# NTSB ERA11LA383: Cessna 150L, N150ET, Plymouth, MA, July 4, 2011 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: July 4, 2011, 13:00 local (17:00 UTC) - Place: Plymouth, MA - Coordinates: 41.908332, -70.733329 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=41.9083&lon=-70.7333&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Defining event: [Initial climb: Powerplant sys/comp malf/fail](https://openairdocs.org/ntsb-events/340) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report January 17, 2012 - Report: Approved by Office Director - NTSB office: Eastern Region Aviation - Parties: FAA/FSDO - NTSB case key (mKey): 81011 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA11LA383 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/81011/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=81011 - Page: https://openairdocs.org/ntsb/ERA11LA383 ## Probable cause A partial loss of engine power during initial climb due to a stuck cylinder valve, which resulted from excessive corrosion and carbon deposits on the valve springs due to inadequate maintenance. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Maintenance](https://openairdocs.org/ntsb-findings/02062000): Personnel issues › Task performance · Not specified (probable cause); cases with it: [Cessna 150L, 1 case](https://openairdocs.org/ntsb-findings/02062000/cases.md?model=2071826), [All aircraft, 143 cases](https://openairdocs.org/ntsb-findings/02062000/cases.md) - [Engine (reciprocating): recip eng cyl section](https://openairdocs.org/ntsb-findings/01058530): Aircraft › Aircraft power plant · Fatigue/wear/corrosion (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) - [Engine (reciprocating): recip eng cyl section](https://openairdocs.org/ntsb-findings/01058530): Aircraft › Aircraft power plant · Malfunction (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. - [Initial climb: Powerplant sys/comp malf/fail](https://openairdocs.org/ntsb-events/340) (defining event); cases with it: [Cessna 150L, 3 cases](https://openairdocs.org/ntsb-events/340/sequence.md?model=2071826), [All aircraft, 820 cases](https://openairdocs.org/ntsb-events/340/sequence.md) - [Initial climb: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342); cases with it: [Cessna 150L, 11 cases](https://openairdocs.org/ntsb-events/342/sequence.md?model=2071826), [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/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: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Cessna 150L, 37 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=2071826), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis During initial climb, the engine began to run rough and experienced a partial loss of power. The pilot elected to land straight ahead into a cranberry bog. The pilot believed the loss of engine power was due to a stuck cylinder valve. Postaccident examination of the engine revealed that the No. 2 cylinder intake and exhaust valve springs exhibited excessive corrosion and carbon deposits, consistent with lack of use, which made them more susceptible to sticking. The extent of the corrosion was such that it presented over a long period of time and should have been addressed during routine maintenance. No other defects were noted with the engine that would have resulted in a partial loss of power. The airplane had been operated for 17 hours since its most recent annual inspection, which was completed 11 months prior to the accident. The engine had been operated for 256 hours since its most recent overhaul, which was completed more than 10 years prior to the accident. The same airplane was involved in a forced landing to a cranberry bog 8 years earlier due to a stuck cylinder valve. ## Factual narrative On July 4, 2011, about 1300 eastern daylight time, a Cessna 150L, N150ET, operated by a private individual, was substantially damaged during a forced landing to a cranberry bog, following a partial loss of engine power during takeoff from Plymouth Municipal Airport (PYM), Plymouth, Massachusetts. The certificated commercial pilot was not injured. The personal flight was conducted under the provisions of 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed and no flight plan was filed for the planned local flight. The pilot reported that during initial climb, the engine began to run rough and experienced a partial loss of power. The pilot elected to land straight ahead into a cranberry bog. During the landing, the landing gear, propeller, and engine firewall sustained substantial damage. The pilot further stated that the loss of engine power was due to a stuck cylinder valve. Examination of the engine by a Federal Aviation Administration (FAA) inspector revealed that the No. 2 cylinder intake and exhaust valve springs exhibited corrosion and carbon deposits. The other cylinder valve springs also exhibited corrosion, consistent with lack of operation; however, they did not exhibit the carbon build-up similar to the No. 2 cylinder valve springs. The inspector also checked the fuel system, cylinder compression, sparkplugs, the carburetor, and the exhaust system, and no other defects were noted. According to maintenance records, the airplane had been operated for 17 hours since its most recent annual inspection, which was performed on August 14, 2010. The engine had been operated for 256 hours since its most recent overhaul, which was completed more than 10 years prior to the accident. Review of FAA records revealed that the same airplane was involved in a forced landing to a cranberry bog in 2003, due to a stuck cylinder valve. ## Aircraft - Registration: [N150ET](https://openairdocs.org/deregistered/N150ET-2012-07-13), registration cancelled 2012-07-13, S/N 15073072, built 1971 (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: 15073072 - Airframe hours: 4500 - Engines: CONT MOTOR O-200 100 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Richard C Murphy - Registered owner: Richard C Murphy - Airworthiness certificate: Standard, Normal - Last inspection: Annual, August 14, 2010, 17 hours before - Departed: PYM, Plymouth, MA - Destination: PYM, Plymouth, MA - Airport: PYM, Plymouth ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 70; injuries: none; commercial, flight instructor; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 3, with waivers/limitations; last flight review February 17, 2011; seat: left; flight hours: 4,327 total, 3,001 in this make and model, 4,023 as pilot in command, 44 in the last 90 days, 20 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 280° at 11 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 84 °F, dew point 64 °F - Altimeter: 29.79 inHg - Observed at: PYM ## 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 20110704011799A](https://openairdocs.org/incident/20110704011799A), Jul 4, 2011: Cessna 150L, Plymouth, MA, Substantial damage. Aircraft departed from Plymouth muni. Airport and attained 500 hunderd feet in altitude when the engine began running very rough and lost power. The pilot saw… ## Docket (4 files) The files NTSB released with the investigation on November 28, 2011, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=81011. 655 KB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 484 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40358131&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - FAA Inspector Statement (item 2, .PDF, 47 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40358132&FileExtension=.PDF&FileName=FAA%20Inspector%20Statement-Redacted.PDF - Photo: Wreckage (Courtesy of FAA) (item 3, .PDF, 64 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40358133&FileExtension=.PDF&FileName=Photo%3A%20%20Wreckage%20(Courtesy%20of%20FAA)-Master.PDF - Photo: Cylinder No. 2 (Courtesy of FAA) (item 4, .PDF, 60 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40358134&FileExtension=.PDF&FileName=Photo%3A%20%20Cylinder%20No.%202%20(Courtesy%20of%20FAA)-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.