# NTSB WPR15LA116: Bell 47G 2A, N4774S, Ivanhoe, CA, February 27, 2015 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Limited investigation · Final report - Date: February 27, 2015, 10:30 local (18:30 UTC) - Place: Ivanhoe, CA - Coordinates: 36.459445, -119.190834 - Nearby events: https://openairdocs.org/map.md?lat=36.4594&lon=-119.1908&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering-low-alt flying: Abrupt maneuver](https://openairdocs.org/ntsb-events/270) - Highest injury: Serious injuries - Injuries: 1 serious - Status: Completed, report September 6, 2017 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: FAA - NTSB case key (mKey): 90794 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR15LA116 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/90794/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=90794 - Page: https://openairdocs.org/ntsb/WPR15LA116 ## Probable cause The pilot’s failure to maintain clearance from a power line while maneuvering at low altitude. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Object/animal/substance: wire](https://openairdocs.org/ntsb-findings/03022032): Environmental issues › Physical environment · Decision related to condition (probable cause); cases with it: [Bell 47G-2A, 2 cases](https://openairdocs.org/ntsb-findings/03022032/cases.md?model=1181012), [All aircraft, 588 cases](https://openairdocs.org/ntsb-findings/03022032/cases.md) - [Performance/control parameters: altitude](https://openairdocs.org/ntsb-findings/01062012): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Bell 47G-2A, 2 cases](https://openairdocs.org/ntsb-findings/01062012/cases.md?model=1181012), [All aircraft, 1,310 cases](https://openairdocs.org/ntsb-findings/01062012/cases.md) - [Info processing/decision: decision making/judgment](https://openairdocs.org/ntsb-findings/02041520): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Bell 47G-2A, 2 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md?model=1181012), [All aircraft, 3,098 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md) - [Object/animal/substance: wire](https://openairdocs.org/ntsb-findings/03022032): Environmental issues › Physical environment · Effect on operation (probable cause); cases with it: [Bell 47G-2A, 2 cases](https://openairdocs.org/ntsb-findings/03022032/cases.md?model=1181012), [All aircraft, 588 cases](https://openairdocs.org/ntsb-findings/03022032/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: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Bell 47G-2A, 7 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=1181012), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) - [Maneuvering-low-alt flying: Abrupt maneuver](https://openairdocs.org/ntsb-events/270) (defining event); cases with it: [Bell 47G-2A, 1 case](https://openairdocs.org/ntsb-events/270/sequence.md?model=1181012), [All aircraft, 346 cases](https://openairdocs.org/ntsb-events/270/sequence.md) ## Analysis The commercial pilot was maneuvering the helicopter at low altitude to conduct agricultural spraying operations. While departing the coverage area, the pilot saw power lines and attempted to fly underneath them, but the helicopter's main rotor mast struck a wire, and the helicopter subsequently collided with terrain. The pilot reported no mechanical failures or malfunctions with the helicopter that would have precluded normal operation. ## Factual narrative On February 27, 2015, at 1030 Pacific standard time, a Bell 47G 2A, N4774S, collided with a suspended power line 15 miles northeast of Ivanhoe, California. The helicopter was registered to Barton Aero, Inc., and operated by Gilbert Aviation as a 14 Code of Federal Aviation, Part 137 aerial application flight. The commercial pilot was seriously injured, and the helicopter was substantially damaged. Visual meteorological conditions prevailed, and a flight plan had not been filed. A Federal Aviation Administration (FAA) inspector who spoke to the pilot, stated that the pilot knew about the power line and attempted to avoid it at the last second by flying under it. The wire caught the main rotor mast and the helicopter came to rest on its right side in an orange tree orchard. The pilot was able to self extract, and sustained numerous broken bones. Examination of the helicopter wreckage by the inspector confirmed that a electrical power cable had wrapped around the helicopter's rotor mast. The pilot reported no mechanical failures or malfunctions with the helicopter that would have precluded normal operation. ## Aircraft - Registration: [N4774S](https://openairdocs.org/deregistered/N4774S-2018-03-15), registration cancelled 2018-03-15, S/N WAV182, built 1965 (OpenAirDocs) - Reported make and model: BELL 47G 2A - Registry model: [Bell 47G-2A](https://openairdocs.org/model/bell-47g-2a) (registry code 1181012) (OpenAirDocs) - Registry engine: [Lycoming VO-435 series](https://openairdocs.org/engine/lycoming-vo-435-series) (registry code 41525, reciprocating) (OpenAirDocs) - Category: Helicopter - Serial number: WAV182 - Year built: 1965 - Airframe hours: 4089 - Engines: LYCOMING VO-435 A1F 220 horsepower reciprocating - Damage: Substantial damage - Flight: Aerial application, Part 137 - Operator: Barton Aero Inc - Registered owner: Barton Aero Inc - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, January 11, 2015 - Departed: D86, VISALIA, CA - Destination: D86, VISALIA, CA ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 50; injuries: serious; commercial; airplane ratings: single-engine land; medical: class 2, unknown; seat: left; restraint: 4-point; flight hours: 4,920 total, 0 in the last 90 days, 0 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 6 statute miles - Lowest ceiling: none - Temperature: 59 °F, dew point 46 °F - Altimeter: 29.86 inHg - Observed at: KVIS, 15 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 20150227001849A](https://openairdocs.org/incident/20150227001849A), Feb 27, 2015: Bell 47G-2A, Ivanhoe, CA, Destroyed. While performing aerial application, the rotorcraft struck a power line and crashed in an orange grove. Just prior to the accident the PIC had noticed workers… ## Other investigations on N4774S (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 LAX03LA236](https://openairdocs.org/ntsb/LAX03LA236), Jul 20, 2003: Bell 47G-2A (N4774S), Porterville, CA, substantial damage. Probable cause: Fatigue-induced failure of bolts in the helicopter's rotor drive flange, which resulted in a total loss of torque to the rotor drive shaft. - [NTSB MIA77DLD51](https://openairdocs.org/ntsb/MIA77DLD51), Apr 19, 1977: EL Tomcat MK6A (N4774S), Lake Wales, FL, substantial damage ## Docket (3 files) The files NTSB released with the investigation on July 17, 2017, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=90794. 1.2 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 319 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40454295&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - FAA Inspector's Statement (item 2, .PDF, 128 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40454296&FileExtension=.PDF&FileName=FAA%20Inspector%27s%20Statement-Master.PDF - Photos (item 3, .PDF, 3 photos, 793 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40454297&FileExtension=.PDF&FileName=Photos-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.