Aircraft Accident/Incident Report

Mayfield, Kentucky 42066
Wednesday, December 4, 1996 16:35 EST

NTSB Narrative Summary Released at Completion of Accident

The pilot stated that the purpose of the flight was to ferry the helicopter. The helicopter had been cruising at 1,200 feet MSL for over an hour, when the nose started to yaw to the right. Unable to control the yaw, the pilot entered an autorotation at about 70 mph to a field. During the forced landing, the helicopter collided with a fence. Examination of the helicopter revealed that the aft pinion nut of the main transmission had disengaged, which allowed the tail rotor splined drive sleeve to disengage from the pinion and tail rotor drive shaft. Investigation did not determined why the aft pinion backed off. The last annual inspection was completed on 6/7/96. The helicopter had accumulated 66 hours of flight time, since the annual inspection.

NTSB Probable Cause Narrative

disengagement of the main transmission aft pinion nut, allowing the tail rotor splined drive sleeve to disengage from the pinion, which resulted in loss of directional control and an emergency (autorotative) landing.

Event Information

Type of Event Accident
Event Date 12/4/1996
Event Day of the Week Wednesday
Time of Event 1635
Event Time Zone Eastern Standard Time
Event City MAYFIELD
Event State KENTUCKY
Event Country --
Zipcode of the event site 42066
Event Date Year 1996
Event Date Month 12
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude
Event Location Longitude
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 Not pertinent
Investigator's weather source Pilot
Time of the weather observation 0
Direction of event from weather observation facility (degrees) 0
Weather Observation Facility ID
Elevation of weather observation facility 0
Distance of event from weather observation facility (units?) 0
Time Zone of the weather observation
Lighting Conditions Day
Lowest Ceiling Height 0
Lowest Non-Ceiling Height 0
Sky/Lowest/Cloud Conditions Clear
Sky Condition for Lowest Ceiling None
Visibility Runway Visual Range (Feet) 0
Visibility Runway Visual Value (Statute Miles) 0
Visibility (Statute Miles) 10
Air Temperature at event time (in degrees celsius) 4
Dew Point at event time (in degress fahrenheit) 2
Wind Direction (degrees magnetic) 0
Variable Wind Indicator Variable
Wind Speed (knots) 0
Wind Velocity Indicator Light and Variable
Wind Gust Indicator Not Gusting
Wind Gust (knots) 0
Altimeter Setting at event time (in. Hg) 30
Density Altitude (feet) --
Intensity of Precipitation Unknown
METAR weather report --
Event Highest Injury None
On Ground, Fatal Injuries 0
On Ground, Minor Injuries 0
On Ground, Serious Injuries 0
Injury Total Fatal --
Injury Total Minor --
Injury Total None 2
Injury Total Serious --
Injury Total All --
Investigating Agency NTSB
NTSB Docket Number (internal use) 1918
NTSB Notification Source --
NTSB Notification Date Dec 4 1996 12:00AM
NTSB Notification Time 2000
Fiche Number and/or location -used to find docket information IMAGE
Date of most recent change to record Jan 10 2001 10:02AM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N1105P
NTSB Number IAD97LA028
Missing Aircraft Indicator N
Federal Aviation Reg. Part Part 91: General Aviation
Type of Flight Plan filed None
Flight plan Was Activated? --
Damage Substantial
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name Hughes
Aircraft Model 269C
Aircraft Series Identifier 269C
Aircraft Serial Number 211028
Certified Max Gross Weight 2050
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 Jun 7 1996 12:00AM
Airframe hours since last inspection 66
Airframe Hours 8640
ELT Installed Unknown
ELT Activated Unknown
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name DR. CHARLES HASSEL
Aircraft Owner Street Address 125 SOUTH STEWART
Aircraft Owner City BREMEN
Aircraft Owner State IN
Aircraft Owner Country
Aircraft Owner Zipcode 46506
Operator is an individual? --
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? No
Certified for Part 133 or 137 Operation Unknown
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) Ferry
Second Pilot on Board No
Departure Point Same as Event No
Departure Airport Code
Departure City HENNING
Departure State TN
Departure Country
Departure Time 1535
Departure Time Zone EST
Destination Same as Local Flt --
Destination Airport Code I21
Destination City INDIANAPOLIS
Destination State IN
Destination Country
Specific Phase of Flight Emergency landing
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Jan 10 2001 12:27PM
User who most recently changed record dbo
Since inspection or accident --
Event Location Runway Number and Location 0
Runway Length --
Runway Width --
Sight Seeing flight No
Air Medical Flight No
Medical Flight --