# NTSB WPR14CA115: Bell 47G 5A, N715BH, Greenfield, CA, February 18, 2014 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: February 18, 2014, 08:30 local (16:30 UTC) - Place: Greenfield, CA - Coordinates: 36.280834, -121.166946 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=36.2808&lon=-121.1669&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering-low-alt flying: Loss of visual reference](https://openairdocs.org/ntsb-events/402) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report April 23, 2014 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Adminstration - NTSB case key (mKey): 88809 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR14CA115 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/88809/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=88809 - Page: https://openairdocs.org/ntsb/WPR14CA115 ## Probable cause The pilot's failure to maintain clearance from a power pole during low-altitude maneuvering flight. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Object/animal/substance: pole](https://openairdocs.org/ntsb-findings/03022010): Environmental issues › Physical environment · Response/compensation (probable cause); cases with it: [Bell 47G-5A, 2 cases](https://openairdocs.org/ntsb-findings/03022010/cases.md?model=1181034), [All aircraft, 142 cases](https://openairdocs.org/ntsb-findings/03022010/cases.md) - [Attention/monitoring: task monitoring/vigilance](https://openairdocs.org/ntsb-findings/02021520): Personnel issues › Psychological · Pilot (probable cause); cases with it: [Bell 47G-5A, 1 case](https://openairdocs.org/ntsb-findings/02021520/cases.md?model=1181034), [All aircraft, 330 cases](https://openairdocs.org/ntsb-findings/02021520/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Maneuvering-low-alt flying: Loss of visual reference](https://openairdocs.org/ntsb-events/402) (defining event); cases with it: [Bell 47G-5A, 1 case](https://openairdocs.org/ntsb-events/402/sequence.md?model=1181034), [All aircraft, 242 cases](https://openairdocs.org/ntsb-events/402/sequence.md) - [Maneuvering-low-alt flying: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Bell 47G-5A, 3 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=1181034), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) - [Maneuvering-low-alt flying: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Bell 47G-5A, 1 case](https://openairdocs.org/ntsb-events/440/sequence.md?model=1181034), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) ## Analysis During the 2 hours leading up to the accident, the pilot of the agriculture and pest control category helicopter had sprayed about 40 acres of crops, having refueled once. He stated that during the last pass of his current field he misjudged the distance between the main rotor blades and a power pole. The main rotor blades struck the pole, and the pilot performed a forced landing into the field. During the landing, the helicopter rolled over, sustaining substantial damage to the firewall, tailboom, and cabin structure. The pilot reported no preimpact mechanical malfunctions or failures with the airframe or engine that would have precluded normal operation, and further stated that the accident could have been avoided if he had flown over the pole rather than attempting to fly around it. ## Factual narrative During the 2 hours leading up to the accident, the pilot of the agriculture and pest control category helicopter had sprayed about 40 acres of crops, having refueled once. He stated that during the last pass of his current field he misjudged the distance between the main rotor blades and a power pole. The main rotor blades struck the pole, and the pilot performed a forced landing into the field. During the landing, the helicopter rolled over, sustaining substantial damage to the firewall, tailboom, and cabin structure. The pilot reported no preimpact mechanical malfunctions or failures with the airframe or engine that would have precluded normal operation, and further stated that the accident could have been avoided if he had flown over the pole rather than attempting to fly around it. ## Aircraft - Registration: [N715BH](https://openairdocs.org/aircraft/N715BH), registered now, S/N 25105, built 1973 (OpenAirDocs) - Reported make and model: BELL 47G 5A (5A) - Registry model: [Bell 47G-5A](https://openairdocs.org/model/bell-47g-5a) (registry code 1181034) (OpenAirDocs) - Registry engine: [Lycoming VO-435-B1A](https://openairdocs.org/engine/lycoming-vo-435-b1a) (registry code 42201, reciprocating) (OpenAirDocs) - Category: Helicopter - Serial number: 25105 - Year built: 1973 - Airframe hours: 9400 - Engines: LYCOMING VO-435-B1A 265 horsepower reciprocating - Damage: Substantial damage - Flight: Aerial application, Part 137 - Operator: Wilbur-Ellis Co - Registered owner: Wilbur-Ellis Co - Airworthiness certificate: Special, Restricted (Special) - Last inspection: 100 hour, October 15, 2013, 2 hours before - Departed: KIC, KING CITY, CA - Destination: Greenfield, CA - Airport: KIC, King City ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 29; injuries: none; private, commercial; airplane ratings: single-engine land; medical: class 2, without waivers/limitations; last flight review February 1, 2013; seat: left; restraint: 4-point; flight hours: 768 total, 411 in this make and model, 685 as pilot in command, 13 in the last 90 days, 6 in the last 30 days, 2 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 46 °F, dew point 41 °F - Altimeter: 30.20 inHg - Observed at: SNS, 35 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 20140218002909A](https://openairdocs.org/incident/20140218002909A), Feb 18, 2014: Bell 47G-5A, Greenfield, CA, Substantial damage. Helicopter N715BH struck a power pole with its main rotor blade impacted ground and rolled over. ## Docket (4 files) The files NTSB released with the investigation on April 10, 2014, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=88809. 8.5 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 2.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40411127&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Photo 1. Power Pole (item 2, .PDF, 1.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40411128&FileExtension=.PDF&FileName=Photo%201.%20Power%20Pole-Master.PDF - Photo 2. Helicopter at Accident Site (item 3, .PDF, 2.8 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40411129&FileExtension=.PDF&FileName=Photo%202.%20Helicopter%20at%20Accident%20Site-Master.PDF - Photo 3. Helicopter at Accident Site (item 4, .PDF, 2.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40411130&FileExtension=.PDF&FileName=Photo%203.%20Helicopter%20at%20Accident%20Site-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.