Individually Owned: 150,657
Corporate Owned: 137,281
Aircraft Accident/Incident Report
Marathon, Florida 33050
Friday, April 22, 1994 11:28 EDT
NTSB Narrative Summary Released at Completion of Accident
WITNESSES HEARD A LOUD NOISE AS THE HELICOPTER WAS FLYING AT 100' TO 150' AGL & SAW SOMETHING FALL FROM THE TAIL BOOM. THE HELICOPTER IMMEDIATELY NOSED DOWN & BEGAN SPINNING TO THE RIGHT. IT IMPACTED ON A ROCK ISLAND & CAME TO REST IN WATER NEXT TO THE ISLAND. THE TAIL ROTOR GEARBOX, TAIL ROTOR HUB & ONE TAIL ROTOR BLADE WERE NOT LOCATED AFTER THE ACCIDENT. ONE TAIL ROTOR BLADE WAS FOUND ALONG THE FLIGHTPATH IN 2 PIECES, ABOUT 150' FROM THE MAIN WRECKAGE. THE TAIL ROTOR GEARBOX HAD SEPARATED DUE TO OVERSTRESS; ALL FRACTURES OF THE RECOVERED TAIL ROTOR BLADE WERE TYPICAL OF OVER- STRESS. THE TAIL ROTOR BLADE HAD NO IMPACT MARKS ON THE LEADING EDGE OR TIP. NO PRECRASH FAILURE/MALFUNCTION OF THE REMAINING STRUCTURE, FLIGHT CONTROLS, MAIN ROTOR BLADES, TRANSMISSION OR ENGINE WAS FOUND. A TAIL ROTOR STRIKE OCCURRED 130 FLIGHT HRS BEFORE THE ACCIDENT; THE TAIL ROTOR BLADES WERE CHANGED, BUT THE HUB WAS NOT CHANGED AS REQUIRED BY THE MANUFACTURER'S INSTRUCTION. THOUGH OPERATING FOR HIRE, HELICOPTER HAD FLOWN 130 HRS SINCE THE LAST MAINTENANCE INSPECTION. CALCULATIONS SHOWED THAT DURING TAKEOFF, THE HELICOPTER'S CG WAS 3.4' FORWARD OF THE FORWARD LIMIT. WITH LOSS OF THE SEPARATED PARTS, THE CG WOULD HAVE MOVED ABOUT 2' FURTHER FORWARD.
NTSB Probable Cause Narrative
SEPARATION OF THE TAIL ROTOR GEARBOX AND TAIL ROTOR BLADES FOR AN UNDETERMINED REASON. FACTORS RELATED TO THE ACCIDENT WERE: FAILURE OF MAINTENANCE PERSONNEL TO FOLLOW THE PROPER MAINTENANCE PROCEDURE AFTER A PREVIOUS TAIL ROTOR STRIKE, AND FAILURE TO CONDUCT A 100-HOUR INSPECTION WHEN DUE.
Event Information
| Type of Event | Accident |
| Event Date | 4/22/1994 |
| Event Day of the Week | Friday |
| Time of Event | 1128 |
| Event Time Zone | Eastern Daylight Time |
| Event City | MARATHON |
| Event State | FLORIDA |
| Event Country | -- |
| Zipcode of the event site | 33050 |
| Event Date Year | 1994 |
| Event Date Month | 4 |
| 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 | Unknown |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 1152 Eastern Daylight Time |
| Direction of event from weather observation facility (degrees) | 265 |
| Weather Observation Facility ID | EYW |
| Elevation of weather observation facility | 4 |
| Distance of event from weather observation facility (units?) | 42 |
| Time Zone of the weather observation | EDT |
| Lighting Conditions | Day |
| Lowest Ceiling Height | 20000 |
| Lowest Non-Ceiling Height | 2000 |
| Sky/Lowest/Cloud Conditions | Scattered |
| Sky Condition for Lowest Ceiling | Broken |
| 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) | 29 |
| Dew Point at event time (in degress fahrenheit) | 24 |
| Wind Direction (degrees magnetic) | 170 |
| 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) | 29 |
| Density Altitude (feet) | 1000 |
| 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 | 2 |
| Injury Total Minor | -- |
| Injury Total None | -- |
| Injury Total Serious | 1 |
| Injury Total All | 3 |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 684 |
| NTSB Notification Source | -- |
| NTSB Notification Date | Apr 22 1994 12:00AM |
| NTSB Notification Time | 1240 |
| Fiche Number and/or location -used to find docket information | IMAGE |
| Date of most recent change to record | Dec 6 2000 11:03AM |
| User who most recently changed record | dbo |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | -- |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N9660 |
| NTSB Number | MIA94FA125 |
| 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 | BELL |
| Aircraft Model | 47D1 |
| Aircraft Series Identifier | 47D1 |
| Aircraft Serial Number | 486 |
| Certified Max Gross Weight | 2350 |
| 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 | AAIP |
| Date of Last Inspection | Mar 10 1994 12:00AM |
| Airframe hours since last inspection | 105 |
| Airframe Hours | 7502 |
| ELT Installed | Yes |
| ELT Activated | No |
| ELT Aided Location of Event Site | Unknown |
| ELT Type | -- |
| Aircraft Owner Name | NEW TROPICAL ADVENTURES, INC. |
| Aircraft Owner Street Address | 12648 OVERSEAS HIGHWAY |
| Aircraft Owner City | MARATHON |
| Aircraft Owner State | FL |
| Aircraft Owner Country | |
| Aircraft Owner Zipcode | 33050 |
| 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) | Unknown |
| Second Pilot on Board | No |
| Departure Point Same as Event | Yes |
| Departure Airport Code | |
| Departure City | |
| Departure State | |
| Departure Country | |
| Departure Time | 1118 |
| Departure Time Zone | EDT |
| 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 |
| Report sent to ICAO? | -- |
| Evacuation occurred | -- |
| Date of most recent change to record | Aug 22 2001 3:51PM |
| 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 | Yes |
| Air Medical Flight | No |
| Medical Flight | -- |