Aircraft Accident/Incident Report

Gustavus, Alaska 99826
Saturday, March 3, 2007 16:10 AST

NTSB Narrative Summary Released at Completion of Accident

The helicopter was being operated as a visual flight rules on-demand passenger flight under Title 14, CFR Part 135. The purpose of the flight was to tranquilize moose for capture and collaring. The company's chief pilot said a moose was shot with a tranquilizer dart from the helicopter, and that the helicopter was used to block the moose from moving into a hazardous area. The pilot of an airplane orbiting above said the moose charged the helicopter, and that as the helicopter attempted to evade the moose, the moose reared, or jumped, contacting the helicopter's tail rotor. The helicopter pilot reported a loss of directional control, and made a hovering autorotation to the ground. The flex coupling between the drive shaft and the tail rotor gearbox failed, and the spinning drive shaft cut the tail boom and separated the tail from the rest of the airframe. According to the chief pilot, the company's practice had been for the helicopter to hover/maneuver about 10 feet above the ground, and no closer to the darted animal than 10 feet horizontally. He said the pilot and scientist aboard felt the distances were appropriate. He said this was the first incident of extreme, erratic, behavior on the part of a darted animal, and that due to this incident, the company has revised its procedure, and now requires the pilot to maintain 30 feet of altitude above the ground and 30 feet horizontally from a darted animal.

NTSB Probable Cause Narrative

The inadequate clearance from a tranquilized moose while hovering in ground effect, and the operator's inadequate procedures for such operations, which resulted in an in-flight collision with the moose. Factors associated with the accident were the moose, a sheared tail rotor drive shaft, and the resultant lack of tail rotor anti-torque control.

Event Information

Type of Event Accident
Event Date 3/3/2007
Event Day of the Week Saturday
Time of Event 1610
Event Time Zone Atlantic Standard Time
Event City Gustavus
Event State ALASKA
Event Country --
Zipcode of the event site 99826
Event Date Year 2007
Event Date Month 3
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude 582536N
Event Location Longitude 1354216W
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 --
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) 10
Air Temperature at event time (in degrees celsius) -8
Dew Point at event time (in degress fahrenheit) -16
Wind Direction (degrees magnetic) --
Variable Wind Indicator --
Wind Speed (knots) --
Wind Velocity Indicator Light and Variable
Wind Gust Indicator Not Gusting
Wind Gust (knots) --
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 2
Injury Total Serious --
Injury Total All --
Investigating Agency NTSB
NTSB Docket Number (internal use) 21730
NTSB Notification Source FAA Anchorage, ROC
NTSB Notification Date Mar 3 2007 12:00AM
NTSB Notification Time --
Fiche Number and/or location -used to find docket information DMS
Date of most recent change to record Jun 27 2007 1:15PM
User who most recently changed record NTSB\lema
Basic weather conditions Visual Meteorological Cond
FAA District Office Juneau FSDO-05

Aircraft Involved

Aircraft #1

Aircraft Registration Number N5134V
NTSB Number ANC07LA022
Missing Aircraft Indicator --
Federal Aviation Reg. Part Part 135: Air Taxi & Commuter
Type of Flight Plan filed Company VFR
Flight plan Was Activated? --
Damage Substantial
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name Hughes
Aircraft Model 369D
Aircraft Series Identifier --
Aircraft Serial Number 1103D
Certified Max Gross Weight 3000
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 100 Hour
Date of Last Inspection Oct 1 2006 12:00AM
Airframe hours since last inspection --
Airframe Hours 9041
ELT Installed Yes
ELT Activated No
ELT Aided Location of Event Site No
ELT Type --
Aircraft Owner Name Temsco Helicopter Inc.
Aircraft Owner Street Address --
Aircraft Owner City Ketchikan
Aircraft Owner State AK
Aircraft Owner Country USA
Aircraft Owner Zipcode --
Operator is an individual? No
Operator Name TEMSCO HELICOPTERS INC
Operator Same as Owner? Yes
Operator Is Doing Business As --
Operator Address Same as Owner? Yes
Operator Street Address --
Operator City Ketchikan
Operator State AK
Operator Country USA
Operator Zip code 99901
Operator Code HXSD
Owner has at least one certificate --
Other Operator of large aircraft? --
Certified for Part 133 or 137 Operation External Load
Operator Certificate Number --
Indicates whether an air carrier operation was scheduled or not Non-scheduled
Indicates Domestic or International Flight Domestic
Operator carrying Pax/Cargo/Mail Passenger Only
Type of Flying (Per_Bus / Primary) --
Second Pilot on Board No
Departure Point Same as Event No
Departure Airport Code PAGS
Departure City Gustavus
Departure State AK
Departure Country USA
Departure Time 1230
Departure Time Zone AST
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 Hover - in ground effect
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Jun 13 2007 11:49PM
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 --