Forty (40) Mile Air Helio H700 accident
Helio H700 · Accident: on ground/water collision with terrain/water during takeoff
From FINN CREEK, AK to Deadhorse Airport (SCC)
Event
- NTSB case
- ANC95LA039
- 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
- 0
- 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
- Charter & commuter
- 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
Helio H700
- Aircraft type
- Helio H700
- Category
- Airplane
- 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
- N4059H
- Operator
- Forty (40) Mile Air
- Onboard fatalities
- Unknown
- Route
- From FINN CREEK, AKTo Deadhorse Airport (SCC)
- Aircraft age
- Not recorded
- 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 135: Air Taxi & Commuter
- 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
- Takeoff
- First occurrenceThe 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
- On ground/water collision with terrain/water
- 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
- Landing gear, ski assembly › Overload
- Other maintenance personnel › Maintenance, installation, improper
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
THE PILOT, WITH THREE PASSENGERS, WAS DEPARTING A REMOTE AIRSTRIP ON THE RETURN PORTION OF AN ON-DEMAND CHARTER FLIGHT. THE AIRPLANE, EQUIPPED WITH WHEEL/SKIS, WAS BEING OPERATED WITH THE SKIS RETRACTED FROM A SNOW COVERED STRIP THAT WAS ABOUT 850 FEET LONG. DURING THE TAKEOFF ROLL, THE RIGHT MAIN LANDING GEAR SKI CONTACTED THE SNOW, SLOWING THE AIRPLANE'S ACCELERATION AND PRODUCING A PULL TO THE RIGHT. THE PILOT APPLIED LEFT RUDDER CONTROL AND LEFT BRAKE PRESSURE TO MAINTAIN DIRECTIONAL CONTROL. NEAR THE END OF THE TAKEOFF AREA, THE PILOT ROTATED THE AIRPLANE, HOWEVER, IT SETTLED SLIGHTLY AND THE RIGHT GEAR SKI TIP CONTACTED THE SNOW. THE RIGHT SKI MECHANISM WAS TORN FROM THE AIRPLANE. THE AIRPLANE BECAME AIRBORNE AND THE PILOT DECIDED TO PROCEED TO AN AIRPORT WHERE EMERGENCY RESCUE EQUIPMENT WAS AVAILABLE. DURING TOUCH DOWN AT THE DESTINATION RUNWAY, THE RIGHT MAIN GEAR COLLAPSED. THE FORWARD SKI LIMIT-CABLE BRACKET BOLTS WERE FOUND SHEARED. THREE OF THE BOLTS WERE NON-STANDARD HARDWARE INSTALLED BEFORE THE OPERATOR PURCHASED THE SKIS. THE LIMIT CABLE PREVENTS THE SKI TIP FROM PIVOTING DOWNWARD.
Probable cause
AN OVERLOAD FAILURE OF THE RIGHT MAIN GEAR RETENTION/LIMIT CABLE BRACKET BOLTS AND INSTALLATION OF NON-STANDARD BOLT HARDWARE BY OTHER MAINTENANCE PERSONNEL. THE PILOT'S FAILURE TO ABORT THE TAKEOFF WAS A FACTOR IN THE ACCIDENT.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record ANC95LA039
- Event ID
- 20001207X03056
- Case number
- ANC95LA039
- Dataset
- historical-pre2008
- Source SHA-256
- 89e2df6d848e7ab3b42e7d7c7a03ff403303057a26ca04c95b3ea67201c3ce74
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: 1e7d15d76fc7615f53bd962d26e597e52fd8b255b7e075154e24025045377547; retrieved 2026-09-18T18:02:18.561Z.