Individually Owned: 150,657
Corporate Owned: 137,281
Henry County Airport
Aircraft Accident/Incident Report
Napoleon, Ohio 43545
Saturday, February 3, 2001 11:30 EST
NTSB Narrative Summary Released at Completion of Accident
The helicopter developed a vibration, and the pilot elected to return to the departure airport. On final approach to landing, approximately 10 feet above the ground, the main rotor mast fractured, and the main rotor system departed the helicopter. The pilot and two passengers were not injured. Examination of the fracture surfaces by a Safety Board metallurgist revealed the mast failed in fatigue in the area of the fillet radius. Microscopic examination revealed that a portion of the fatigue region had been painted over with paint that matched the exterior of the mast. The mast installed in the accident helicopter had a narrower fillet radius than masts subsequently produced by the manufacturer. An FAA Airworthiness Directive (AD) that required inspecting and strengthening of the fillet radius affected the narrower masts. As a result of this investigation, the FAA amended the AD to immediately retire some transmission/mast combinations, and to ultimately remove all of the narrower masts from service.
NTSB Probable Cause Narrative
The fatigue failure in the fillet radius of the mast, which resulted in the separation of the main rotor system.
Event Information
| Type of Event | Accident |
| Event Date | 2/3/2001 |
| Event Day of the Week | Saturday |
| Time of Event | 1130 |
| Event Time Zone | Eastern Standard Time |
| Event City | Napoleon |
| Event State | OHIO |
| Event Country | -- |
| Zipcode of the event site | 43545 |
| Event Date Year | 2001 |
| Event Date Month | 2 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 412227N |
| Event Location Longitude | 0840404W |
| Event Location Airport | Henry County |
| Event Location Nearest Airport ID | 7W5 |
| Indicates whether the acc/inc occurred off or on an airport | On Airport |
| Distance from airport in statute miles | -- |
| Degrees magnetic from airport | -- |
| Airport Elevation | 683 |
| Weather Briefing Completeness | Not pertinent |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 1152 Eastern Standard Time |
| Direction of event from weather observation facility (degrees) | 30 |
| Weather Observation Facility ID | TOL |
| Elevation of weather observation facility | 684 |
| Distance of event from weather observation facility (units?) | 17 |
| Time Zone of the weather observation | EST |
| Lighting Conditions | Day |
| Lowest Ceiling Height | 4800 |
| Lowest Non-Ceiling Height | -- |
| Sky/Lowest/Cloud Conditions | -- |
| Sky Condition for Lowest Ceiling | Broken |
| Visibility Runway Visual Range (Feet) | -- |
| Visibility Runway Visual Value (Statute Miles) | -- |
| Visibility (Statute Miles) | 10 |
| Air Temperature at event time (in degrees celsius) | -7 |
| Dew Point at event time (in degress fahrenheit) | -12 |
| Wind Direction (degrees magnetic) | 180 |
| Variable Wind Indicator | Wind direction could be determined |
| Wind Speed (knots) | 11 |
| Wind Velocity Indicator | -- |
| Wind Gust Indicator | Not Gusting |
| Wind Gust (knots) | -- |
| Altimeter Setting at event time (in. Hg) | 30.27 |
| Density Altitude (feet) | -2307 |
| Intensity of Precipitation | -- |
| METAR weather report | KTOL 031552Z 18011KT 10SM BKN048 OVC065 M07/M12 A3 |
| 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 | 3 |
| Injury Total Serious | -- |
| Injury Total All | -- |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 13356 |
| NTSB Notification Source | Cleveland FSDO |
| NTSB Notification Date | Feb 4 2001 12:00AM |
| NTSB Notification Time | 1500 |
| Fiche Number and/or location -used to find docket information | DMS |
| Date of most recent change to record | May 13 2003 12:26PM |
| User who most recently changed record | NTSB\MONR |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | FSDO #25 Cleveland, Ohio |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N98PM |
| NTSB Number | IAD01LA031 |
| Missing Aircraft Indicator | -- |
| Federal Aviation Reg. Part | Part 91: General Aviation |
| Type of Flight Plan filed | None |
| Flight plan Was Activated? | No |
| Damage | Substantial |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | Enstrom |
| Aircraft Model | F28A |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | 200 |
| Certified Max Gross Weight | 2150 |
| 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 | 3 |
| Number of Engines | 1 |
| Fixed gear or retractable gear | Fixed |
| Aircraft, Type of Last Inspection | Annual |
| Date of Last Inspection | Feb 2 2001 12:00AM |
| Airframe hours since last inspection | 1 |
| Airframe Hours | 1732 |
| ELT Installed | No |
| ELT Activated | No |
| ELT Aided Location of Event Site | No |
| ELT Type | -- |
| Aircraft Owner Name | William E. Bolin |
| Aircraft Owner Street Address | -- |
| Aircraft Owner City | Napolean |
| Aircraft Owner State | OH |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 43545 |
| 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) | Other Work Use |
| Second Pilot on Board | No |
| Departure Point Same as Event | Yes |
| Departure Airport Code | 7W5 |
| Departure City | Napolean |
| Departure State | OH |
| Departure Country | USA |
| Departure Time | 1120 |
| Departure Time Zone | EST |
| 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 | Approach - VFR pattern - final approach |
| Report sent to ICAO? | No |
| Evacuation occurred | No |
| Date of most recent change to record | Feb 4 2002 10:03AM |
| User who most recently changed record | PEAR |
| Since inspection or accident | Time of Accident |
| Event Location Runway Number and Location | 10 |
| Runway Length | 4487 |
| Runway Width | 65 |
| Sight Seeing flight | Yes |
| Air Medical Flight | No |
| Medical Flight | -- |