# NTSB ANC02LA068: Eurocopter France AS-350-B2, N197EH, Denali Park, AK, June 26, 2002 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: June 26, 2002, 11:15 local (19:15 UTC) - Place: Denali Park, AK - Coordinates: 61.209556, -149.249176 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=61.2096&lon=-149.2492&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Highest injury: Minor injuries - Injuries: 2 minor, 4 uninjured - Status: Completed, report April 1, 2003 - Report: Approved by Office Director - NTSB office: Alaska Regional Office - Parties: Federal Aviation Administration FSDO-03 - NTSB case key (mKey): 55076 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC02LA068 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/55076/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=55076 - Page: https://openairdocs.org/ntsb/ANC02LA068 ## Probable cause The pilot's failure to maintain aircraft control during takeoff, which resulted in dynamic rollover of the helicopter. A contributing factor was the frozen terrain. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of control - on ground/water, takeoff - aircraft control - not maintained, pilot in command (cause) - terrain condition - frozen (contributing factor) - Roll over, takeoff - aborted - dynamic rollover - encountered, pilot in command ## Analysis The pilot of the accident helicopter reported that he was attempting to takeoff from a glacier. During takeoff, he discovered the right landing gear skid was frozen to the surface of the glacier, and he decreased the collective control input. As he reduced the collective control input, the right skid broke free from the ice. He said that due to left cyclic input, when the right skid broke free from the ice, a left rolling moment was induced. The helicopter's main rotor blades subsequently contacted the surface of the glacier, and the helicopter rolled onto its right side. ## Factual narrative On June 26, 2002, about 1115 Alaska daylight time, a Eurocopter AS-350-B2 helicopter, N197EH, sustained substantial damage following a loss of control during takeoff from a glacier, about 40 miles east of Denali National Park, Alaska. The helicopter was being operated by Era Aviation, Inc., as a visual flight rules (VFR) on-demand charter flight under Title 14, CFR Part 135, when the accident occurred. The commercial pilot and one passenger received minor injuries; the four other passengers were not injured. Visual meteorological conditions prevailed, and a company VFR flight plan was in effect. During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC)on June 26, the pilot said he and the passengers had just completed a 20 minute glacier walk, and returned to the helicopter. He said they were going to depart the glacier as the third helicopter in a flight of three. He said as the first two helicopters passed by, he pulled up on the collective lever, and the left skid lifted up off the ice. He said as the left skid lifted off the ice , it exceeded the height where the right skid should have lifted off. He believed the right skid was frozen to the ice, so he started to reduce the collective input. The pilot said as he reduced the collective input, the right skid broke loose, and the helicopter rolled left. The main rotor blades struck the ice, and the helicopter flipped 180 degrees, coming to rest on its right side. In a subsequent written statement the operator's vice president of safety said, in part: "The right skid broke free causing the fuselage to "swing" laterally to the left. Due to the amount of cyclic input applied the fuselage moved left allowing the left skid to make contact with the ground providing a left lateral rolling moment. The main rotor blades made contact with the ground which caused the helicopter to pivot up and around the nose, and come to rest on its right side facing downhill." The transmission was torn loose from its mounts to the fuselage. The tail rotor and engine drive shafts were severed, and the three main rotor blades were destroyed. ## Aircraft - Registration: [N197EH](https://openairdocs.org/deregistered/N197EH-2003-03-06), registration cancelled 2003-03-06, S/N 2983, built 1997 (OpenAirDocs) - Reported make and model: Eurocopter France AS-350-B2 - Registry model: [Eurocopter AS 350 B2](https://openairdocs.org/model/eurocopter-as-350-b2) (registry code 8680950) (OpenAirDocs) - Registry engine: [Turbomeca ARRIEL-1SER](https://openairdocs.org/engine/turbomeca-arriel-1ser) (registry code 60030, turbo-shaft) (OpenAirDocs) - Category: Helicopter - Serial number: 2983 - Airframe hours: 911 - Engines: Turbomeca Arriel 1D1 746 horsepower turbo shaft - Damage: Substantial damage - Flight: Part 135 - Registered owner: Era Aviation, Inc. - Airworthiness certificate: Standard, Normal - Last inspection: AAIP, June 20, 2002, 16 hours before - Departed: Denali Park, AK - Destination: Denali Park, AK - Flight plan: Company VFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 29; injuries: minor; commercial, flight instructor; airplane ratings: single-engine land; instrument ratings: helicopter, airplane; medical: class 1, valid medical--no waivers/lim.; last flight review May 10, 2002; seat: front; toxicology performed; flight hours: 4,039 total, 393 in this make and model, 3,937 as pilot in command, 121 in the last 90 days, 65 in the last 30 days, 3 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 20° at 20 knots, gusting 25 - Visibility: 10 statute miles - Lowest ceiling: 8,000 ft broken - Temperature: 37 °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 20020626016759A](https://openairdocs.org/incident/20020626016759A), Jun 26, 2002: Snias AS350B2, AK, No damage. (-23) While attempting to takeoff up slope from a glacier, the pilot realized too late that the right skid was not breaking free from the icy surface. He… ## Other investigations on N197EH (1) 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. - [NTSB ANC99LA036](https://openairdocs.org/ntsb/ANC99LA036), Mar 17, 1999: Eurocopter AS-350-B2 (N197EH), Girdwood, AK, substantial damage. Probable cause: The pilot's misjudged flare while landing. Factors associated with the accident were whiteout conditions, and snow-covered terrain. ## Docket (2 files) The files NTSB released with the investigation on December 10, 2002, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=55076. 1.1 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 290 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40448237&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Photo 1: Accident site/helicopter on the Yanart Glacier, east of Denali Park. (item 2, .PDF, 776 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40172920&FileExtension=.PDF&FileName=Photo%201%3A%20Accident%20site%2Fhelicopter%20on%20the%20Yanart%20Glacier,%20east%20of%20Denali%20Park.-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.