# NTSB DEN01LA060: Bell 407, N9HE, Jackson, WY, March 2, 2001 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: March 2, 2001, 12:00 local (19:00 UTC) - Place: Jackson, WY - Coordinates: 43.469074, -110.759223 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=43.4691&lon=-110.7592&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report July 30, 2001 - Report: Approved by Office Director - Parties: FAA Flight Standards Field Office - NTSB case key (mKey): 51845 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN01LA060 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/51845/pdf - Page: https://openairdocs.org/ntsb/DEN01LA060 ## Probable cause The pilot's failure to maintain adequate lateral and vertical clearance during landing. Factors were the clouds and snow-covered high terrain. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight collision with terrain/water, landing - flare/touchdown - altitude/clearance - inadequate, pilot in command (cause) - terrain condition - high terrain (contributing factor) - terrain condition - snow covered (contributing factor) - weather condition - clouds (contributing factor) ## Analysis The pilot of the helicopter was looking for a group of people to be picked up at a designated point. Flying over the location, he realized that they had not yet arrived, so he decided to land at an alternate location and await their arrival. He had landed at the alternate location previously but not on the day of the accident. He said the visibility was good, but there were no shadows due to the overcast. The approach was normal, and the pilot used a small pine tree to the right front quarter of the helicopter as a reference point. As the helicopter touched down, the pilot heard a loud noise and the helicopter yawed. Believing there had been a mechanical failure, the pilot lowered the collective control and closed the throttle. Postaccident inspection revealed there had not been a mechanical failure. Rather, the pilot had not seen the snow covered slope to the left front quarter of the helicopter. The main rotor blades struck the surface of the ground and the helicopter settled into deep snow. The transmission separated from its mounts, the main rotor blades were destroyed, and the tail boom was severed. ## Factual narrative On March 2, 2001, at approximately 1200 mountain standard time, N9HE, a Bell 407, owned and operated by Helicopter Express, Inc., of Lawrenceville, Georgia, was substantially damaged when it collided with terrain while landing about 22 miles southwest of Jackson, Wyoming. The commercial certificated pilot, the sole occupant aboard, was not injured. Visual meteorological conditions prevailed, and no flight plan had been filed for the positioning flight being conducted under Title 14 CFR Part 91. The flight originated approximately 1020. According to the pilot's accident report, the pilot was looking for a group of people to be picked up at a designated point. Flying over the location, he realized that they had not yet arrived, so he decided to land at an alternate location and await their arrival. He had landed at the alternate location previously but not on the day of the accident. He said the visibility was good, but there were no shadows due to the overcast. The approach was normal, and the pilot used a small pine tree to the right front quarter of the helicopter as a reference point. As the helicopter touched down, the pilot heard a loud noise and the helicopter yawed. Believing there had been a mechanical failure, the pilot lowered the collective control and closed the throttle. Postaccident inspection revealed that the main rotor blades struck a snow covered slope to the left front quarter of the helicopter, and the helicopter settled into deep snow. The transmission separated from its mounts, the main rotor blades were destroyed, and the tail boom was severed. ## Aircraft - Registration: [N9HE](https://openairdocs.org/deregistered/N9HE-2015-05-21), registration cancelled 2015-05-21, S/N 53073, built 1996 (OpenAirDocs) - Reported make and model: Bell 407 - Registry model: [Bell 407](https://openairdocs.org/model/bell-407) (registry code 1182206) (OpenAirDocs) - Registry engine: [Allison 250-C47 series](https://openairdocs.org/engine/allison-250-c47-series) (registry code 03029, turbo-shaft) (OpenAirDocs) - Category: Helicopter - Serial number: 53073 - Airframe hours: 1950 - Engines: Rolls-Royce Allison C250-C47B 650 horsepower turbo shaft - Damage: Substantial damage - Flight: Positioning, Part 91 - Registered owner: Helicopter Express, Inc. - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, February 19, 2001, 17 hours before - Departed: NONE, Jackson, WY - Flight plan: Company VFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 51; injuries: none; commercial; airplane ratings: single-engine land; instrument ratings: helicopter; medical: class 2, valid medical--w/ waivers/lim; last flight review October 11, 2000; seat: right; flight hours: 22,300 total, 140 in this make and model, 22,200 as pilot in command, 90 in the last 90 days, 38 in the last 30 days, 4 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 0° at 0 knots - Visibility: 8 statute miles - Lowest ceiling: none - Temperature: 16 °F, dew point 5 °F - Altimeter: 29.77 inHg - Observed at: JAC, 10 nm away ## 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 20010302004169A](https://openairdocs.org/incident/20010302004169A), Mar 2, 2001: Bell 407, Jackson, WY, No damage. (-23) When the helicopter touched down, the surface of the snow collapsed and the helicopter rolled over. Substantial damage, no injury. 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.