Hughes 369D accident near Blair, Wisconsin, March 7, 2018
On March 7, 2018 at about 8:00 pm local time, a 1979 Hughes 369D (helicopter), registered N499SL, was involved in an accident during maneuvering (hover) near Blair, Wisconsin. It was an external-load flight under external-load helicopter rules (Part 133). 1 person was seriously injured; 1 other was unhurt. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The pilot’s failure to recognize and compensate for hazards during the external load operation, which led to a collision between a lineman (external load) and a powerline.
Source: NTSB aviation accident database, copy made November 2, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- March 7, 2018 · about 8:00 pm local time · cases in 2018
- Place
- Blair, Wisconsin · map
- Type
- Accident
- Injuries
- 1 person was seriously injured; 1 other was unhurt.
- Weather
- visual conditions (good weather)
- Aircraft
- Hughes 369D D, built 1979 · all 369Ds on the register
- Registration
- N499SL · registry record · serial 190448D
- Damage
- Not recorded
- Flight
- External-load flight · external-load helicopter rules (Part 133)
The NTSB's narrative final · quoted from the NTSB record
The commercial pilot of the helicopter reported that the purpose of the flight was to lift a utility company lineman to a structure to perform work in conjunction with a new powerline project. While transporting the lineman to the structure using a long line, the worker contacted an existing, live powerline and was seriously injured. The weather conditions at the time of the accident included 10 miles visibility and no precipitation. The pilot reported that he could not see the powerline from his perspective until it was too late to make a course change. The pilot recommended that better recognition of hazards and obstructions may have prevented the accident.
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
- Miscellaneous/other during maneuvering (hover) defining event
- Collision with terrain or object (not controlled flight into terrain) during maneuvering (hover)
The NTSB's findings
- cause Personnel issues › Task performance › Planning/preparation › Flight planning/navigation › Pilot
- cause Personnel issues › Action/decision › Info processing/decision › Identification/recognition › Pilot
Pilot
- Certificate: commercial pilot
- Ratings: single-engine land; instructor: helicopter; instructor: instrument helicopter; instrument: helicopter; rotorcraft: helicopter
- Flight time: 5,350 hours in all; 3,900 in this make and model; 300 in the last 90 days; 100 in the last 30 days; 5,250 as pilot in command; 199 on instruments
- Medical certificate: Class 2 (without waivers/limitations)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 18,746 hours
- Last inspection: 100-hour inspection, February 24, 2018
- Maximum gross weight: 3,000 lb
- Landing gear: fixed
- Engine: Rolls Royce C20B (turboshaft); 420 hours total
The flight
- Departed from: Blair WI
- Destination: Blair WI
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 290° at 9 knots, gusting 14
- Visibility: 10 statute miles
- Sky: broken clouds at 3,700 ft
- Temperature: 28°F (-2°C), dew point 10°F (-12°C)
- Altimeter: 29.97 inHg
- Observation at 7:55 pm from BCK, 17 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
1 document, released by the NTSB on June 25, 2018. View them here, or download them; the NTSB redacts some personal details before release, and this site shows the NTSB's own titles rather than its file names.
| # | Document | What it is | |
|---|---|---|---|
| 1 | Pilot/operator Aircraft Accident Report, NTSB Form 6120.1 | PDF, 9 pages | View Download |
The same docket at the NTSB · documents without a copy here are fetched from the NTSB when you open them.
Connections how this case links to the rest of the register
- N499SL on the register today · the tail number may have moved to another aircraft since
- Hughes 369 500 series helicopters 124 registered today · the model family and its accident history
- Hughes 387 aircraft on the register
- Engine: Rolls Royce C20B · as the NTSB recorded it
- Accidents and incidents in Wisconsin 1,622 since 1982 · 226 in the last ten years
- Wisconsin 6,164 aircraft registered
The whole map of how records connect · these connections as data: /graph/accident/CEN18LA121.json.
The bigger picture in Aviation Analytics: accidents over time since 1982, by model, by phase of flight and conditions, by place and on the map.
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 does not name anyone involved, its policy at this time. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.