# NTSB CEN10LA450: Cessna T188C, N2085J, Montezuma, IN, July 29, 2010 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: July 29, 2010, 13:20 local (17:20 UTC) - Place: Montezuma, IN - Coordinates: 39.760555, -87.359725 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=39.7606&lon=-87.3597&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report May 21, 2012 - Report: Approved by Office Director - NTSB office: Central Region - Parties: Federal Aviation Administration, Indianapolis FSDO - NTSB case key (mKey): 76812 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN10LA450 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/76812/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=76812 - Page: https://openairdocs.org/ntsb/CEN10LA450 ## Probable cause The total loss of engine power due to an insufficient fastener preload that led to the failure of the No. 2 connecting rod assembly. ## 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 T188C, 1 case](https://openairdocs.org/ntsb-findings/01058530/cases.md?model=2073012), [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: Powerplant sys/comp malf/fail](https://openairdocs.org/ntsb-events/340); cases with it: [Cessna T188C, 1 case](https://openairdocs.org/ntsb-events/340/sequence.md?model=2073012), [All aircraft, 820 cases](https://openairdocs.org/ntsb-events/340/sequence.md) - [Enroute: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) (defining event); cases with it: [Cessna T188C, 1 case](https://openairdocs.org/ntsb-events/341/sequence.md?model=2073012), [All aircraft, 3,820 cases](https://openairdocs.org/ntsb-events/341/sequence.md) - [Landing: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Cessna T188C, 2 cases](https://openairdocs.org/ntsb-events/440/sequence.md?model=2073012), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) - [Landing: Landing gear collapse](https://openairdocs.org/ntsb-events/094); cases with it: [Cessna T188C, 1 case](https://openairdocs.org/ntsb-events/094/sequence.md?model=2073012), [All aircraft, 1,787 cases](https://openairdocs.org/ntsb-events/094/sequence.md) ## Analysis The pilot reported that, while en route to spray a field, the engine lost power and the windshield became obscured with oil. The pilot immediately turned into the wind and made a forced landing into a nearby cornfield. A postaccident examination revealed that the No. 2 connecting rod had separated from the engine crankshaft. Metallurgical examinations found polishing and wear patterns indicative of relative motion between the connecting rod components and an associated rod bolt head/nut. The nut threads were sheared as result of overload failure, consistent with impulse loading. The observed anomalies were consistent with an insufficient fastener preload on installation of the connecting rod bolt. The engine had accumulated 1,193 hours since its last major overhaul. It is likely that the rod bolt head/nut became loose during operation, which led to a failure of the assembly due to impulse loading. ## Factual narrative On July 29, 2010, at 1320 eastern daylight time, a Cessna model T188C airplane, N2085J, was substantially damaged during a forced landing following a total loss of engine power near Montezuma, Indiana. The pilot was not injured. The airplane was registered to and operated by Swing Wings, Inc., under the provisions of 14 Code of Federal Regulations Part 137 without a flight plan. Day visual meteorological conditions prevailed for the aerial-application flight that originated from Clinton Airport, Clinton, Indiana, at 1315. The pilot reported that while en route to the field to be sprayed there was total loss of engine power and the windshield became obscured with oil. The pilot immediately turned into the wind and made a forced landing into a nearby corn field. The airframe was substantially damaged after touchdown when the left main landing gear collapsed and the left wing impacted terrain. A postaccident examination conducted by a Federal Aviation Administration inspector established that the No. 2 connecting rod had separated from the engine crankshaft. A portion of the No. 2 connecting rod was found protruding through a hole in the engine crankcase. The engine was partially disassembled and the connecting rod components were sent to the National Transportation Safety Board's (NTSB) Materials Laboratory Division for metallurgical examination. The NTSB lab examination established that there were polishing and wear patterns on the washer faces of one rod bolt and a corresponding nut. Further examinations found similar wear