ANC90LA045 · Aerospatiale SA-315B
Aerospatiale SA-315B · Accident: in flight encounter with weather en route
From DRIFT RIVER, AK to GRANITE POINT, AK
Event
- NTSB case
- ANC90LA045
- 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
- General aviation
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Instrument Meteorological Cond
Aerospatiale SA-315B
- Aircraft type
- Aerospatiale SA-315
- Category
- Helicopter
- 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
- N37903
- Operator
- NTHRN Geophysical of America
- Onboard fatalities
- Unknown
- Route
- From DRIFT RIVER, AKTo GRANITE POINT, 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
- En route · cruise
- 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
- In flight encounter with weather
- Also codedOther events the NTSB coded in the sequence, such as a wire strike after a loss of power. Flight Findings uses them for its kinds of event. Glossary
- Visual flight rules (VFR) flight into instrument meteorological conditions (IMC)
- 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
- Pilot in command › VFR flight into imc, inadvertent
Not plotted · Location withheld: coordinates are missing, conflicting, invalid, or have no accepted acquisition method. No substitute location has been invented.
NTSB narrative
THE PLT RPRTD THAT WHEN HE TOOK OFF, THERE WAS 1-1/2 TO 2 MI VIS WITH LIGHT SNOW. ABOUT 5 MIN LATER, HE ENCOUNTERED WHITEOUT CONDITIONS & INITIATED A LANDING. HOWEVER, THE HELICOPTER TOUCHDOWN HARD & THE MAIN ROTOR BLADES CONTACTED THE TAIL BOOM, WHICH RESULTED IN EXTENSIVE DAMAGE.
Probable cause
THE PILOT'S INADVERTENT FLIGHT INTO INSTRUMENT METEOROLOGICAL CONDITIONS (IMC). FACTORS RELATED TO THE ACCIDENT WERE: SNOW COVERED TERRAIN, ADVERSE WEATHER CONDITIONS, AND SPATIAL DISORIENTATION OF THE PILOT, DUE TO LACK OF VISUAL CURE DURING THE LANDING.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record ANC90LA045
- Event ID
- 20001212X22829
- Case number
- ANC90LA045
- 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. Values present in the bulk record are kept.
- The date is the local date; the NTSB stores the UTC date 1990-04-06.
- API snapshot SHA-256: adebe6e4502d95d2fc6ee6b4c0e3a5d4c34e2b9722dbaa5ff29c4edbda9cc48c; retrieved 2026-09-21T23:55:36.969Z.