# NTSB GAA17CA355: Bell UH1B, N6180A, Williams, CA, June 21, 2017 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: June 21, 2017, 08:40 local (15:40 UTC) - Place: Williams, CA - Coordinates: 39.201667, -122.153335 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=39.2017&lon=-122.1533&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering-low-alt flying: Miscellaneous/other](https://openairdocs.org/ntsb-events/900) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report August 22, 2017 - Report: Approved by Office Director - NTSB office: General Aviation Accidents - Parties: FAA - NTSB case key (mKey): 95413 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=GAA17CA355 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/95413/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=95413 - Page: https://openairdocs.org/ntsb/GAA17CA355 ## Probable cause The pilot’s failure to maintain clearance from transmission wires while maneuvering at a low altitude during an agricultural application flight. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Attention/monitoring: monitoring environment](https://openairdocs.org/ntsb-findings/02021545): Personnel issues › Psychological · Pilot (probable cause); cases with it: [Bell UH-1B, 1 case](https://openairdocs.org/ntsb-findings/02021545/cases.md?model=1181410), [All aircraft, 809 cases](https://openairdocs.org/ntsb-findings/02021545/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 UH-1B, 1 case](https://openairdocs.org/ntsb-findings/03022032/cases.md?model=1181410), [All aircraft, 588 cases](https://openairdocs.org/ntsb-findings/03022032/cases.md) - [Action: lack of action](https://openairdocs.org/ntsb-findings/02041030): Personnel issues › Action/decision · Pilot; cases with it: [Bell UH-1B, 1 case](https://openairdocs.org/ntsb-findings/02041030/cases.md?model=1181410), [All aircraft, 792 cases](https://openairdocs.org/ntsb-findings/02041030/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: Miscellaneous/other](https://openairdocs.org/ntsb-events/900) (defining event); cases with it: [Bell UH-1B, 1 case](https://openairdocs.org/ntsb-events/900/sequence.md?model=1181410), [All aircraft, 1,556 cases](https://openairdocs.org/ntsb-events/900/sequence.md) ## Analysis The helicopter pilot reported that, while maneuvering at a low altitude during an agricultural application flight, he "forgot to duck" for some nearby transmission wires. The tail rotor struck the transmission wires, and the helicopter impacted terrain. The helicopter sustained substantial damage to the tailboom. The pilot reported that there were no preaccident mechanical failures or malfunctions with the helicopter that would have precluded normal operation. ## Factual narrative The helicopter pilot reported that, while maneuvering at a low altitude during an aerial application flight, he "forgot to duck" for some nearby transmission wires. The tail rotor struck the transmission wires and the helicopter impacted terrain. The helicopter sustained substantial damage to the tailboom. The pilot reported that there were no preaccident mechanical failures or malfunctions with the helicopter that would have precluded normal operation. ## Aircraft - Registration: [N6180A](https://openairdocs.org/aircraft/N6180A), registered now, S/N 62-1994, built 1962 (OpenAirDocs) - Reported make and model: BELL UH1B - Registry model: [Bell UH-1B](https://openairdocs.org/model/bell-uh-1b) (registry code 1181410) (OpenAirDocs) - Registry engine: [Lycoming T-53 series](https://openairdocs.org/engine/lycoming-t-53-series) (registry code 41549, reciprocating) (OpenAirDocs) - Category: Helicopter - Serial number: 62-1994 - Year built: 1962 - Airframe hours: 15178 - Engines: LYCOMING T-53-13B 1500 horsepower turbo shaft - Damage: Substantial damage - Flight: Aerial application, Part 137 - Operator: Jones Aviation Inc - Registered owner: Jones Aviation Inc - Airworthiness certificate: Special, Restricted (Special); Standard, Normal - Last inspection: 100 hour, April 18, 2017 - Equipment: Data recorder ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 62; injuries: none; commercial; airplane ratings: multi-engine land; medical: class 2, with waivers/limitations; last flight review October 3, 2015; seat: right; restraint: 4-point ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 82 °F, dew point 61 °F - Altimeter: 29.75 inHg - Observed at: KMYV, 28 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 20170621008579A](https://openairdocs.org/incident/20170621008579A), Jun 21, 2017: Bell UH-1B, Williams, CA, Substantial damage. Pilot struck wires during field application ## Docket (3 files) The files NTSB released with the investigation on July 27, 2017, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=95413. 1.0 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 819 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40454619&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Memorandum for Record – Telephone Interview, Pilot (item 2, .PDF, 68 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40454620&FileExtension=.PDF&FileName=Memorandum%20for%20Record%20%E2%80%93%20Telephone%20Interview,%20Pilot-Master.PDF - Accident Photo (item 3, .PDF, 119 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40454621&FileExtension=.PDF&FileName=Accident%20Photo-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.