# NTSB SEA01LA061: Eurocopter AS-350 B2 Ecureuil, N189EH, Mazama, WA, March 11, 2001 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: March 11, 2001, 09:00 local (17:00 UTC) - Place: Mazama, WA - Coordinates: 48.589962, -120.389549 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=48.5900&lon=-120.3895&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Highest injury: Minor injuries - Injuries: 2 minor, 4 uninjured - Status: Completed, report July 30, 2001 - Report: Approved by Office Director - Parties: FAA-FSDO - NTSB case key (mKey): 51900 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA01LA061 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/51900/pdf - Page: https://openairdocs.org/ntsb/SEA01LA061 ## Probable cause The pilot's failure to maintain aircraft control. Snow covered terrain, high and variable wind conditions, and failure of attaining the proper touchdown point were factors. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight collision with terrain/water, landing - aircraft control - not maintained, pilot in command (cause) - terrain condition - snow covered (contributing factor) - weather condition - variable wind (contributing factor) - proper touchdown point - not attained, pilot in command (contributing factor) - weather condition - high wind (contributing factor) - Roll over, landing ## Analysis The pilot approached the remote snow covered mountain site into the wind. During the descent at about 50 feet, the wind increased and shifted. The helicopter began to descend rapidly, and the pilot increased power in an attempt to arrest the rate of descent. Shortly thereafter, the low rotor rpm horn sounded and the helicopter touched down just past the normal landing site with sufficient force and forward speed to prevent him from holding it on the landing site. The pilot applied forward cyclic in an attempt to prevent the helicopter from falling off a 30 foot drop. Due to the low rotor rpm and the inability to maintain altitude, the pilot elected to land the helicopter in a large open snowfield. During the landing, the helicopter settled in the snow and the main rotors contacted the ground. The helicopter subsequently rolled over. The weather at the accident site was reported as high overcast. The wind direction was not indicated, however, the wind velocity was reported at 15-20 knots. No mechanical failures or malfunctions were reported. ## Factual narrative On March 11, 2001, about 0900 Pacific standard time, an Eurocopter AS 350 B2 Ecureuil, N189EH, registered to and operated by Era Aviation Inc. as a 14 CFR Part 135 on demand air taxi service, rolled over after landing on a remote snow covered mountain site on Silverstar Mountain located seven miles west southwest of Mazama, Washington. Visual meteorological conditions prevailed at the time and a company visual flight rules flight plan was in effect. The helicopter was substantially damaged and the commercial pilot and three passengers were not injured. The two remaining passengers received minor injuries. The flight originated from Mazama Heliski Lodge about 15 minutes prior to the accident. In a written statement prepared by Era Aviation's Vice-President - Safety, the purpose of the flight was to drop off skiers at a prepared mountain ridge landing site. The landing site was a small ridge on a large rock outcrop on the north side of the mountain. The area had been leveled and four 4-foot high stakes had been placed in the snow with flags attached to act as wind indicators. The pilot had approached the site into the prevailing winds. During the descent at about 50 feet, the wind increased and shifted to the left side. The helicopter began to descend rapidly, and the pilot increased power in an attempt to arrest the rate of descent. Shortly thereafter the low rotor rpm horn sounded and the helicopter touched down just past the normal landing site with "enough force and forward speed to prevent the pilot from holding it on the intended landing site, so he added forward cyclic in an attempt to prevent it from falling of[f] a 30 foot drop." Due to the low rotor rpm, and the inability to maintain altitude, the pilot elected to land the helicopter in a large open snowfield. During the landing, the helicopter settled into the snow and the main rotors contacted the ground. The helicopter subsequently rolled over. The weather at the accident site was reported as high overcast. The wind direction was not indicated, however, the wind velocity was reported at 15-20 knots. No mechanical failures or malfunctions were reported. ## Aircraft - Registration: N189EH (not matched to a registry record) - Reported make and model: EUROCOPTER AS-350 B2 Ecureuil - Category: Helicopter - Serial number: 2956 - Airframe hours: 1745 - Engines: Turbomeca Arriel/1D1 740 horsepower turbo shaft - Damage: Substantial damage - Flight: Part 135 - Registered owner: Era Aviation, Inc. - Airworthiness certificate: Standard, Normal - Last inspection: AAIP, February 23, 2001, 1,703 hours before - Departed: Mazama, WA - Destination: Mazama, WA - Flight plan: Company VFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 46; injuries: none; commercial, flight instructor; airplane ratings: single-engine land; instrument ratings: airplane, helicopter; medical: class 2, valid medical--no waivers/lim.; last flight review November 30, 2000; seat: right; flight hours: 6,328 total, 1,286 in this make and model, 4,953 as pilot in command, 110 in the last 90 days, 71 in the last 30 days, 4 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 20 knots - Visibility: 10 statute miles - Temperature: 14 °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 20010311005609A](https://openairdocs.org/incident/20010311005609A), Mar 11, 2001: Snias AS350B2, Mazama, WA, No damage. (-23) Pilot attempted landing at heli-ski landing site on mountain face, at approx. 8,300 feet above mean sea level. During landing attempt pilot encountered… 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.