ANC99LA141 · Eurocopter AS-350B-2
Eurocopter AS-350B-2 · Accident: in flight collision with terrain/water en route
From JUN · AK to an unrecorded destination
Event
- NTSB case
- ANC99LA141
- 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
- N6099Y
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From JUN · 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
- 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 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 en route from Petersburg to Juneau, when he was requested to join a search for an overdue company helicopter (N6007S). He said that just after entering the search area, he received a radio transmission from another company helicopter (N6052C), who was also involved in the search. The pilot of N6052C informed him that he had crashed on the ice field, and required assistance. The pilot of N6099Y stated that poor weather conditions in the vicinity N6052C would not allow the him to land, so he elected to return to the airport for fuel, and wait for better weather conditions. After refueling, he returned to the accident site of N6052C, where weather conditions had improved. After landing, the uninjured pilot and passenger boarded N6099Y, and all aboard agreed to continue the search for N6007S. The pilot of N6099Y stated that he was able to locate the downed helicopter about two miles directly in front of his location. He said that he slowed the helicopter to about 30 knots in an attempt to gain reference using a mountain range on the left side of the helicopter, and the accident site of N6007S. He said: 'The ceiling at my location was at least 1,000 feet agl, and visibility towards 07S was more than six miles. Just before the impact, I was sure I was at least 500 feet agl.' The pilot added that 'flat light conditions' hampered his ability to see the topographical features of the ice field below. The helicopter struck the snow-covered ice field, slid about 50 feet, nosed over, and rolled to the left. The helicopter sustained substantial damage to the fuselage, tail boom, and rotor system. The accident 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 ANC99LA141
- Event ID
- 20001212X19667
- Case number
- ANC99LA141
- 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 1999-09-11.
- API snapshot SHA-256: 814489418560bcc7c1fc5315423a0a71163ec5c559eb43fd3ee48f7645a59a84; retrieved 2026-09-22T14:10:38.043Z.