# NTSB IAD97LA002: Cessna 150H, N6741S, Sunbury, PA, October 5, 1996 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: October 5, 1996, 13:15 local (17:15 UTC) - Place: Sunbury, PA - Coordinates: 40.859214, -76.779853 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=40.8592&lon=-76.7799&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report March 31, 1998 - Report: Approved by Office Director - NTSB case key (mKey): 28147 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=IAD97LA002 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/28147/pdf - Page: https://openairdocs.org/ntsb/IAD97LA002 ## Probable cause failure of the cluster gear attaching bolts (of which one failed from fatigue), resulting in a disconnect of the gear and loss of engine power. An obstruction (rock) in the emergency landing area was a related factor. ## 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 - miscellaneous,bolt/nut/fastener/clamp/spring - fatigue (cause) - accessory drive assy,drive gear - not connected (cause) - Forced landing, emergency descent/landing - Nose over, emergency landing - terrain condition - open field - terrain condition - rock(s)/boulder(s) (contributing factor) ## Analysis The pilot reported that the engine lost power while climbing through 2200 msl. He stated that his attempts to restart the engine, using the emergency procedures, were unsuccessful. During a forced landing in a field, the airplane struck a rock and nosed over. The airplane was examined after the accident by an FAA inspector. The examination revealed that the four bolts that held the crankshaft cluster gear to the crankshaft had failed. The accessory gear box cover was removed and the cluster gear rotated freely. Examination of the four bolts revealed that one of the bolts failed due to fatigue in the threaded area. (Due to smearing, failure mode of the the other 3 bolts was not determined). The engine had over 356 hours since overhaul. The pilot stated that he was unsure why the prior owner had the engine overhauled. ## Factual narrative On October 5, 1996, at about 1300 eastern daylight time (EDT), N6741S, a Cessna 150H, lost engine power and made a forced landing in a cornfield near Selinsgrove, Pennsylvania. The certificated commercial pilot, the sole occupant, reported no injuries. The airplane sustained substantial damage when it nosed over during the landing roll. Visual meteorological conditions prevailed and a flight plan was not filed. The personal flight originated in Selinsgrove, Pennsylvania, at 1250 EDT. The destination was Shamokin, Pennsylvania. The pilot reported that about 10 minutes after departure as the airplane was climbing through 2200 feet msl, the engine lost power. His attempts to restart the engine using the emergency procedures were unsuccessful. He stated that he made a forced landing in a farmers field, and during the landing the airplane nosed over. The airplane was examined after the accident by a Federal Aviation Administration Safety Inspector. The Inspector stated that the examination revealed that the four bolts that hold the crankshaft cluster gear to the crankshaft were missing. The accessory gear box cover was removed and the cluster gear rotated freely. The Inspector stated that the bolts were removed and it was revealed that one of the bolts failed due to fatigue in the threaded area. According to the Inspector the engine had over 356 hours since overhaul, and the pilot/owner reported that the prior owner had the engine overhauled prior to his purchase. ## Aircraft - Registration: [N6741S](https://openairdocs.org/deregistered/N6741S-2013-02-13), registration cancelled 2013-02-13, S/N 15067541, built 1967 (OpenAirDocs) - Reported make and model: Cessna 150H - Registry model: [Cessna 150H](https://openairdocs.org/model/cessna-150h) (registry code 2071818) (OpenAirDocs) - Registry engine: [Continental 0-200 series](https://openairdocs.org/engine/continental-0-200-series) (registry code 17020, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 150-67541 - Airframe hours: 2450 - Engines: Continental O-200-A 100 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: John Bakowicz - Airworthiness certificate: Standard, Utility - Last inspection: Annual, April 7, 1996, 85 hours before - Departed: SEG, SELINSGROVE, PA - Destination: N79, SHAMOKIN, PA ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 51; commercial; airplane ratings: multi-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; seat: left; flight hours: 1,312 total, 1,093 as pilot in command, 48 in the last 90 days, 9 in the last 30 days, 2 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 200° at 7 knots - Visibility: 20 statute miles - Lowest ceiling: none - Temperature: 54 °F, dew point 34 °F - Altimeter: 30.00 inHg - Observed at: UNV, 50 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 19961005047349A](https://openairdocs.org/incident/19961005047349A), Oct 5, 1996: Cessna 150H, Sunbury, PA, Substantial damage. (-16) The airworthiness of the engine was compromised by reusing the same crankshaft cluster gear bolts (p/n 22532) at overhaul, although no requirement exists… 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.