Individually Owned: 150,657
Corporate Owned: 137,281
Johnson County Airport
Aircraft Accident/Incident Report
Buffalo, Wyoming 82834
Tuesady, June 24, 2008 13:45 MDT
NTSB Narrative Summary Released at Completion of Accident
The helicopter pilot was picking up a biologist who was conducting land surveys. Prior to landing he circled the landing zone to observe the wind conditions. During the landing approach he transitioned out of effective translational lift earlier than expected, and attributed this to a reduced headwind caused by the enclosed terrain. During departure and acceleration to effective translational lift speed, the rotor speed began to decay. The ground speed was faster than he anticipated so he lowered the collective, and added forward cyclic, but could not maintain enough rotor speed for sustained flight. The pilot elected to land the helicopter ahead on a 30-degree uphill slope. After landing, the helicopter rolled back and the tail rotor made contact with the ground causing substantial damage to the tail rotor drive system. After the accident the pilot noted that the winds had shifted 180 degrees from his initial pre-accident observation.
NTSB Probable Cause Narrative
The pilot's attempted downwind takeoff that resulted in an aborted takeoff. Contributing to the accident was the unsuitable terrain.
Event Information
| Type of Event | Accident |
| Event Date | 6/24/2008 |
| Event Day of the Week | Tuesday |
| Time of Event | 1345 |
| Event Time Zone | Mountain Daylight Time |
| Event City | Buffalo |
| Event State | WYOMING |
| Event Country | -- |
| Zipcode of the event site | 82834 |
| Event Date Year | 2008 |
| Event Date Month | 6 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 441921N |
| Event Location Longitude | 1061540W |
| Event Location Airport | Johnson County Airport |
| Event Location Nearest Airport ID | KBYG |
| Indicates whether the acc/inc occurred off or on an airport | Off Airport/Airstrip |
| Distance from airport in statute miles | 24 |
| Degrees magnetic from airport | -- |
| Airport Elevation | 4968 |
| Weather Briefing Completeness | -- |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 1353 Mountain Daylight Time |
| Direction of event from weather observation facility (degrees) | 270 |
| Weather Observation Facility ID | KBYG |
| Elevation of weather observation facility | 4968 |
| Distance of event from weather observation facility (units?) | 24 |
| Time Zone of the weather observation | MDT |
| 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) | 28 |
| Dew Point at event time (in degress fahrenheit) | 12 |
| Wind Direction (degrees magnetic) | 10 |
| Variable Wind Indicator | Wind direction could be determined |
| Wind Speed (knots) | 13 |
| Wind Velocity Indicator | -- |
| Wind Gust Indicator | Gusting |
| Wind Gust (knots) | 19 |
| Altimeter Setting at event time (in. Hg) | 30.01 |
| 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) | 24620 |
| NTSB Notification Source | FAA ROC |
| NTSB Notification Date | Jun 24 2008 12:00AM |
| NTSB Notification Time | -- |
| Fiche Number and/or location -used to find docket information | -- |
| Date of most recent change to record | Jan 26 2009 9:58AM |
| User who most recently changed record | grol |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | Casper FSDO |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N432MS |
| NTSB Number | LAX08LA196 |
| Missing Aircraft Indicator | -- |
| Federal Aviation Reg. Part | Part 135: Air Taxi & Commuter |
| Type of Flight Plan filed | None |
| Flight plan Was Activated? | No |
| Damage | Substantial |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | SCHWEIZER |
| Aircraft Model | 269C |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | S1437 |
| Certified Max Gross Weight | 2050 |
| 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 | 3 |
| Number of Engines | 1 |
| Fixed gear or retractable gear | Fixed |
| Aircraft, Type of Last Inspection | 100 Hour |
| Date of Last Inspection | Jun 11 2008 12:00AM |
| Airframe hours since last inspection | 42 |
| Airframe Hours | 3293 |
| ELT Installed | Yes |
| ELT Activated | No |
| ELT Aided Location of Event Site | No |
| ELT Type | Unknown |
| Aircraft Owner Name | Northern Skies Aviation Inc. |
| Aircraft Owner Street Address | P.O. Box 936 |
| Aircraft Owner City | Laurel |
| Aircraft Owner State | MT |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 59044 |
| Operator is an individual? | No |
| Operator Name | Northern Skies Aviation Inc. |
| Operator Same as Owner? | Yes |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | Yes |
| Operator Street Address | P.O. Box 936 |
| Operator City | Laurel |
| Operator State | MT |
| Operator Country | USA |
| Operator Zip code | 59044 |
| Operator Code | N3SA |
| Owner has at least one certificate | Yes - certificate holder |
| Other Operator of large aircraft? | No |
| 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 | -- |
| Departure City | Buffalo |
| Departure State | WY |
| Departure Country | USA |
| Departure Time | 1340 |
| Departure Time Zone | MDT |
| Destination Same as Local Flt | dest & departure same, accident can occur anywhere |
| Destination Airport Code | -- |
| Destination City | Buffalo |
| Destination State | WY |
| Destination Country | USA |
| Specific Phase of Flight | Takeoff |
| Report sent to ICAO? | -- |
| Evacuation occurred | -- |
| Date of most recent change to record | Dec 9 2011 11:23AM |
| User who most recently changed record | broda |
| Since inspection or accident | Time of Accident |
| Event Location Runway Number and Location | N/A |
| Runway Length | -- |
| Runway Width | -- |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |