# NTSB FTW95LA117: Cessna 172RG, N5096U, Plano, TX, February 17, 1995 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: February 17, 1995, 12:35 local (18:35 UTC) - Place: Plano, TX - Coordinates: 33.060909, -96.729782 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=33.0609&lon=-96.7298&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report August 23, 1995 - Report: Approved by Office Director - ADs cited in the narratives: [AD 91-14-22](https://openairdocs.org/ad/91-14-22) (OpenAirDocs) - NTSB case key (mKey): 19354 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW95LA117 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/19354/pdf - Page: https://openairdocs.org/ntsb/FTW95LA117 ## Probable cause THE DISENGAGEMENT OF THE CRANKSHAFT GEAR DUE TO THE LOOSENING OF THE GEAR RETAINING BOLT AND THE SUBSEQUENT FRACTURE OF THE GEAR ALIGNMENT DOWEL. A FACTOR WAS THE LACK OF SUITABLE TERRAIN AVAILABLE FOR THE FORCED LANDING. ## 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, descent - normal - miscellaneous,bolt/nut/fastener/clamp/spring - loose (cause) - miscellaneous,dowel/pin - fractured (cause) - engine assembly,gear - disengaged (cause) - Forced landing, descent - emergency - Nose over, emergency landing - terrain condition - none suitable (contributing factor) - terrain condition - soft ## Analysis WHILE DESCENDING EN ROUTE, THE ENGINE LOST POWER AND A FORCED LANDING WAS MADE IN A PLOWED FIELD. THE NOSE WHEEL SEPARATED AND THE AIRPLANE NOSED OVER COMING TO REST INVERTED. DISASSEMBLY OF THE ENGINE REVEALED A LOSS OF GEAR TRAIN CONTINUITY DUE TO THE LOOSENING OF THE CRANKSHAFT GEAR RETAINING BOLT AND THE SUBSEQUENT FRACTURE OF THE CRANKSHAFT GEAR ALIGNMENT DOWEL. THE AIRPLANE'S PROPELLER HAD BEEN REPLACED ON 02/13/92 FOLLOWING A NOSE GEAR COLLAPSE; HOWEVER, AD 91-14-22 WAS NOT COMPLIED WITH AS THE ENGINE DID NOT EXPERIENCE SUDDEN STOPPAGE. ## Factual narrative On February 17, 1995, at 1235 central standard time, a Cessna 172RG, N5096U, was substantially damaged during a forced landing near Plano, Texas. The commercial pilot and his passenger were not injured. Visual meteorological conditions prevailed for the repositioning flight from McKinney, Texas, to Addison, Texas. The airplane was in a descent 7 miles northeast of Addison Airport when the engine lost power. After attempting unsuccessfully to restart the engine, the pilot landed in a plowed field. According to the pilot, when the nose wheel touched down in the soft dirt it "dug in and broke off" and the "airplane performed a forward somersault and came to rest inverted." A Federal Aviation Administration inspector reported that the right wing spar was bent and the upper portions of the vertical stabilizer and rudder were crushed. Examination and disassembly of the engine on 03/06/95 revealed a lack of gear train continuity. The crankshaft gear lockplate tang was sheared and the crankshaft gear retaining bolt had backed out of the crankshaft to the point where no threads were engaged. The crankshaft gear alignment dowel was fractured. An examination of the aircraft logbooks by a Federal Aviation Administration inspector revealed that the propeller had been replaced on 02/13/92 following a nose gear collapse. Airworthiness Directive (AD) 91-14-22 was not complied with at that time. The AD requires an inspection of the crankshaft gear following any propeller strike which results in sudden engine stoppage. According to the operator, the nose gear collapse did not result in sudden engine stoppage. ## Aircraft - Registration: [N5096U](https://openairdocs.org/deregistered/N5096U-1995-11-01), registration cancelled 1995-11-01, S/N 172RG0230 (OpenAirDocs) - Reported make and model: CESSNA 172RG - Registry model: [Cessna 172RG](https://openairdocs.org/model/cessna-172rg) (registry code 2072438) (OpenAirDocs) - Category: Airplane - Serial number: 172RG0230 - Airframe hours: 3976 - Engines: LYCOMING O-360-F1A6 180 horsepower reciprocating - Damage: Substantial damage - Flight: Positioning, Part 91 - Operator: Menagerie Enterprises, doing business as Monarch Air - Registered owner: Zappolo, Richard A. - Airworthiness certificate: Standard, Normal - Last inspection: Annual, July 24, 1994, 26 hours before - Departed: TKI, MCKINNEY, TX - Destination: ADS, ADDISON, TX ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 22; flight instructor, commercial; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, valid medical--w/ waivers/lim; seat: left; flight hours: 700 total, 20 in this make and model, 629 as pilot in command, 6 in the last 90 days, 1 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 300° at 7 knots - Visibility: 12 statute miles - Lowest ceiling: none - Temperature: 50 °F, dew point 28 °F - Altimeter: 30.00 inHg ## 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 19950217002199A](https://openairdocs.org/incident/19950217002199A), Feb 17, 1995: Cessna 172RG, Plano, TX, Substantial damage. Lost power descending en route. Landed plowed field. Nosed over. Crankshaft gear bolt loosened, dowell fractured. 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.