Individually Owned: 150,657
Corporate Owned: 137,281
Aircraft Accident/Incident Report
Hudsonville, Michigan 49426
Thursday, September 28, 1989 7:45 EDT
NTSB Narrative Summary Released at Completion of Accident
APPROXIMATELY 10 MINUTES AFTER TAKEOFF AT AN ALTITUDE OF 300 FT AGL AND AN AIRSPEED OF 60 KTS, THE PILOT EXPERIENCED A SEVERE VIBRATION AND A DECREASE IN RESPONSE TO CONTROL INPUTS. THE PILOT ENTERED AN AUTOROTATION AND WHEN APPROXIMATELY 10 - 15 FT AGL, THE TAIL BOOM WAS SEPARATED BY THE MAIN ROTOR. THE HELICOPTER THEN DESCENDED, NOSE FIRST, TO TERRAIN IMPACT. INSPECTION REVEALED A TENSION-TORSION PIN HAD FAILED AT THE DRAG BRACE BOLT HOLE. PRE-EXISTING CRACKS WERE FOUND EXTENDING FROM THE PIN SHANK TO THE BOLT HOLE.
NTSB Probable Cause Narrative
THE FATIGUE FAILURE OF ONE OF THE TENSION-TORSION PINS.
Event Information
| Type of Event | Accident |
| Event Date | 9/28/1989 |
| Event Day of the Week | Thursday |
| Time of Event | 745 |
| Event Time Zone | Eastern Daylight Time |
| Event City | HUDSONVILLE |
| Event State | MICHIGAN |
| Event Country | -- |
| Zipcode of the event site | 49426 |
| Event Date Year | 1989 |
| Event Date Month | 9 |
| 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 | 0 |
| Degrees magnetic from airport | 0 |
| Airport Elevation | -- |
| Weather Briefing Completeness | Unknown |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 750 Eastern Daylight Time |
| Direction of event from weather observation facility (degrees) | 80 |
| Weather Observation Facility ID | GRR |
| Elevation of weather observation facility | 794 |
| Distance of event from weather observation facility (units?) | 18 |
| Time Zone of the weather observation | EDT |
| 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) | 15 |
| Air Temperature at event time (in degrees celsius) | 8 |
| Dew Point at event time (in degress fahrenheit) | 4 |
| Wind Direction (degrees magnetic) | 210 |
| Variable Wind Indicator | Unknown |
| Wind Speed (knots) | 7 |
| Wind Velocity Indicator | Unknown |
| Wind Gust Indicator | Not Gusting |
| Wind Gust (knots) | 0 |
| Altimeter Setting at event time (in. Hg) | 30 |
| Density Altitude (feet) | 300 |
| Intensity of Precipitation | Unknown |
| METAR weather report | -- |
| Event Highest Injury | Minor |
| On Ground, Fatal Injuries | 0 |
| On Ground, Minor Injuries | 0 |
| On Ground, Serious Injuries | 0 |
| Injury Total Fatal | -- |
| Injury Total Minor | 1 |
| Injury Total None | -- |
| Injury Total Serious | -- |
| Injury Total All | 1 |
| Investigating Agency | FAA |
| NTSB Docket Number (internal use) | 2163 |
| NTSB Notification Source | -- |
| NTSB Notification Date | Sep 28 1989 12:00AM |
| NTSB Notification Time | 830 |
| Fiche Number and/or location -used to find docket information | 41841 |
| Date of most recent change to record | Dec 13 2000 1:02PM |
| User who most recently changed record | dbo |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | -- |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N4028T |
| NTSB Number | CHI89DEM09 |
| Missing Aircraft Indicator | N |
| Federal Aviation Reg. Part | Part 137: Agricultural |
| Type of Flight Plan filed | None |
| Flight plan Was Activated? | -- |
| Damage | Substantial |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | HILLER |
| Aircraft Model | UH-12E |
| Aircraft Series Identifier | UH-12E |
| Aircraft Serial Number | 5097 |
| Certified Max Gross Weight | 3100 |
| 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 18 1989 12:00AM |
| Airframe hours since last inspection | 77 |
| Airframe Hours | 1197 |
| ELT Installed | No |
| ELT Activated | No |
| ELT Aided Location of Event Site | No |
| ELT Type | -- |
| Aircraft Owner Name | BYRON AG AVIATION, INC. |
| Aircraft Owner Street Address | P.O. BOX 49 |
| Aircraft Owner City | BYRON CENTER |
| Aircraft Owner State | MI |
| Aircraft Owner Country | |
| Aircraft Owner Zipcode | 49315 |
| 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 | BYRG |
| Owner has at least one certificate | Yes - certificate holder |
| Other Operator of large aircraft? | No |
| Certified for Part 133 or 137 Operation | Agriculture |
| Operator Certificate Number | -- |
| Indicates whether an air carrier operation was scheduled or not | Unknown |
| Indicates Domestic or International Flight | Unknown |
| Operator carrying Pax/Cargo/Mail | Unknown |
| Type of Flying (Per_Bus / Primary) | Aerial Application |
| Second Pilot on Board | No |
| Departure Point Same as Event | No |
| Departure Airport Code | NONE |
| Departure City | BYRON CENTER |
| Departure State | MI |
| Departure Country | |
| Departure Time | 730 |
| Departure Time Zone | EDT |
| Destination Same as Local Flt | -- |
| Destination Airport Code | NONE |
| Destination City | HUDSONVILLE |
| 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 10:35AM |
| 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 | -- |