# NTSB CEN16LA306: Cessna 150L, N10770, Russellville, OH, August 5, 2016 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: August 4, 2016, 20:04 local (Aug 5, 2016, 00:04 UTC) - Place: Russellville, OH - Coordinates: 38.881942, -83.882774 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=38.8819&lon=-83.8828&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute-descent: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) - Highest injury: Minor injuries - Injuries: 1 minor, 1 uninjured - Status: Completed, report June 20, 2017 - Report: Approved by Office Director - NTSB office: Central Region - Parties: FAA Flight Standards District Office - NTSB case key (mKey): 93773 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN16LA306 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/93773/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=93773 - Page: https://openairdocs.org/ntsb/CEN16LA306 ## Probable cause A partial loss of engine power due to a fatigue crack of the No. 2 cylinder cooling fin, which resulted in failure of the No. 2 cylinder. ## 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 150L, 6 cases](https://openairdocs.org/ntsb-findings/01058530/cases.md?model=2071826), [All aircraft, 373 cases](https://openairdocs.org/ntsb-findings/01058530/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute-descent: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) (defining event); cases with it: [Cessna 150L, 19 cases](https://openairdocs.org/ntsb-events/341/sequence.md?model=2071826), [All aircraft, 3,820 cases](https://openairdocs.org/ntsb-events/341/sequence.md) - [Emergency descent: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Cessna 150L, 18 cases](https://openairdocs.org/ntsb-events/440/sequence.md?model=2071826), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) - [Landing-landing roll: Nose over/nose down](https://openairdocs.org/ntsb-events/096); cases with it: [Cessna 150L, 11 cases](https://openairdocs.org/ntsb-events/096/sequence.md?model=2071826), [All aircraft, 2,287 cases](https://openairdocs.org/ntsb-events/096/sequence.md) ## Analysis As the private pilot was descending the airplane for landing, he heard a loud "bang," and the engine subsequently began running rough. Unable to maintain altitude, the pilot conducted a forced landing to a soybean field, during which the airplane impacted a ditch and nosed over. Examination of the engine revealed that the No. 2 cylinder was completely separated between the flange and the head. Examination of the cylinder revealed a fatigue crack that initiated at a cooling fin valley on the exterior surface. The fatigue crack grew around 40% of the circumference of the cylinder, and overstress led to the eventual cylinder fracture. A metallographic cross-section of the cylinder revealed corrosion pits under the paint and primer. The alloy is not necessarily susceptible to pitting, but crevice corrosion near an unpainted area or exposure to salt environments can lead to similar corrosion features. ## Factual narrative On August 4, 2016, at 2004 eastern daylight time, the pilot of a Cessna 150L, N10770, impacted terrain in a soybean field near Russellville, Ohio, after a loss of engine power. The private pilot on board sustained a minor injury and the pilot-rated passenger was not injured. The airplane was substantially damaged. The airplane was registered to and operated by a private individual under the provisions of 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed at the time of the accident, and no flight plan had been filed. The local flight originated from Brown County Airport (KGEO), Georgetown, Ohio, about 1945.The pilots told an FAA inspector that while they were descending for landing, they heard a loud "bang" and the engine began running rough. Unable to maintain altitude, they made a forced landing in a soybean field. The airplane struck a ditch and nosed over. Examination of the engine revealed the number 2 cylinder had completely separated between the flange and the head. The pilot was instructed to ship the cylinder halves to the National Transportation Safety Board's (NTSB) Materials Laboratory for examination. According to the Materials Laboratory's Factual Report (16-110), the cylinder had fractured about the circumference of the seventh cooling fin valley through approximately 40% of the cross section. The fracture was relatively flat, exhibited a reflective luster, and was oriented in the direction of piston movement. The fracture surface revealed the presence of crack arrest marks, which were consistent with progressive cracking due to fatigue. Additionally, several cooling fin flange surfaces exhibited small circular features consistent with pitting. An initial thumbnail crack was present adjacent to the crack initiation site, with radial marks and crack arrest marks propagating outward. Fatigue striations were present, consistent with fatigue crack propagation. The crack initiation site on the head side of the fracture surface consisted of three stepped features containing ratchet marks between the steps, consistent with multiple crack initiation sites that had coalesced as the fatigue cracks grew and propagated inward. The mating (open piston side) fracture surface exhibited three ridge shapes, consistent with the previously observed ratchet marks on the head side fracture surface. According to the engine maintenance records, cylinder number 2 (serial number 0049), manufactured by Superior Air Parts, Coppell, Texas, was overhauled on April 14, 2000. The overhaul included grounding the intake and exhaust valve seats, grounding the intake valve, replacing the intake and exhaust guides, and replacing the exhaust valve. The cylinder was then pressure checked and returned to service. ## Aircraft - Registration: [N10770](https://openairdocs.org/deregistered/N10770-2020-05-29), registration cancelled 2020-05-29, S/N 15075023, built 1973 (OpenAirDocs) - Reported make and model: CESSNA 150L - Registry model: [Cessna 150L](https://openairdocs.org/model/cessna-150l) (registry code 2071826) (OpenAirDocs) - Registry engine: [Continental 0-200 series](https://openairdocs.org/engine/continental-0-200-series) (registry code 17020, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 15075023 - Year built: 1973 - Airframe hours: 6358 - Engines: Continental O-200-A 100 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, April 16, 2016, 11 hours before - Departed: GEO, Russellville, OH - Destination: GEO, Russellville, OH - Airport: KGEO, Brown County - Equipment: Stall warning system ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 46; injuries: minor; private; airplane ratings: single-engine land; medical: class 3, without waivers/limitations; last flight review September 8, 2015; seat: left; restraint: lap only; flight hours: 195 total, 195 in this make and model, 140 as pilot in command, 20 in the last 90 days, 10 in the last 30 days, 1 in the last 24 hours - Pilot-rated passenger; age 44; injuries: none; airline transport; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, with waivers/limitations; seat: right; restraint: lap only; flight hours: 8,000 total, 1 in this make and model ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: none ## 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 20160804013159A](https://openairdocs.org/incident/20160804013159A), Aug 4, 2016: Cessna 150L, Russellville, OH, Substantial damage. August 4th, 2016, 19:45PM eastern time, the pilot, along with one passenger, took off from kgeo on runway 18 heading south bound on a local flight.… ## Other investigations on N10770 (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 IAD7KDLQ26](https://openairdocs.org/ntsb/IAD7KDLQ26), May 18, 1975: Cessna 150 (N10770), Versailles, KY, substantial damage ## Docket (4 files) The files NTSB released with the investigation on May 2, 2017, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=93773. 8.5 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 257 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40453767&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Materials Laboratory Factual Report (item 2, .PDF, 15 photos, 5.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40451622&FileExtension=.PDF&FileName=Materials%20Laboratory%20Factual%20Report-Master.PDF - Pertinent Excerpts, Engine Maintenance Records (item 3, .PDF, 141 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40451623&FileExtension=.PDF&FileName=Pertinent%20Excerpts,%20Engine%20Maintenance%20Records-Master.PDF - Report Photos (item 4, .PDF, 3 photos, 2.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40451624&FileExtension=.PDF&FileName=Report%20Photos-Master.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.