# NTSB ATL95LA171: Bell 47G, N616X, Union City, TN, September 21, 1995 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: September 21, 1995, 14:15 local (19:15 UTC) - Place: Union City, TN - Coordinates: 36.419681, -89.050346 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=36.4197&lon=-89.0503&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report April 29, 1996 - Report: Approved by Office Director - NTSB case key (mKey): 3627 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ATL95LA171 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/3627/pdf - Page: https://openairdocs.org/ntsb/ATL95LA171 ## Probable cause Failure of a #4 connecting rod bolt, which resulted in engine stoppage and a 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, cruise - normal - engine assembly,connecting rod - failure (cause) - Forced landing, descent - emergency - autorotation - performed, pilot in command - Roll over, emergency landing ## Analysis During flight, the pilot noted a severe vibration and elected to make an emergency autorotation. He landed with forward speed in a flat, open, bean field. The pilot reported that during the landing, the skids got caught in the beans, and the helicopter rolled over. A cabin fire followed shortly thereafter. A postcrash engine teardown revealed that a #4 connecting rod bolt had failed, resulting in engine stoppage. ## Factual narrative On September 21, 1995, about 1415 central daylight time, a Bell 47G, N616X, force landed following an in-flight engine vibration, near Union City, Tennessee. The helicopter was operated by the pilot under the provisions of 14 CFR Part 91, and visual flight rules. Visual meteorological conditions prevailed. A flight plan was not filed for the solo, instructional flight. There were no injuries to the private pilot, and the helicopter was substantially damaged. Origination of the flight was Union City, Tennessee, about ten minutes prior to the accident. The pilot reported that while enroute to his farm, he noticed a vibration in the flight controls and initiated an autorotation. The pilot stated that he touched down in a flat bean field with forward speed. The skids caught on the beans, the helicopter rolled over, caught fire and burned. The pilot held a private pilot certificate with airplane single engine, multi engine, and instrument ratings. He also had a helicopter solo endorsement. During the ensuing engine teardown, it was noted that the connecting rod from the #4 cylinder was found separated from the crankshaft with the rod cap wedged between the rod and the case. Only 1 connecting rod bolt was located for the #4 cylinder, and it was located in the cap, with the threads stripped from the bolt. The separation of the rod resulted in the fracture of the camshaft, case cracking, and lifter separation. ## Aircraft - Registration: [N616X](https://openairdocs.org/deregistered/N616X-1997-03-06), registration cancelled 1997-03-06, S/N C5015 (OpenAirDocs) - Reported make and model: BELL 47G - Registry model: [Bell 47G](https://openairdocs.org/model/bell-47g) (registry code 1181002) (OpenAirDocs) - Category: Helicopter - Serial number: 5015 - Airframe hours: 1700 - Engines: FRANKLIN 6VS-335-A 210 horsepower reciprocating - Damage: Substantial damage - Fire: On-Ground - Flight: Instructional, Part 91 - Operator: Gordon Wade - Registered owner: Steven Terry Farms - Airworthiness certificate: Standard, Normal - Departed: UCY, TN ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 40; private; airplane ratings: multi-engine land; instrument ratings: airplane; medical: class 2, valid medical--no waivers/lim.; seat: left; flight hours: 1,475 total, 25 in this make and model ## Weather - Conditions: Visual (VMC), Day - Wind: 70° at 7 knots - Visibility: 7 statute miles - Lowest ceiling: none - Temperature: 75 °F, dew point 61 °F - Altimeter: 30.00 inHg - Observed at: DYR, 20 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 19950921029719A](https://openairdocs.org/incident/19950921029719A), Sep 21, 1995: Bell 47G, Union City, TN, Substantial damage. Vibration en route. Made run on landing in bean field. Skids tangled in beans. Rolled over. Connecting rod broken. ## Other investigations on N616X (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 DIA69D0078](https://openairdocs.org/ntsb/DIA69D0078), Sep 18, 1968: Bell 47G (N616X), Gaithersburg, MD, substantial damage - [NTSB UNK64X3113](https://openairdocs.org/ntsb/UNK64X3113), Jul 29, 1964: Bell 47G (N616X), Dublin, PA, 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.