# NTSB CHI07LA039: Cessna 140, N76379, Vienna, MO, December 9, 2006 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: December 9, 2006, 14:30 local (20:30 UTC) - Place: Vienna, MO - Coordinates: 38.925834, -91.916114 - Nearby events: https://openairdocs.org/map.md?lat=38.9258&lon=-91.9161&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report January 31, 2008 - Report: Approved by Office Director - Parties: Federal Aviation Administration - NTSB case key (mKey): 65060 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI07LA039 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/65060/pdf - Page: https://openairdocs.org/ntsb/CHI07LA039 ## Probable cause The loss of engine power during cruise flight due to fatigued crankshaft cluster gear bolts and the inadequate major overhaul of the engine that was last performed by other maintenance personnel. An additional cause was a subsequent major engine overhaul not performed by the pilot after he purchased the airplane and operated it with an engine that exceeded the engine manufacturer's time between overhaul criteria. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(total) - mech failure/malf, cruise - engine assembly,other - fatigue (cause) - maintenance,overhaul,major - not performed, pilot in command (cause) - maintenance,overhaul,major - inadequate, other maintenance personnel (cause) - Forced landing, descent - emergency - In flight collision with terrain/water, emergency descent/landing - terrain condition - ground ## Analysis The airplane impacted terrain during a forced landing after a loss of engine power. The pilot recently purchased the airplane and had taken delivery of it on the day of the accident. Examination of the engine revealed three of the crankshaft cluster gear bolts were fractured completely through. The bolt fracture surface features were consistent with fatigue. Additionally, the crankshaft gear had a hole where a crankshaft dowel had been installed following a design change in 1948 and was reflected in subsequent maintenance manuals. The dowel is used as a reference in machining the crankshaft. During the disassembly, the tappets fell out when the engine was overturned during the disassembly. It was later noted that the tappets did not contain retaining hardware. The interior of the crankcase halves contained a black colored residue when the oil was drained. Logbook entries show that the engine was last overhauled on July 25, 1990, and accumulated a total time since overhaul of 257.5 hours. Teledyne Continental Service Information Letter, SIL98-9A, Time Between Overhaul Periods, states that engines are to be overhauled at least every twelve years. ## Factual narrative On December 9, 2006, at 1430 central standard time, a Cessna 140, N76379, owned and piloted by a private pilot, received substantial damage on impact with terrain during a forced landing on a farm field near Vienna, Missouri. The pilot stated that the engine lost power after he heard a "bang." Visual meteorological conditions prevailed at the time of the accident. The pilot reported no injuries. The flight last departed from Rolla National Airport (VIH) Rolla/Vichy, Missouri, at 1410. The pilot purchased the airplane and had taken delivery of it at VIH on the day of the accident. The airplane was powered by a Continental C-85-12F engine, serial number 25578-6-12, which according to logbook entries, was last overhauled on July 25, 1990, and accumulated a total time since overhaul of 257.5 hours. A disassembly examination of the engine at Teledyne Continental Motors, Mobile, Alabama, revealed three of the crankshaft cluster gear bolts were fractured through. The bolt fracture surface features were consistent with fatigue. Additionally, the crankshaft gear had a hole where a crankshaft dowel was later installed following a design change in 1948 and was reflected in subsequent maintenance manuals. The dowel is used as a reference in machining the crankshaft. During the disassembly, the tappets fell out when the engine was overturned during the disassembly. It was later noted that the tappets did not contain retaining hardware. The interior of the crankcase halves contained a black colored residue when the oil was drained. Teledyne Continental Service Information Letter, SIL98-9A, Time Between Overhaul Periods, states that engines are to be overhauled at least every twelve years. ## Aircraft - Registration: [N76379](https://openairdocs.org/aircraft/N76379), registered now, S/N 10800, built 1946 (OpenAirDocs) - Reported make and model: Cessna 140 - Registry model: [Cessna 140](https://openairdocs.org/model/cessna-140) (registry code 2071602) (OpenAirDocs) - Registry engine: [Continental C85 series](https://openairdocs.org/engine/continental-c85-series) (registry code 17008, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 10800 - Airframe hours: 3154 - Engines: Continental C85-12F 85 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal; Standard, Utility - Last inspection: 100 hour, December 1, 2006, 3.3 hours before - Departed: VIH, Rolla/Vichy, MO - Destination: K34, Gardner, KS ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 56; injuries: none; private; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 3, with waivers/limitations; last flight review July 1, 2006; seat: left; flight hours: 492 total, 6 in this make and model, 431 as pilot in command, 40 in the last 90 days, 28 in the last 30 days, 6 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 220° at 13 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 46 °F, dew point 25 °F - Altimeter: 30.22 inHg - Observed at: VIH, 13 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 20061209029099A](https://openairdocs.org/incident/20061209029099A), Dec 9, 2006: Cessna 140, Vienna, MO, Substantial damage. (-23) The pilot stated approximately 10 minutes after takeoff from the rolla national (vih) airport that he heard a loud bang and the engine lost power. He… ## Other investigations on N76379 (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 ATL83FKQ02](https://openairdocs.org/ntsb/ATL83FKQ02), May 10, 1983: Cessna 140 (N76379), New Albany, MS, substantial damage 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.