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ANC99LA140 · Eurocopter AS-350B-2

10 Sept 1999 · Juneau, AK, United States

Eurocopter AS-350B-2 · Accident: in flight collision with terrain/water while maneuvering

From Juneau International Airport (JNU) to an unrecorded destination

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Event

NTSB case
ANC99LA140
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
Visual Meteorological Cond

Eurocopter AS-350B-2

Aircraft type
Eurocopter AS-350
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
N6052C
Operator
Unknown
Onboard fatalities
Unknown
Route
From Juneau International Airport (JNU), AKTo not recorded
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
Maneuvering
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 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

  • Pilot in command › Altitude/clearance, not maintained

Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.

NTSB narrative

The commercial helicopter pilot, with one passenger aboard, was conducting a search for an overdue company helicopter. While searching the upper portion of a glacial ice field, deteriorating weather conditions required the pilot to alter his search route. He said that he slowed the helicopter to 15 knots and attempted to use a mountain range on the right side of the helicopter for visual reference. He said: 'Visibility in front was enough to see all the way to the top of the Herbert (greater than three miles). The ceiling sloped down to the east 45 degrees with a height at the ridge of approximately 700 feet.' The pilot added that just seconds before the impact, he thought the helicopter was at least 500 feet above the surface. He said that 'flat light conditions' made it very difficult to see the topographical features of the ice field below. The helicopter struck the snow-covered ice field, slid about 75 feet, and the helicopter rolled over to the right. The helicopter sustained substantial damage to the fuselage, tail boom, and rotor system. After the accident, the pilot radioed for another company helicopter to pick them up. A second company helicopter, N6099Y, landed at the accident site, boarded the uninjured pilot and passenger, and continued the search. During the search, N6099Y also collided with the snow-covered ice field. See ANC99FA139, and ANC99LA141. The accident pilot did not possess an instrument rating, and the helicopter was not equipped with a radar altimeter.

Probable cause

The pilot's failure to maintain altitude/clearance. Factors associated with the accident were flat light conditions, snow-covered terrain, and self-induced pressure to continue the search.

Verbatim NTSB analysis and probable cause from the NTSB dataset

Sources

NTSB record ANC99LA140
Event ID
20001212X19666
Case number
ANC99LA140
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: 27610732e4bb4a4902d0ddf71208274fa1850cc3942dd51df59ebc1da3f6ef9a; retrieved 2026-09-22T14:10:52.880Z.