# NTSB LAX97LA110: Bell 206B, N42SS, Mountain Spring, NV, February 24, 1997 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Limited investigation · Final report - Date: February 24, 1997, 13:15 local (21:15 UTC) - Place: Mountain Spring, NV - Coordinates: 36.170356, -115.120941 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=36.1704&lon=-115.1209&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Highest injury: Serious injuries - Injuries: 1 serious, 2 minor - Status: Completed, report October 14, 1997 - Report: Approved by Office Director - NTSB case key (mKey): 29730 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX97LA110 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/29730/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=29730 - Page: https://openairdocs.org/ntsb/LAX97LA110 ## Probable cause the pilot's poor weather evaluation and the decision to continue to attempt to land during forecast adverse weather conditions. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight encounter with weather, approach - vfr pattern - final approach - weather condition - turbulence,terrain induced - weather condition - high density altitude - weather evaluation - poor, pilot in command (cause) - flight into known adverse weather - performed, pilot in command (cause) - Loss of control - in flight, landing - aborted - weather condition - downdraft - aircraft performance,landing capability - exceeded - In flight collision with terrain/water, descent - uncontrolled - terrain condition - mountainous/hilly - altitude/clearance - not maintained, pilot in command ## Analysis The pilot encountered turbulent wind conditions on short final approach to the mountain helipad. He aborted his first two approaches and attempted a third. During the third approach he encountered the turbulent conditions again. He attempted to maneuver the helicopter by turning downslope and avoid the upsloping terrain. While in the turn the helicopter struck high vegetation and then the ground. The pilot reported that he checked weather by listening to the Reno Flight Service Station recorded weather. A SIGMENT was in effect at the time and was forecasting severe turbulence. The SIGMENT stated, 'Strong updrafts and down drafts over mountains and also low level wind shear expected.' The elevation of the mountain helipad was 8,514 feet msl. ## Factual narrative On February 24, 1997, at 1315 hours Pacific standard time, a Bell 206B helicopter, N42SS, collided with high vegetation while landing on a remote helipad on Mount Potosi, about 4 miles south of Mountain Springs, Nevada. The helicopter was destroyed by postimpact fire. The airline transport pilot and one passenger received minor injuries, and one passenger received serious injuries. The helicopter was operated by Sundance Helicopters, Inc., Las Vegas, Nevada, as an on-demand nonscheduled domestic passenger flight under 14 CFR Part 135 when the accident occurred. The flight originated in Las Vegas at 1240. Visual meteorological conditions prevailed at the time and a company VFR flight plan was filed. The pilot indicated he encountered an updraft on short final approach to the mountain helipad, which resulted in aborting the first two approaches. On the third approach, the pilot encountered updrafts again and attempted to maneuver the helicopter by turning downslope and avoid the upsloping terrain. While in the turn, the pilot encountered a downdraft and the helicopter struck high vegetation and the ground. The helicopter rolled downslope and caught fire after it came to rest. The occupants were able to egress the helicopter before receiving any burn injuries. The pilot reported that he checked weather by listening to the Reno Flight Service Station recorded weather. SIGMENT Yankee was in effect and was forecasting severe turbulence below 15,000 feet msl in the area due to a steady northeasterly flow. The SIGMENT stated, "Strong updrafts and down drafts over mountains and also low level wind shear expected." Mount Potosi, elevation 8,514 feet msl, is located about 20 miles west of Las Vegas. The Las Vegas scheduled record observation at 1256 hours was reporting winds from 020 degrees at 19 knots. ## Aircraft - Registration: [N42SS](https://openairdocs.org/deregistered/N42SS-2000-05-01), registration cancelled 2000-05-01, S/N 3345 (OpenAirDocs) - Reported make and model: Bell 206B - Registry model: [Bell 206B](https://openairdocs.org/model/bell-206b) (registry code 1181511) (OpenAirDocs) - Category: Helicopter - Serial number: 3345 - Airframe hours: 6597 - Engines: Allison 250-C20B 425 horsepower turbo shaft - Damage: Destroyed - Fire: On-Ground - Flight: Part 135 - Registered owner: Sundance Helicopters, Inc. - Airworthiness certificate: Standard, Normal - Last inspection: Annual, February 21, 1997, 20 hours before - Departed: LAS, LAS VEGAS, NV - Flight plan: Company VFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 49; airline transport, commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; seat: right; flight hours: 10,994 total, 4,905 in this make and model, 10,370 as pilot in command, 177 in the last 90 days, 70 in the last 30 days, 2 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 20° at 19 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 55 °F, dew point 10 °F - Altimeter: 30.00 inHg - Observed at: LAS, 19 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 19970224001829A](https://openairdocs.org/incident/19970224001829A), Feb 24, 1997: Bell 206B, Mt Potosi, NV, Destroyed. Helicopter landed hard after encountering heavy downdraft, rolled and destroyed by fire. ## Docket (3 files) The files NTSB released with the investigation on August 13, 1997, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=29730. 614 KB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1/2 (item 1, .PDF, 414 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40414571&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1%2F2-Redacted.PDF - Supplement S (item 2, .PDF, 53 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40071269&FileExtension=.PDF&FileName=Supplement%20S-Master.PDF - Passenger Statement (item 3, .PDF, 146 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40414572&FileExtension=.PDF&FileName=Passenger%20Statement-Redacted.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.