Off Airport
Aircraft Accident/Incident Report

Sheep Mountain, Montana 59739
Monday, July 16, 2007 8:30 MDT

NTSB Narrative Summary Released at Completion of Accident

The helicopter was transporting supplies with a cargo net from one mountain site to another. The sling loads consisted of steel angle iron, which was bagged and secured with velcro, and then placed into the cargo net. After delivering the fourth load, the pilot lifted off with only an empty bag inside the net. The Bell 206B rotorcraft flight manual, in the supplement for external loading, states, "Control movements should be made smoothly and kept to a minimum to prevent oscillation of sling load." According to a witness, as the helicopter departed, the net "floated very close to the propeller [tail rotor], then floated back down." The net, which was attached directly to the helicopter cargo hook without the use of a long line, swung back up again and impacted the tail rotor, cutting the cargo net and releasing the bag. The pilot heard noise and "thumping" sounds, accompanied by vibrations and yawing, and realized that he had a tail rotor strike. The pilot entered an autorotation at "25 miles per hour and 200 feet" above a timbered slope. The pilot selected a small, sloped, clearing as a landing zone, and upon touchdown, the helicopter rolled over, coming to rest on it's right side.

NTSB Probable Cause Narrative

The external load net, attached directly to the cargo hook without the use of a long line, oscillated and made contact with the tail rotor system while maneuvering.

Event Information

Type of Event Accident
Event Date 7/16/2007
Event Day of the Week Monday
Time of Event 830
Event Time Zone Mountain Daylight Time
Event City Sheep Mountain
Event State MONTANA
Event Country --
Zipcode of the event site 59739
Event Date Year 2007
Event Date Month 7
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude 443327N
Event Location Longitude 1114630W
Event Location Airport Off Airport
Event Location Nearest Airport ID NONE
Indicates whether the acc/inc occurred off or on an airport Off Airport/Airstrip
Distance from airport in statute miles 0
Degrees magnetic from airport --
Airport Elevation --
Weather Briefing Completeness --
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) 30
Air Temperature at event time (in degrees celsius) 18
Dew Point at event time (in degress fahrenheit) --
Wind Direction (degrees magnetic) --
Variable Wind Indicator --
Wind Speed (knots) --
Wind Velocity Indicator Calm
Wind Gust Indicator Unknown
Wind Gust (knots) --
Altimeter Setting at event time (in. Hg) 29.92
Density Altitude (feet) --
Intensity of Precipitation --
METAR weather report --
Event Highest Injury Minor
On Ground, Fatal Injuries --
On Ground, Minor Injuries --
On Ground, Serious Injuries --
Injury Total Fatal --
Injury Total Minor 1
Injury Total None --
Injury Total Serious --
Injury Total All 1
Investigating Agency NTSB
NTSB Docket Number (internal use) 22499
NTSB Notification Source SO - Beaver Head County
NTSB Notification Date --
NTSB Notification Time --
Fiche Number and/or location -used to find docket information DMS
Date of most recent change to record Nov 29 2007 8:02AM
User who most recently changed record NTSB\johb
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N164JS
NTSB Number SEA07CA200
Missing Aircraft Indicator --
Federal Aviation Reg. Part Part 133: Rotorcraft Ext. Load
Type of Flight Plan filed None
Flight plan Was Activated? --
Damage Substantial
Aircraft Fire Ground
Aircraft Explosion None
Aircraft Manufacturer's Full Name Bell
Aircraft Model 206B II
Aircraft Series Identifier --
Aircraft Serial Number 955
Certified Max Gross Weight 3350
Aircraft Category Helicopter
Aircraft Registration Class --
Aircraft is a homebuilt? No
Flight Crew Seats --
Cabin Crew Seats --
Passenger Seats --
Total number of seats on the aircraft 5
Number of Engines 1
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection --
Date of Last Inspection Jun 1 2007 12:00AM
Airframe hours since last inspection --
Airframe Hours 5043
ELT Installed Yes
ELT Activated Yes
ELT Aided Location of Event Site --
ELT Type --
Aircraft Owner Name J.R. Simplot Company
Aircraft Owner Street Address --
Aircraft Owner City Boise
Aircraft Owner State ID
Aircraft Owner Country USA
Aircraft Owner Zipcode 83705
Operator is an individual? No
Operator Name Ronald L. Young
Operator Same as Owner? No
Operator Is Doing Business As --
Operator Address Same as Owner? No
Operator Street Address --
Operator City Eagle
Operator State ID
Operator Country USA
Operator Zip code 83616
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) External Load
Second Pilot on Board No
Departure Point Same as Event No
Departure Airport Code --
Departure City Mtn Drop Site
Departure State MT
Departure Country USA
Departure Time 820
Departure Time Zone MDT
Destination Same as Local Flt --
Destination Airport Code --
Destination City Mtn Drop Site
Destination State MT
Destination Country USA
Specific Phase of Flight --
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Aug 24 2007 7:28PM
User who most recently changed record STAM
Since inspection or accident Time of Accident
Event Location Runway Number and Location NA
Runway Length --
Runway Width --
Sight Seeing flight No
Air Medical Flight No
Medical Flight --