ANC05LA097 · Helio H-250
Helio H-250 · Accident: airframe, component or system failure during landing
From Merrill Field (MRI) to Merrill Field (MRI)
Event
- NTSB case
- ANC05LA097
- 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
Helio H-250
- Aircraft type
- Helio H-250
- 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
- N333TB
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Merrill Field (MRI), Anchorage, AKTo Merrill Field (MRI), Anchorage, AK
- 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 91: General Aviation
- 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
- Landing · landing roll
- 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
- Airframe, component or system failure
- 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, main gear strut › Fractured
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
The first pilot, a certificated flight instructor, was providing flight instruction and recurrent training to the second pilot, a certificated private pilot. The first pilot said that after an uneventful touchdown on the dry and paved asphalt runway, a loud shuddering noise was heard as the second pilot applied the brakes. As the landing roll continued, the right main landing gear collapsed, and the right wing struck the runway. The airplane sustained structural damage to the right wing. A postaccident review of the fractured right main landing gear leg assembly in the fracture zone, disclosed brownish rust-colored deposits that covered about 1/4 of the circumference of the main landing gear tube. The remaining 3/4 circumference of the main landing gear tube had a 45-degree sheer lip, with the fracture surfaces consistent with an overload failure.
Probable cause
A fracture failure of the main landing gear leg during the landing roll, which resulted in the collapse of the main landing gear.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record ANC05LA097
- Event ID
- 20050718X01049
- Case number
- ANC05LA097
- 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: local date, investigation status, coordinates. Values present in the bulk record are kept.
- The date is the local date; the NTSB stores the UTC date 2005-07-07.
- API snapshot SHA-256: 6c6b91dbdb2ee9eb90234611aa934a6ff9a6f139d68d08fab519d6bbd050d2bf; retrieved 2026-09-22T05:40:15.579Z.