and polishing on the No. 2 connecting rod and a rod cap. The observed polishing and wear patterns were indicative of relative motion between the connecting rod components and associated rod bolt head/nut. The nut threads were sheared, consistent with impulse loading. A review of available maintenance information revealed that the engine, a Continental model TSIO-520-T, had accumulated 1,193 hours since its last major overhaul. At 1325, the automated surface observing system at the Edgar County Airport, located about 16 miles west of the accident site, reported the following weather conditions: variable wind direction at 6 knots; visibility 10 miles; scattered clouds between 3,000 and 4,400 feet above ground level (agl); temperature 28 degrees Celsius; dew point 21 degrees Celsius; altimeter setting 30.10 inches of mercury. ## Aircraft - Registration: [N2085J](https://openairdocs.org/deregistered/N2085J-2020-11-14), registration cancelled 2020-11-14, S/N T18803375T, built 1978 (OpenAirDocs) - Reported make and model: CESSNA T188C - Registry model: [Cessna T188C](https://openairdocs.org/model/cessna-t188c) (registry code 2073012) (OpenAirDocs) - Registry engine: [Continental TSIO-520 series](https://openairdocs.org/engine/continental-tsio-520-series) (registry code 17040, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: T18803375T - Airframe hours: 5862 - Engines: Continental TSIO-520-T 310 horsepower reciprocating - Damage: Substantial damage - Flight: Aerial application, Part 137 - Operator: Swing Wings, Inc. - Registered owner: Swing Wings, Inc. - Airworthiness certificate: Standard, Utility; Special, Restricted (Special) - Last inspection: Annual, May 25, 2010 - Departed: 1I7, Clinton, IN - Destination: 1I7, Clinton, IN ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 65; injuries: none; commercial, flight instructor; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane, helicopter; medical: class 2, with waivers/limitations; last flight review June 30, 2010; seat: single; flight hours: 10,530 total, 229 in this make and model, 10,000 as pilot in command, 200 in the last 90 days, 185 in the last 30 days, 0 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: variable at 6 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 82 °F, dew point 70 °F - Altimeter: 30.10 inHg - Observed at: KPRG, 16 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 20100729040299A](https://openairdocs.org/incident/20100729040299A), Jul 29, 2010: Cessna T188C, Montezuma, IN, Substantial damage. Shortly after departure from clinton Indiana (1I7) airport at approximately 200 feet the engine quit and lubricating oil was thrown on the windscreen. The load… ## Other investigations on N2085J (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 CEN20CA229](https://openairdocs.org/ntsb/CEN20CA229), Jun 12, 2020: Cessna T188 (N2085J), McCurtain, OK, substantial damage. Probable cause: The pilot's failure to maintain the proper airspeed during a low altitude aerial application maneuver and his exceedance of the airplane’s critical angle of attack, which resulted in an aerodymanic… ## Docket (6 files) The files NTSB released with the investigation on April 23, 2012, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=76812. 2.2 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 500 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40366152&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Memorandum of Conversation with FAA Inspector Prendergast (item 2, .PDF, 56 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40366153&FileExtension=.PDF&FileName=Memorandum%20of%20Conversation%20with%20FAA%20Inspector%20Prendergast-Master.PDF - Materials Laboratory 15 - Factual Report 12-032 (4 images) (item 3, .PDF, 1.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40364808&FileExtension=.PDF&FileName=Materials%20Laboratory%2015%20-%20Factual%20Report%2012-032%20(4%20images)-Master.PDF - Photo 01 - Engine Overview, Photo provided by FAA (item 4, .PDF, 68 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40366154&FileExtension=.PDF&FileName=Photo%2001%20-%20Engine%20Overview,%20Photo%20provided%20by%20FAA-Master.PDF - Weather Reports, Excerpts (item 5, .PDF, 14 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40366157&FileExtension=.PDF&FileName=Weather%20Reports,%20Excerpts-Master.PDF - Evidence Control Documentation (item 6, .PDF, 336 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40366156&FileExtension=.PDF&FileName=Evidence%20Control%20Documentation-Redacted.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.