Helio H-700 accident near Tok, Alaska, August 13, 1994
On August 13, 1994 at about 1:00 am local time, a Helio H-700, registered N4059H, was substantially damaged in an accident near Tok, Alaska. It was a flight of an unrecorded kind under charter and air-taxi rules (Part 135). No one was hurt; 4 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
THE PARTIAL FAILURE OF THE AIRPLANE'S NORMAL BRAKE SYSTEM.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- August 13, 1994 · about 1:00 am local time
- Place
- Tok, Alaska · map
- Type
- Accident
- Injuries
- No one was hurt; 4 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Helio H-700
- Registration
- N4059H · no longer on the register · serial 09
- Damage
- Substantial damage
- Flight
- Flight of an unrecorded kind · charter and air-taxi rules (Part 135)
The NTSB's narrative final · quoted from the NTSB record
AFTER LANDING ON THE GRAVEL BAR ON THE ROBERTSON RIVER, THE LEFT WHEEL'S BRAKE 'WENT SOFT.' THE PILOT ALLOWED THE AIRPLANE TO CONTINUE THE LANDING ROLL AND PRIOR TO STRIKING THE DITCH, HE INTENTIONALLY GROUND LOOPED THE AIRPLANE. DURING THE GROUND LOOP THE TAIL WHEEL STRUCK THE DITCH AND THE FUSELAGE BUCKLED. EXAMINATION OF THE AIRPLANE SHOWED THAT THE LEFT BRAKE'S TORQUE PLATE HAD SHEARED AND BROKEN THE BRAKE LINE.
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
Pilot
- Certificate: airline transport pilot
- Ratings: multi-engine land; single-engine land; single-engine sea; instrument: airplane
- Flight time: 12,000 hours in all; 2,000 in this make and model; 300 in the last 90 days; 40 in the last 30 days; 11,800 as pilot in command
- Medical certificate: Class 1 (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 1,160 hours
- Last inspection: 100-hour inspection, July 20, 1994; 30 hours since
- Maximum gross weight: 3,800 lb
- Seats: 4
- Landing gear: fixed
- Engine: Lycoming TIO-540 (piston); 0 hours total
- Operator: 40 Mile Air, LTD
The flight
- Departed from: TKJ AK at 7:30 pm
- Runway 0
Weather at the time
- Light: daylight
- Visibility: 30 statute miles
- Sky: broken clouds at 4,000 ft; not recorded
- Temperature: 61°F (16°C), dew point 0°F (-18°C)
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | |||
| Passengers | 3 |
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 N4059H 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.