# NTSB CHI94LA314: Cessna 188B, N731SV, Oakdale, IL, September 7, 1994 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: September 7, 1994, 16:00 local (21:00 UTC) - Place: Oakdale, IL - Coordinates: 38.259571, -89.499412 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=38.2596&lon=-89.4994&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report May 16, 1995 - Report: Approved by Office Director - NTSB case key (mKey): 9668 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI94LA314 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/9668/pdf - Page: https://openairdocs.org/ntsb/CHI94LA314 ## Probable cause misalignment of the number one connecting rod during major overhaul. Factors were the subsequent scoring and fatigue failure of the crankshaft. ## 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, maneuvering - aerial application - engine assembly,crankshaft - scored (contributing factor) - engine assembly,crankshaft - fatigue (contributing factor) - maintenance,overhaul,major - improper, other maintenance personnel (cause) - Forced landing, emergency descent/landing - In flight collision with terrain/water, landing - flare/touchdown ## Analysis THE PILOT REPORTED A LOSS OF ENGINE POWER DURING HIS THIRD AERIAL APPLICATION SWATH RUN. DURING THE SUBSEQUENT FORCED LANDING, THE AIRPLANE SUSTAINED SUBSTANTIAL DAMAGE. EXAMINATION OF THE WRECKAGE REVEALED THE ENGINE WAS SEIZED AND THE CASE WAS FRACTURED IN THE VICINITY OF THE NUMBER ONE CYLINDER. NO EVIDENCE OF PREIMPACT AIRFRAME MALFUNCTION WAS DISCOVERED. EXAMINATION OF THE ENGINE REVEALED THE CRANKSHAFT WAS FRACTURED FORWARD OF THE NUMBER ONE CONNECTING ROD JOURNAL. IT WAS CONCLUDED THAT A FATIGUE FRACTURE RESULTED FROM A MISALIGNMENT AFTER A RECENT OVERHAUL WHICH CAUSED DAMAGED TO THE NUMBER TWO CRANKSHAFT CHEEK. ## Factual narrative On September 7, 1994, at 1600 central daylight time, a Cessna 188B, N731SV, operated by B D Flying Service of Virden, Illinois, sustained substantial damage during a forced landing near Oakdale, Illinois. The commercial pilot reported no injuries. Visual meteorological conditions prevailed for the 14 CFR Part 137 aerial application flight which originated in Sparta, Illinois, about 1530. No flight plan was filed. The pilot reported a loss of engine power during his third aerial application swath run. He said he attempted to land in a field and the airplane slid sideways, breaking the landing gear. The airplane sustained substantial damage to both wings and the fuselage. The pilot reported the total engine time was 1863.6 hours and the engine had 1835.7 hours at the time of overhaul. A Federal Aviation Administration (FAA) Inspector examined the wreckage and reported the engine was seized and the case was fractured in the vicinity of the number one cylinder. He reported no evidence of preimpact airframe malfunction. The FAA inspector said the engine was overhauled 27.9 flight hours prior to the accident. He provided the NTSB with an overhaul invoice which listed the part numbers of multiple after market engine components from Superior Airparts, Inc. He also provided a copy of a "yellow tag" for the crankshaft dated April 6, 1994. The engine was examined by the NTSB on November 18, 1995, at Teledyne Continental Motors, Mobile, Alabama. A large quantity of metallic debris was in the sump and oil screen. The crank case was fractured at the number one cylinder pad. The number one main bearing was severely galled. The number four and five rod bearings exhibited smeared metal deposits and discoloration. The crankshaft was fractured forward of the number one connecting rod journal. Inspection of the fracture revealed beach marks originating at a point at the bottom center of the connecting rod journal. The origin was smeared and located near a circumferential gouge next to the front face of the connecting rod. Dye penetrant inspection of the crankshaft revealed multiple cracks in the bearing surfaces forward of the fracture. An investigator from Teledyne Continental Motors concluded in his written report that "a misalignment problem existed after overhaul which resulted in damaging the number two crankshaft cheek just above the journal fillet. The damaged area initiated a fatigue fracture that progressed until separation." ## Aircraft - Registration: [N731SV](https://openairdocs.org/deregistered/N731SV-2006-08-10), registration cancelled 2006-08-10, S/N 18803127T, built 1978 (OpenAirDocs) - Reported make and model: CESSNA 188B - Registry model: [Cessna A188B](https://openairdocs.org/model/cessna-a188b) (registry code 2073005) (OpenAirDocs) - Registry engine: [Continental IO-520 series](https://openairdocs.org/engine/continental-io-520-series) (registry code 17032, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 18803127T - Airframe hours: 1863 - Engines: CONTINENTAL IO-520D 300 horsepower reciprocating - Damage: Substantial damage - Flight: Aerial application, Part 137 - Registered owner: B. D. Flying Service - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, February 15, 1994, 27 hours before - Departed: SAR, SPARTA, IL - Destination: 7H0, IL ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 34; commercial; airplane ratings: single-engine land, multi-engine land; medical: class 2, valid medical--no waivers/lim.; seat: center; flight hours: 6,000 total, 5,461 in this make and model, 5,925 as pilot in command, 94 in the last 90 days, 27 in the last 30 days, 5 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 15 statute miles - Lowest ceiling: none - Temperature: 84 °F ## 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 19940907026039A](https://openairdocs.org/incident/19940907026039A), Sep 7, 1994: Cessna 188B, Oakdale, IL, Substantial damage. Lost power on spray run. Crash landed. Engine was siezed. Case fractured. Misalignment problem from recent overhaul ## Other investigations on N731SV (2) 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 CHI05CA201](https://openairdocs.org/ntsb/CHI05CA201), Jul 26, 2005: Cessna 188 (N731SV), Mexico, MO, substantial damage. Probable cause: The pilot's failure to maintain directional control. Factors were the grass terrain adjacent to the runway and the collapse of the main landing gear. - [NTSB CHI80FEV39](https://openairdocs.org/ntsb/CHI80FEV39), Sep 23, 1980: Cessna 188 (N731SV), Mill Shoals, IL, 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.