# NTSB CEN11CA540: Bell 47G-2, N4771N, Charles City, IA, August 2, 2011 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Data collection · Final report - Date: August 2, 2011, 11:30 local (16:30 UTC) - Place: Charles City, IA - Coordinates: 43.072498, -92.610557 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=43.0725&lon=-92.6106&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) - Highest injury: Serious injuries - Injuries: 1 serious - Status: Completed, report October 17, 2011 - Report: Approved by Office Director - NTSB office: Central Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 81377 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN11CA540 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/81377/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=81377 - Page: https://openairdocs.org/ntsb/CEN11CA540 ## Probable cause The pilot's failure to refuel the helicopter which resulted in a loss of engine power due to fuel exhaustion. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Fluids: fuel](https://openairdocs.org/ntsb-findings/01071010): Aircraft › Fluids/misc hardware · Not serviced/maintained (probable cause); cases with it: [Bell 47G-2, 1 case](https://openairdocs.org/ntsb-findings/01071010/cases.md?model=1181008), [All aircraft, 1,695 cases](https://openairdocs.org/ntsb-findings/01071010/cases.md) - [Personnel issues](https://openairdocs.org/ntsb-findings/02060000): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Bell 47G-2, 1 case](https://openairdocs.org/ntsb-findings/02060000/cases.md?model=1181008), [All aircraft, 137 cases](https://openairdocs.org/ntsb-findings/02060000/cases.md) - [Fluids: fuel](https://openairdocs.org/ntsb-findings/01071010): Aircraft › Fluids/misc hardware · Fluid level (probable cause); cases with it: [Bell 47G-2, 1 case](https://openairdocs.org/ntsb-findings/01071010/cases.md?model=1181008), [All aircraft, 1,695 cases](https://openairdocs.org/ntsb-findings/01071010/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Maneuvering: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) (defining event); cases with it: [Bell 47G-2, 1 case](https://openairdocs.org/ntsb-events/341/sequence.md?model=1181008), [All aircraft, 3,820 cases](https://openairdocs.org/ntsb-events/341/sequence.md) - [Autorotation: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Bell 47G-2, 6 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=1181008), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The operator reported that prior to the accident flight the pilot was distracted during a refueling operation. The distraction involved ground personnel entering the helicopter cabin after landing to discuss the next spraying operation with the pilot. After the conversation, the pilot departed without refueling the helicopter. While completing an aerial application, the engine experienced a loss of engine power. The pilot initiated an autorotation, during which the helicopter impacted terrain. A postaccident examination of the helicopter revealed the tail boom was partially separated and the landing gear skids were bent. The operator reported that approximately 3.5 quarts of fuel were drained from the fuel tanks, and 2 gallons of fuel were considered unusable. ## Factual narrative The operator reported that prior to the accident flight, the pilot was distracted during his intended refueling operation. The distraction involved ground personnel entering the helicopter cabin after landing to discuss the next spraying operation with the pilot. After the conversation, the pilot departed without refueling the helicopter. While completing an aerial application, the engine experienced a loss of engine power. The pilot initiated an autorotation and impacted terrain. A postaccident examination of the helicopter showed the tail boom was partially separated and the landing gear skids were bent. The operator reported that approximately 3.5 quarts of fuel were drained from the fuel tanks, and 2 gallons of fuel were considered unusable. ## Aircraft - Registration: [N4771N](https://openairdocs.org/deregistered/N4771N-2017-09-06), registration cancelled 2017-09-06, S/N 2216, built 1958 (OpenAirDocs) - Reported make and model: BELL 47G-2 - Registry model: [Bell 47G-2](https://openairdocs.org/model/bell-47g-2) (registry code 1181008) (OpenAirDocs) - Registry engine: [Lycoming VO-435 series](https://openairdocs.org/engine/lycoming-vo-435-series) (registry code 41525, reciprocating) (OpenAirDocs) - Category: Helicopter - Serial number: 2216 - Engines: LYCOMING VO-435 SERIES 260 horsepower reciprocating - Damage: Substantial damage - Flight: Aerial application, Part 137 - Operator: Scotts Helicopter Services Inc - Registered owner: Scotts Helicopter Services Inc - Airworthiness certificate: Standard, Utility - Departed: Charles City, IA - Destination: Charles City, IA ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 54; injuries: serious; private, commercial; airplane ratings: single-engine land; instrument ratings: helicopter; medical: class 2, with waivers/limitations; last flight review June 1, 2011; seat: right; flight hours: 4,100 total, 3,000 in this make and model ## Weather - Conditions: Visual (VMC), Day ## 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 20110802020479A](https://openairdocs.org/incident/20110802020479A), Aug 2, 2011: Bell 47G-2, Charles City, IA, Substantial damage. As stated by the pilot, upon landing with the intention of refueling, he exited the aircraft and became distracted by ground personnel when they showed him a… ## Docket (1 files) The files NTSB released with the investigation on August 25, 2011, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=81377. 50 KB in all. - Record of Conversation - Operator (item 1, .PDF, 50 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40352917&FileExtension=.PDF&FileName=Record%20of%20Conversation%20-%20Operator-Master.PDF 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.