N/A Airport
Aircraft Accident/Incident Report

Nederland, Colorado 80466
Saturday, June 8, 2002 10:30 MDT

NTSB Narrative Summary Released at Completion of Accident

Prior to the flight in mountainous terrain, the pilot obtained a weather forecast that called for winds from the southwest at 30 mph, with gusts up to 40 mph. The flight departed and was in cruise flight at 9,000 feet (700 feet agl) with a 20-25 knot headwind and experiencing light turbulence, when the flight encountered "severe turbulence." The pilot stated that the helicopter went "up and down violently for a period of 2-3 seconds." The tailrotor drive shaft was severed by the main rotor blades, and the helicopter then experienced "a right yaw that full application of left pedal would not correct." The pilot stated that during the event the engine and rotor rpm increased past their upper limits. He was able to bring the engine and rotor rpm within limits and regained control of the helicopter. Subsequently, the pilot performed an autorotation to sloping terrain without further incident. According to a witness, who was fishing on a lake 4 miles from the accident site, he observed water spouts between 2 and 8 feet tall and high swirling winds near the time of the accident.

NTSB Probable Cause Narrative

the pilot's inadvertent in-flight encounter with severe turbulence, which resulted in main rotor-tailboom contact and the separation of the tailrotor drive shaft.

Event Information

Type of Event Accident
Event Date 6/8/2002
Event Day of the Week Saturday
Time of Event 1030
Event Time Zone Mountain Daylight Time
Event City Nederland
Event State COLORADO
Event Country --
Zipcode of the event site 80466
Event Date Year 2002
Event Date Month 6
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude 404004N
Event Location Longitude 1060309W
Event Location Airport N/A
Event Location Nearest Airport ID --
Indicates whether the acc/inc occurred off or on an airport Off Airport/Airstrip
Distance from airport in statute miles --
Degrees magnetic from airport --
Airport Elevation --
Weather Briefing Completeness Not pertinent
Investigator's weather source Pilot
Time of the weather observation
Direction of event from weather observation facility (degrees) --
Weather Observation Facility ID --
Elevation of weather observation facility --
Distance of event from weather observation facility (units?) --
Time Zone of the weather observation --
Lighting Conditions Day
Lowest Ceiling Height --
Lowest Non-Ceiling Height --
Sky/Lowest/Cloud Conditions Clear
Sky Condition for Lowest Ceiling None
Visibility Runway Visual Range (Feet) --
Visibility Runway Visual Value (Statute Miles) --
Visibility (Statute Miles) --
Air Temperature at event time (in degrees celsius) 18
Dew Point at event time (in degress fahrenheit) --
Wind Direction (degrees magnetic) 200
Variable Wind Indicator Wind direction could be determined
Wind Speed (knots) 20
Wind Velocity Indicator --
Wind Gust Indicator Gusting
Wind Gust (knots) 25
Altimeter Setting at event time (in. Hg) --
Density Altitude (feet) --
Intensity of Precipitation --
METAR weather report --
Event Highest Injury None
On Ground, Fatal Injuries --
On Ground, Minor Injuries --
On Ground, Serious Injuries --
Injury Total Fatal --
Injury Total Minor --
Injury Total None 1
Injury Total Serious --
Injury Total All --
Investigating Agency NTSB
NTSB Docket Number (internal use) 12801
NTSB Notification Source FAA
NTSB Notification Date Jun 8 2002 12:00AM
NTSB Notification Time 1200
Fiche Number and/or location -used to find docket information DMS
Date of most recent change to record Apr 1 2003 4:20PM
User who most recently changed record NTSB\MONR
Basic weather conditions Visual Meteorological Cond
FAA District Office Denver, Colorado

Aircraft Involved

Aircraft #1

Aircraft Registration Number N999DW
NTSB Number FTW02LA177
Missing Aircraft Indicator --
Federal Aviation Reg. Part Part 91: General Aviation
Type of Flight Plan filed None
Flight plan Was Activated? No
Damage Substantial
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name Bell
Aircraft Model 47G-3B-1
Aircraft Series Identifier --
Aircraft Serial Number 6604
Certified Max Gross Weight 2950
Aircraft Category Helicopter
Aircraft Registration Class U.S. Registered/U.S. Soil
Aircraft is a homebuilt? No
Flight Crew Seats --
Cabin Crew Seats --
Passenger Seats --
Total number of seats on the aircraft 3
Number of Engines 1
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection Annual
Date of Last Inspection Jul 10 2001 12:00AM
Airframe hours since last inspection 75.6
Airframe Hours 4123
ELT Installed Yes
ELT Activated No
ELT Aided Location of Event Site No
ELT Type --
Aircraft Owner Name Bernard P. Gateau
Aircraft Owner Street Address 7500 Magnolia Drive
Aircraft Owner City Nederland
Aircraft Owner State CO
Aircraft Owner Country USA
Aircraft Owner Zipcode 80466
Operator is an individual? No
Operator Name --
Operator Same as Owner? Yes
Operator Is Doing Business As --
Operator Address Same as Owner? Yes
Operator Street Address --
Operator City --
Operator State --
Operator Country --
Operator Zip code --
Operator Code --
Owner has at least one certificate None
Other Operator of large aircraft? --
Certified for Part 133 or 137 Operation --
Operator Certificate Number --
Indicates whether an air carrier operation was scheduled or not --
Indicates Domestic or International Flight --
Operator carrying Pax/Cargo/Mail --
Type of Flying (Per_Bus / Primary) Personal
Second Pilot on Board --
Departure Point Same as Event No
Departure Airport Code NONE
Departure City Nederland
Departure State CO
Departure Country USA
Departure Time 900
Departure Time Zone MDT
Destination Same as Local Flt dest & departure same, accident can occur anywhere
Destination Airport Code --
Destination City --
Destination State --
Destination Country --
Specific Phase of Flight Cruise
Report sent to ICAO? No
Evacuation occurred Yes
Date of most recent change to record Dec 4 2002 4:35PM
User who most recently changed record CASH
Since inspection or accident Time of Accident
Event Location Runway Number and Location --
Runway Length --
Runway Width --
Sight Seeing flight No
Air Medical Flight No
Medical Flight --