# NTSB ANC99LA140: Eurocopter AS-350B-2, N6052C, Juneau, AK, September 10, 1999 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: September 10, 1999, 14:45 local (22:45 UTC) - Place: Juneau, AK - Coordinates: 58.579227, -134.769973 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=58.5792&lon=-134.7700&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report August 10, 2000 - Report: Approved by Office Director - NTSB office: Alaska Regional Office - NTSB case key (mKey): 47401 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC99LA140 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/47401/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=47401 - Page: https://openairdocs.org/ntsb/ANC99LA140 ## 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. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight collision with terrain/water, maneuvering - altitude/clearance - not maintained, pilot in command (cause) - self-induced pressure, pilot in command (contributing factor) - light condition - other (contributing factor) - terrain condition - snow covered (contributing factor) ## Analysis 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. ## Factual narrative On September 10, 1999, about 1445 Alaska daylight time, a Eurocopter AS-350B-2 helicopter, N6052C, sustained substantial damage when it impacted the surface of the Juneau ice field, about 17 miles north of Juneau, Alaska, at 58.37.646 north latitude, 134.28.270 west longitude. The helicopter was being operated as a visual flight rules (VFR) search and rescue flight under Title 14, CFR Part 91, when the accident occurred. The helicopter was operated by Temsco Helicopters, Inc., Ketchikan, Alaska. The certificated commercial pilot and the one passenger aboard were not injured. Visual meteorological conditions prevailed at the time of departure, and company flight following procedures were in effect. The flight originated about 1345 from the Juneau International Airport, Juneau. During an interview with the National Transportation Safety Board investigator-in-charge on September 11, the pilot reported that he was conducting a search for an overdue company helicopter. The pilot said that while searching the upper portion of the ice field, deteriorating weather conditions to the north and east required that he proceed south, and down the ice field. He stated 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. ## Aircraft - Registration: [N6052C](https://openairdocs.org/deregistered/N6052C-2002-06-03), registration cancelled 2002-06-03, S/N 2586, built 1991 (OpenAirDocs) - Reported make and model: Eurocopter AS-350B-2 - Registry model: [Aerospatiale AS350 B2 ECUREUIL](https://openairdocs.org/model/aerospatiale-as350-b2-ecureuil) (registry code 8680813) (OpenAirDocs) - Registry engine: [Turbomeca ARRIEL-1SER](https://openairdocs.org/engine/turbomeca-arriel-1ser) (registry code 60030, turbo-shaft) (OpenAirDocs) - Category: Helicopter - Serial number: 2586 - Airframe hours: 3727 - Engines: Turbomeca ARRIEL D1D 732 horsepower turbo shaft - Damage: Substantial damage - Flight: Part 91 - Registered owner: Temsco Helicopters, Inc. - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, September 5, 1999, 18 hours before - Departed: JNU, AK - Flight plan: Company VFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 27; commercial; medical: class 2, valid medical--no waivers/lim.; seat: right; flight hours: 2,396 total, 1,537 in this make and model, 2,336 as pilot in command, 170 in the last 90 days, 47 in the last 30 days, 4 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 180° at 5 knots - Visibility: 6 statute miles - Lowest ceiling: 700 ft overcast - Temperature: 45 °F ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 19990910046619A](https://openairdocs.org/incident/19990910046619A), Sep 10, 1999: Snias AS350B2, Juneau, AK, No damage. (-23) Upon learning that his company had an overdue aircraft, Mr. Kunkel got another company pilot and took off from the helicopter pad in Juneau and initiated… ## Docket (2 files) The files NTSB released with the investigation on July 28, 2000, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=47401. 653 KB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 608 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40465863&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Supplement S (item 2, .PDF, 45 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40127285&FileExtension=.PDF&FileName=Supplement%20S-Master.PDF From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.