cause); cases with it: [Cessna 170A, 1 case](https://openairdocs.org/ntsb-findings/03021015/cases.md?model=2072304), [All aircraft, 442 cases](https://openairdocs.org/ntsb-findings/03021015/cases.md) - [Fluids: oil](https://openairdocs.org/ntsb-findings/01071020): Aircraft › Fluids/misc hardware · Fluid level (probable cause); cases with it: [Cessna 170A, 1 case](https://openairdocs.org/ntsb-findings/01071020/cases.md?model=2072304), [All aircraft, 174 cases](https://openairdocs.org/ntsb-findings/01071020/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) (defining event); cases with it: [Cessna 170A, 1 case](https://openairdocs.org/ntsb-events/342/sequence.md?model=2072304), [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/sequence.md) - [Landing-landing roll: Collision during takeoff/land](https://openairdocs.org/ntsb-events/490); cases with it: [Cessna 170A, 5 cases](https://openairdocs.org/ntsb-events/490/sequence.md?model=2072304), [All aircraft, 1,309 cases](https://openairdocs.org/ntsb-events/490/sequence.md) ## Analysis The pilot reported that during a local flight, the engine started to knock and vibrate, and the oil pressure indication was low. He initiated a precautionary landing to an open field, and during the landing rollout, the airplane impacted a small ditch, which resulted in substantial damage to the left wing. A postaccident examination of the engine revealed that the No. 2 connecting rod was separated from the crankshaft. The No. 2 connecting rod journal exhibited thermal distress and mechanical damage. The remaining connecting rod journals and the crankshaft main bearings also exhibited thermal discoloration consistent with oil starvation. When the engine was rotated, no oil flow was observed through the crank journals and lifters. The oil filter screen was covered in dark thick oil and metallic debris and was collapsed. It is likely that the contaminated oil filter screen collapsed under pressure from the oil pump, which prevented the normal flow of oil through the engine; this resulted in the oil starvation of the No. 2 connecting rod bearing and subsequent separation of the connecting rod from the crankshaft. ## Factual narrative On February 27, 2020, about 1500 mountain standard time, a Cessna 170, N5478C, was substantially damaged when it was involved in an accident near Baker City, Oregon. The pilot and one 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 purpose of the flight was to warm up the oil before a scheduled annual inspection and oil change. About 15 minutes into the local flight, the engine started to “knock and vibrate badly,” and the oil pressure indication was low. The pilot initiated a precautionary landing to an open field, and during the landing rollout, the airplane impacted a small ditch. The left wing sustained substantial damage. A postaccident examination of the engine revealed that the No. 2 connecting rod was separated from the crankshaft. The No. 2 connecting rod journal exhibited thermal distress and mechanical damage. The remaining connecting rod journals also exhibited thermal discoloration. The crankshaft main bearings exhibited thermal discoloration and excessive wear. When the engine was rotated, no oil flow was observed through the crank journals and lifters. The oil sump contained metal fragments, and the oil filter screen was covered in dark thick oil and metallic debris and was collapsed. The engine contained about 6 quarts of oil before the examination. According to the pilot, who was the airplane owner, the engine had 465 hours of operation since the last overhaul. ## Aircraft - Registration: [N5478C](https://openairdocs.org/deregistered/N5478C-2022-07-30), registration cancelled 2022-07-30, S/N 19512, built 1950 (OpenAirDocs) - Reported make and model: Cessna 170 (A) - Registry model: [Cessna 170A](https://openairdocs.org/model/cessna-170a) (registry code 2072304) (OpenAirDocs) - Registry engine: [Continental C145 series](https://openairdocs.org/engine/continental-c145-series) (registry code 17012, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 19512 - Year built: 1950 - Engines: Continental O-300 145 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, September 1, 2018 - Departed: BKE, Baker City, OR - Destination: BKE, Baker City, OR - Airport: BKE, Baker City Muni ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 71; injuries: none; private; airplane ratings: single-engine land; medical: class 3, with waivers/limitations; seat: left; restraint: lap only; flight hours: 2,500 total, 1,000 in this make and model, 3 in the last 90 days, 1 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 30° at 6 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 57 °F, dew point 30 °F - Altimeter: 30.37 inHg - Observed at: KBKE, 7 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 20200227002099A](https://openairdocs.org/incident/20200227002099A), Feb 27, 2020: Cessna 170A, Baker City, OR, Substantial damage. On the afternoon of February 27, 2020, the pilot of Cessna 170A N5487C departed the airport at Baker City, OR (bkr) with one passenger planning a short local… ## Other investigations on N5478C (1) 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. - [NTSB LAX83LA392](https://openairdocs.org/ntsb/LAX83LA392), Aug 15, 1983: Cessna 17OA (N5478C), Ramona, CA, substantial damage ## Docket (8 files) The files NTSB released with the investigation on June 8, 2022, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=101013. 12.2 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 11 pages, 5.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13260144&FileExtension=pdf&FileName=6120_Redacted-Rel.pdf - Mechanic's engine examination notes 05-20-2021 (item 2, PDF, 1 page, 308 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13260416&FileExtension=pdf&FileName=Examination%20Notes-Rel.pdf - Email-mechanic's examination notes 07-03-2020 (item 3, PDF, 3 pages, 7 photos, 541 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13259396&FileExtension=pdf&FileName=Email-07-03-2020%20Re_%20WPR20LA097%20Baker%20City,%20OR-Engine%20Examination_Redacted-Rel.pdf - Continental O-300 lubrication figures (item 4, PDF, 3 pages, 571 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13599090&FileExtension=pdf&FileName=Continental%20Motors-Lubrication%20Charts-Rel.pdf - Continental O-300 overhaul manual-lubrication system (item 5, PDF, 1 page, 98 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13598989&FileExtension=pdf&FileName=Lubrication%20Discription%20from%20O-300%20overhaul-Rel.pdf - Accident site photo (courtesy of first responders) (item 6, PDF, 1 page, 653 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13598601&FileExtension=pdf&FileName=Accident%20site%20photo-Rel.pdf - Photo array-engine exam (courtesy of mechanic) (item 7, PDF, 14 pages, 3.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13967146&FileExtension=pdf&FileName=Photo%20Array%20of%20Exam-Hired%20Mechanic-Rel.pdf - Ntsb-photo examination report (item 8, PDF, 10 pages, 14 photos, 1.4 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13599408&FileExtension=pdf&FileName=WPR20LA097%20Photo%20Examination%20Report-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.