Individually Owned: 150,657
Corporate Owned: 137,281
Aircraft Accident/Incident Report
Dewitt, Michigan 48820
Friday, August 14, 1998 16:20 EDT
NTSB Narrative Summary Released at Completion of Accident
A Hiller FH-1100 was destroyed on impact with terrain following the separation of a tail rotor blade in cruise flight. The tail rotor blade 'B' was separated 1/4 span from its root and was discovered 700 feet south of the main wreckage. Blade 'A' was found 850 feet south of the main wreckage. The tail rotor blades were overhauled and later removed for blade delamination on July 14, 1986. The inside surfaces of the blade 'A's' skin showed longitudinal streak patterns of debris. The skin trailing edge closure bond contained an adhesive that was bright purple in color. During 1967-1982 tail rotor blades were bonded with FM1000; a cream or off white colored adhesive. Since 1982, FM1000 bonded the skin and doubler and FM73, which is orange brown in color, between the root fitting and doubler. The rivet holes in the skin were worn on the skin surfaces under the upset heads of the rivets. No wear was visible under the manufactured heads. The rivet holes were not round and appeared to have two overlapping diameters consistent with double drilling. The Hiller FH1100 Overhaul Manual Tail Rotor Assembly, Repair - Tail Rotor Blade Assembly, states, '...Replacement of skin, doubler or rib ... is not permitted.' The Hiller FH1100 Inspection Guide described the inspection of the tail rotor blades during preflight, 100-hour inspection and 300-hour inspection.
NTSB Probable Cause Narrative
The rotor failure/malfunction due to debonding of the tail rotor blade. Also causal was the inadequate maintenance inspection of the aircraft by the company and the improper maintenance procedure by other maintenance personnel.
Event Information
| Type of Event | Accident |
| Event Date | 8/14/1998 |
| Event Day of the Week | Friday |
| Time of Event | 1620 |
| Event Time Zone | Eastern Daylight Time |
| Event City | DEWITT |
| Event State | MICHIGAN |
| Event Country | -- |
| Zipcode of the event site | 48820 |
| Event Date Year | 1998 |
| Event Date Month | 8 |
| 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 | Weather Observation Facility |
| Time of the weather observation | 1555 |
| Direction of event from weather observation facility (degrees) | 30 |
| Weather Observation Facility ID | LAN |
| Elevation of weather observation facility | 861 |
| Distance of event from weather observation facility (units?) | 17 |
| Time Zone of the weather observation | |
| Lighting Conditions | Day |
| Lowest Ceiling Height | 0 |
| Lowest Non-Ceiling Height | 7500 |
| Sky/Lowest/Cloud Conditions | Scattered |
| 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) | 27 |
| Dew Point at event time (in degress fahrenheit) | 14 |
| Wind Direction (degrees magnetic) | 210 |
| Variable Wind Indicator | Unknown |
| Wind Speed (knots) | 8 |
| Wind Velocity Indicator | Unknown |
| Wind Gust Indicator | Unknown |
| Wind Gust (knots) | 0 |
| Altimeter Setting at event time (in. Hg) | 29 |
| Density Altitude (feet) | -- |
| Intensity of Precipitation | Unknown |
| METAR weather report | -- |
| Event Highest Injury | Fatal |
| On Ground, Fatal Injuries | 0 |
| On Ground, Minor Injuries | 0 |
| On Ground, Serious Injuries | 0 |
| Injury Total Fatal | 1 |
| Injury Total Minor | -- |
| Injury Total None | -- |
| Injury Total Serious | -- |
| Injury Total All | 1 |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 1707 |
| NTSB Notification Source | -- |
| NTSB Notification Date | Aug 14 1998 12:00AM |
| NTSB Notification Time | 2032 |
| Fiche Number and/or location -used to find docket information | IMAGE |
| Date of most recent change to record | Dec 11 2000 11:41AM |
| User who most recently changed record | dbo |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | -- |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N8171U |
| NTSB Number | CHI98FA313 |
| Missing Aircraft Indicator | N |
| Federal Aviation Reg. Part | Part 91: General Aviation |
| Type of Flight Plan filed | None |
| Flight plan Was Activated? | -- |
| Damage | Destroyed |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | Hiller |
| Aircraft Model | FH-1100 |
| Aircraft Series Identifier | FH-1100 |
| Aircraft Serial Number | 254 |
| Certified Max Gross Weight | 3000 |
| 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 | 5 |
| Number of Engines | 1 |
| Fixed gear or retractable gear | Fixed |
| Aircraft, Type of Last Inspection | Annual |
| Date of Last Inspection | Feb 1 1997 12:00AM |
| Airframe hours since last inspection | 135 |
| Airframe Hours | 3821 |
| ELT Installed | Yes |
| ELT Activated | Yes |
| ELT Aided Location of Event Site | No |
| ELT Type | -- |
| Aircraft Owner Name | HORIZON HELICOPTERS INC |
| Aircraft Owner Street Address | 9415 NIXON |
| Aircraft Owner City | GRAND LEDGE |
| Aircraft Owner State | MI |
| Aircraft Owner Country | |
| Aircraft Owner Zipcode | 48837 |
| 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) | Business |
| Second Pilot on Board | No |
| Departure Point Same as Event | No |
| Departure Airport Code | |
| Departure City | GRAND LEDGE |
| Departure State | MI |
| Departure Country | |
| Departure Time | 1607 |
| Departure Time Zone | EDT |
| Destination Same as Local Flt | -- |
| Destination Airport Code | |
| Destination City | ST. JOHNS |
| Destination State | MI |
| Destination Country | |
| Specific Phase of Flight | Cruise |
| Report sent to ICAO? | -- |
| Evacuation occurred | -- |
| Date of most recent change to record | Jan 2 2001 10:34AM |
| 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 | -- |