GAA16CA480 · Hughes 369 D
Air2 Hughes 369 D · Accident while maneuvering
Event
- NTSB case
- GAA16CA480
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Accident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- API-reported fatalities
- 0 · all aircraft and ground
- Ground fatalities
- Unknown
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- General aviation
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Visual Meteorological Cond
Hughes 369 D
- Aircraft type
- Hughes 369
- Category
- Helicopter
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N500TN
- Operator
- AIR2
- Onboard fatalities
- Unknown
- Route
- From not recordedTo not recorded
- Aircraft age
- About 37 years (built 1979)
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 133: Rotorcraft Ext. Load
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- Maneuvering · hover
- Defining eventThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- Miscellaneous/other
- Also codedOther events the NTSB coded in the sequence, such as a wire strike after a loss of power. Flight Findings uses them for its kinds of event. Glossary
- Wire
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Substantial
Cause areas
- Environmental issues › Physical environment
- Personnel issues › Psychological
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The helicopter pilot reported that he was flying in support of a utility company crew that was installing line guards for a conductor damper on an energized 161 kilovolts (Kv) electrical transmission line. The transmission line had three phases (power lines) that were separated vertically and staggered horizontally from one another and ran parallel to the ground. The lower phase power line was about 9.5 ft (horizontally) further out from the middle phase power line. While the helicopter was approaching the lines, its main rotor blade clearance from the middle phase line was about 2.5 ft, which resulted in an electrical arc to the main rotor. The pilot landed the helicopter away from the transmission line without further incident.
A postaccident examination revealed substantial damage to the main rotor hub and two main rotor blades.
The pilot reported no preaccident mechanical malfunctions or failures with the helicopter that would have precluded normal operation.
According to Occupational Safety & Health Administration 1910.269(I)(10), the minimum approach distance (MAD) is to "ensure that workers do not approach or take any conductive object closer to the energized parts as set forth in the table below (excerpt)." For a voltage of 161 Kv, the MAD for this operation was equal to or greater than 4.00625 ft.
Probable cause
The helicopter pilot’s failure to maintain sufficient separation between the main rotor blade and a power line during line guard installation, which resulted in an electrical arc to the main rotor.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record GAA16CA480
- Event ID
- 20160913X75516
- Case number
- GAA16CA480
- Dataset
- full-current
- Source SHA-256
- 5cf380f0061817c0331a6b2d8cc7e0ee3a79bea469a1001dc5c10e56f35f5ab3
Source notes (4)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: investigation status. Values present in the bulk record are kept.
- The date is the local date, which is the same as the UTC date the NTSB stores.
- API snapshot SHA-256: 0673e92314a093a27535205a832896f910767b94ab02d5211bb8653a98a6d910; retrieved 2026-09-16T04:15:46.794Z.