Aircraft Accident/Incident Report

Coos Bay, Oregon 97420
Thursday, March 10, 2005 12:20 PST

NTSB Narrative Summary Released at Completion of Accident

While in cruise flight, the pilot detected a burning rubber smell and heard "strange loud noises" just as both the engine and rotor rpm began to fluctuate. Soon thereafter, the engine began to lose power, and the pilot elected to make an autorotational landing. He headed for a nearby opening, which turned out to be a cemetery, and as he touched down among the gravestones with zero forward speed, the aircraft rolled over onto its right side. Immediately after it rolled to the side, flames appeared in the cockpit, but the pilot was able to escape out of the left side of the helicopter. A post-accident teardown inspection of the engine and drive assembly revealed that the upper main drive pulley bearing, a double ball bearing assembly, had partially disintegrated, leading to the decoupling of the main rotor shaft drive from the engine output drive shaft. The upper ball bearings were loose in the assembly, and their retaining cage had been destroyed. All of the subject bearings displayed excessive wear, flat spots, and significant thermal damage. Although there was very little grease remaining in the assembly, and the lower drive belt sheave grease passage set screw was found backed half way out, it could not be positively determined whether a lack of lubrication initiated the sequence of events leading to the failure of the bearing assembly, or whether the grease had been consumed by the heat generated by an internal failure resulting from other factors. According to the pilot/builder of the helicopter, he had adhered to the required 25 hour grease service intervals since the aircraft had been built, approximately 115 hours prior to the accident.

NTSB Probable Cause Narrative

The disintegration, for undetermined reasons, of the upper main drive pulley assembly bearing, while in cruise flight, leading to the decoupling of the main rotor drive assembly from the engine drive assembly. Factors include the absence of any suitable forced landing area, leading to a landing between the gravestones of a cemetery.

Event Information

Type of Event Accident
Event Date 3/10/2005
Event Day of the Week Thursday
Time of Event 1220
Event Time Zone Pacific Standard Time
Event City Coos Bay
Event State OREGON
Event Country --
Zipcode of the event site 97420
Event Date Year 2005
Event Date Month 3
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude 432106N
Event Location Longitude 1241058W
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) 17
Dew Point at event time (in degress fahrenheit) --
Wind Direction (degrees magnetic) 330
Variable Wind Indicator Wind direction could be determined
Wind Speed (knots) 7
Wind Velocity Indicator --
Wind Gust Indicator Not Gusting
Wind Gust (knots) --
Altimeter Setting at event time (in. Hg) 30.15
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) 18380
NTSB Notification Source FAA Operations Center
NTSB Notification Date Mar 10 2005 12:00AM
NTSB Notification Time --
Fiche Number and/or location -used to find docket information DMS
Date of most recent change to record Sep 13 2005 12:54PM
User who most recently changed record NTSB\JOHB
Basic weather conditions Visual Meteorological Cond
FAA District Office Portland FSDO

Aircraft Involved

Aircraft #1

Aircraft Registration Number N20539
NTSB Number SEA05LA058
Missing Aircraft Indicator --
Federal Aviation Reg. Part Part 91: General Aviation
Type of Flight Plan filed None
Flight plan Was Activated? No
Damage Destroyed
Aircraft Fire Ground
Aircraft Explosion None
Aircraft Manufacturer's Full Name Rotorway
Aircraft Model Exec 162F
Aircraft Series Identifier --
Aircraft Serial Number 001
Certified Max Gross Weight 1500
Aircraft Category Helicopter
Aircraft Registration Class --
Aircraft is a homebuilt? Yes
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 Conditional
Date of Last Inspection Apr 1 2004 12:00AM
Airframe hours since last inspection 40
Airframe Hours 115
ELT Installed No
ELT Activated No
ELT Aided Location of Event Site No
ELT Type --
Aircraft Owner Name Michael M Garner
Aircraft Owner Street Address --
Aircraft Owner City Myrtle Point
Aircraft Owner State OR
Aircraft Owner Country USA
Aircraft Owner Zipcode 97458
Operator is an individual? No
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? --
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 OTH
Departure City North Bend
Departure State OR
Departure Country USA
Departure Time 1300
Departure Time Zone PST
Destination Same as Local Flt --
Destination Airport Code --
Destination City Norway
Destination State OR
Destination Country USA
Specific Phase of Flight Cruise
Report sent to ICAO? No
Evacuation occurred No
Date of most recent change to record Jun 28 2005 2:15PM
User who most recently changed record STAM
Since inspection or accident Time of Accident
Event Location Runway Number and Location --
Runway Length --
Runway Width --
Sight Seeing flight No
Air Medical Flight No
Medical Flight --