Hughes 369D accident near Fall Branch, Tennessee, December 21, 2011
On December 21, 2011 at about 9:15 pm local time, a Hughes 369D (helicopter), registered N500TN, was substantially damaged in an accident during enroute near Fall Branch, Tennessee. It was an aerial observation flight under general aviation rules (Part 91). No one was hurt; 1 person was on board or involved. The weather was instrument conditions (cloud, fog or low visibility).
The NTSB's probable cause their words, unchanged
The pilot's improper decision to continue a visual flight into instrument meteorological conditions, which resulted in a wire strike.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- December 21, 2011 · about 9:15 pm local time
- Place
- Fall Branch, Tennessee · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- instrument conditions (cloud, fog or low visibility)
- Aircraft
- Hughes 369D · all 369Ds on the register
- Registration
- N500TN · registry record · serial 590521D
- Damage
- Substantial damage
- Flight
- Aerial observation flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
Prior to departure on a positioning flight, the pilot checked the weather and determined that visual meteorological conditions existed at both his departure and destination airports. However, while the pilot was following a highway in cruise flight at 400 feet above ground level, the ceiling rapidly became lower, and the pilot encountered instrument meteorological conditions. Moments later, while cruising at an airspeed of 65 knots, the pilot saw marker balls, which indicated that power lines were directly in front of the helicopter. The pilot lowered the collective and entered a right diving turn in order to avoid the wires, but one of the main rotor blades made contact. The rotor speed remained within limits, but the helicopter began to vibrate, so the pilot decided to land in a nearby field. Postaccident examination of the helicopter revealed that the main rotor blade that had made contact with the power line was substantially damaged.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The factual record from the NTSB's investigation tables, in plain English
What happened, in order
- VFR encounter with IMC during enroute defining event
- Controlled flight into terrain or object (CFIT) during enroute
The NTSB's findings
- cause Personnel issues › Action/decision › Info processing/decision › Decision making/judgment › Pilot
- Environmental issues › Physical environment › Object/animal/substance › Wire › Contributed to outcome
- Environmental issues › Conditions/weather/phenomena › Ceiling/visibility/precip › (general) › Effect on operation
Pilot
- Certificate: flight instructor, commercial pilot
- Ratings: instructor: helicopter; instructor: instrument helicopter; instrument: helicopter; rotorcraft: helicopter
- Flight time: 2,337 hours in all; 400 in this make and model; 220 in the last 90 days; 70 in the last 30 days; 2,387 as pilot in command; 1,200 on instruments
- Last flight review: January 21, 2011
- Medical certificate: Class 2 (without waivers/limitations)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 14,193 hours
- Last inspection: 100-hour inspection, December 5, 2011
- Maximum gross weight: 3,000 lb
- Seats: 4
- Landing gear: fixed
- Engine: Rolls-Royce 250-C20R/2 (turboshaft); 0 hours total
- Operator: Air 2 LLC
The flight
- Departed from: DXX Knoxville TN at 8:45 pm
- Destination: KTRI Blountville TN
Weather at the time
- Light: daylight
- Wind: from 230° at 10 knots
- Visibility: 1 statute miles
- Sky: overcast at 400 ft; not recorded
- Temperature: 61°F (16°C), dew point 57°F (14°C)
- Altimeter: 29.89 inHg
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), has not been read from the NTSB for this case yet; the list appears here once it has. Open the docket at the NTSB.
Other NTSB records under N500TN the same tail number, which may have belonged to a different aircraft at the time
Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.