Individually Owned: 150,657
Corporate Owned: 137,281
Aircraft Accident/Incident Report
Navarre, Florida 32566
Thursday, June 8, 2006 12:32 CDT
NTSB Narrative Summary Released at Completion of Accident
While flying in straight and level flight at 600 feet and approximately 100 miles-per-hour, undetected fatigue cracks in the stainless steel plates of one of the tail rotor blade tension-torsion bars resulted in in-flight separation of one tail rotor blade, and subsequent structural separation of a portion of the ventral fin. The pilot executed an autorotative landing to shallow water and there were no injuries to the pilot or pilot-rated passenger. Eight of the 11 stainless steel plates of the tension-torsion bar assembly exhibited fatigue which originated from stress risers created during the manufacturing process (punching) of the holes of the plates. Reaming of the holes did not eliminate the surface created during the punching process. This problem was previously noted to exist and corrective action was taken in the form of an airworthiness directive (AD), but the AD was not applicable to the accident helicopter because the serial number of the accident tension-torsion bars was outside of the scope of the AD.
NTSB Probable Cause Narrative
The inadequate manufacturing of the plates of the tail rotor tension-torsion bar assembly resulting in fatigue failure.
Event Information
| Type of Event | Accident |
| Event Date | 6/8/2006 |
| Event Day of the Week | Thursday |
| Time of Event | 1232 |
| Event Time Zone | Central Daylight Time |
| Event City | Navarre |
| Event State | FLORIDA |
| Event Country | -- |
| Zipcode of the event site | 32566 |
| Event Date Year | 2006 |
| Event Date Month | 6 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 302235N |
| Event Location Longitude | 0865440W |
| 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 | Weather Observation Facility |
| Time of the weather observation | 1253 Central Daylight Time |
| Direction of event from weather observation facility (degrees) | -- |
| Weather Observation Facility ID | PNS |
| Elevation of weather observation facility | 121 |
| Distance of event from weather observation facility (units?) | -- |
| Time Zone of the weather observation | CDT |
| Lighting Conditions | Day |
| Lowest Ceiling Height | -- |
| Lowest Non-Ceiling Height | 6000 |
| Sky/Lowest/Cloud Conditions | Few |
| 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) | 31 |
| Dew Point at event time (in degress fahrenheit) | 19 |
| Wind Direction (degrees magnetic) | 70 |
| Variable Wind Indicator | Wind direction could be determined |
| Wind Speed (knots) | 5 |
| Wind Velocity Indicator | -- |
| Wind Gust Indicator | Not Gusting |
| Wind Gust (knots) | -- |
| Altimeter Setting at event time (in. Hg) | 29.96 |
| Density Altitude (feet) | -- |
| Intensity of Precipitation | -- |
| METAR weather report | -- |
| 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 | 2 |
| Injury Total Serious | -- |
| Injury Total All | -- |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 22484 |
| NTSB Notification Source | Santa Rosa County SD |
| NTSB Notification Date | Jun 8 2006 12:00AM |
| NTSB Notification Time | -- |
| Fiche Number and/or location -used to find docket information | DMS |
| Date of most recent change to record | Nov 29 2007 8:02AM |
| User who most recently changed record | NTSB\johb |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | Birmingham, Alabama |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N4035G |
| NTSB Number | MIA06LA126 |
| 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 | Fairchild Hiller |
| Aircraft Model | FH-1100 |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | 502 |
| Certified Max Gross Weight | 2750 |
| Aircraft Category | Helicopter |
| Aircraft Registration Class | -- |
| 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 | Jan 1 2006 12:00AM |
| Airframe hours since last inspection | 97 |
| Airframe Hours | 370 |
| ELT Installed | No |
| ELT Activated | No |
| ELT Aided Location of Event Site | No |
| ELT Type | -- |
| Aircraft Owner Name | Helicopters of NW Florida, Inc. |
| Aircraft Owner Street Address | 8494 Navarre Parkway |
| Aircraft Owner City | Navarre |
| Aircraft Owner State | FL |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 32566 |
| 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) | Instructional |
| Second Pilot on Board | Yes |
| Departure Point Same as Event | No |
| Departure Airport Code | 52FD |
| Departure City | Navarre |
| Departure State | FL |
| Departure Country | USA |
| Departure Time | 1225 |
| Departure Time Zone | CDT |
| Destination Same as Local Flt | -- |
| Destination Airport Code | -- |
| Destination City | Century |
| Destination State | FL |
| Destination Country | USA |
| Specific Phase of Flight | Cruise - normal |
| Report sent to ICAO? | -- |
| Evacuation occurred | -- |
| Date of most recent change to record | Oct 17 2007 10:27AM |
| User who most recently changed record | KENJ |
| Since inspection or accident | Last Inspection |
| Event Location Runway Number and Location | NA |
| Runway Length | -- |
| Runway Width | -- |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |