Aircraft Accident/Incident Report

Vinson, Oklahoma 73554
Saturday, October 12, 2002 9:45 CDT

NTSB Narrative Summary Released at Completion of Accident

After the helicopter leveled off at 2,500 feet, scattered clouds began moving in. The pilot climbed to 4,500 feet where clouds were now above and below him, preventing the pilot from locating his next checkpoint until there were breaks in the clouds. Approximately 56 miles into the flight and with the clouds thinning, the helicopter broke into a right turn. After turning back on course the helicopter began gaining altitude, then nosed over quickly, dropping approximately 1,000 feet. After leveling off back on course, the helicopter began gaining altitude again to 5,000 feet and began a smooth left-hand descending turn into a canyon. All attempted control inputs by the pilot were unresponsive. The helicopter was now traveling at a high rate of speed through the canyon, eventually coming to a quick stop to the right on a hill at the end of the canyon. As rotor rpm bled off the pilot attempted another control input by applying aft cyclic and left rudder pedal; however, the helicopter would not respond. The helicopter impacted terrain in a rapid spin to the left, coming to rest on its left side. Post-accident examination of the helicopter's flight controls revealed no anomalies which would have prevented normal operations. Approximately two hours prior to departure, a warm front was moving into the area of intended flight. At the time of the accident, weather observation facilities in the region reported winds gusting up to 31 knots with multilayered clouds.

NTSB Probable Cause Narrative

The pilot's inadvertent flight into adverse weather conditions during cruise resulting in his failure to maintain control of the helicopter, and his failure to maintain rotor rpm. Contributing factors relating to the accident included the frontal activity associated with the adverse weather condition and the variable wind.

Event Information

Type of Event Accident
Event Date 10/12/2002
Event Day of the Week Saturday
Time of Event 945
Event Time Zone Central Daylight Time
Event City Vinson
Event State OKLAHOMA
Event Country --
Zipcode of the event site 73554
Event Date Year 2002
Event Date Month 10
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude 345854N
Event Location Longitude 0995212W
Event Location Airport --
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 Partial - limited by pilot
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 200
Sky/Lowest/Cloud Conditions Scattered
Sky Condition for Lowest Ceiling None
Visibility Runway Visual Range (Feet) --
Visibility Runway Visual Value (Statute Miles) --
Visibility (Statute Miles) 10
Air Temperature at event time (in degrees celsius) 14
Dew Point at event time (in degress fahrenheit) --
Wind Direction (degrees magnetic) 260
Variable Wind Indicator Wind direction could be determined
Wind Speed (knots) 10
Wind Velocity Indicator --
Wind Gust Indicator Not Gusting
Wind Gust (knots) --
Altimeter Setting at event time (in. Hg) 29.96
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 2
Injury Total Serious --
Injury Total All --
Investigating Agency NTSB
NTSB Docket Number (internal use) 14433
NTSB Notification Source FAA
NTSB Notification Date Oct 12 2002 12:00AM
NTSB Notification Time 1500
Fiche Number and/or location -used to find docket information DMS
Date of most recent change to record Nov 25 2003 11:36AM
User who most recently changed record NTSB\MONR
Basic weather conditions Visual Meteorological Cond
FAA District Office Oklahoma City, Oklahoma

Aircraft Involved

Aircraft #1

Aircraft Registration Number N9008H
NTSB Number FTW03LA011
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 Brantly Helicopter
Aircraft Model B-2B
Aircraft Series Identifier --
Aircraft Serial Number 2017
Certified Max Gross Weight 1670
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 2
Number of Engines 1
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection Annual
Date of Last Inspection Apr 23 2002 12:00AM
Airframe hours since last inspection 4.2
Airframe Hours 48.9
ELT Installed No
ELT Activated No
ELT Aided Location of Event Site No
ELT Type --
Aircraft Owner Name Brantly International Inc.
Aircraft Owner Street Address 12399 Airport Drive
Aircraft Owner City Vernon
Aircraft Owner State TX
Aircraft Owner Country USA
Aircraft Owner Zipcode 76384
Operator is an individual? No
Operator Name --
Operator Same as Owner? Yes
Operator Is Doing Business As --
Operator Address Same as Owner? No
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 No
Departure Point Same as Event No
Departure Airport Code F05
Departure City Vernon
Departure State TX
Departure Country USA
Departure Time 850
Departure Time Zone CDT
Destination Same as Local Flt --
Destination Airport Code HHF
Destination City Canadian
Destination State TX
Destination Country USA
Specific Phase of Flight Descent - uncontrolled
Report sent to ICAO? No
Evacuation occurred No
Date of most recent change to record Jul 31 2003 6:01PM
User who most recently changed record STAM
Since inspection or accident --
Event Location Runway Number and Location --
Runway Length --
Runway Width --
Sight Seeing flight No
Air Medical Flight No
Medical Flight --