Individually Owned: 150,657
Corporate Owned: 137,281
Aircraft Accident/Incident Report
Salinas, California 93905
Saturday, November 20, 1993 8:45 PST
NTSB Narrative Summary Released at Completion of Accident
DURING A SWATH RUN TO APPLY A MIXTURE OF PESTICIDES, THE PILOT HEARD A LOUD 'POP'. THE HELICOPTER'S COLLECTIVE CONTROL BEGAN TO OSCILLATE AND THE AIRCRAFT EXPERIENCED A SEVERE VIBRATION. THE HELICOPTER ALSO BEGAN TO OSCILLATE AND THE PILOT SLOWED TO ABOUT 15 KNOTS AND ATTEMPTED TO LAND. A SPRAY BOOM ATTACHED TO THE HELICOPTER CONTACTED THE GROUND AND THE HELICOPTER ROLLED ON ITS LEFT SIDE. EXAMINATION REVEALED THE PRESENCE OF FRETTING CORROSION AND A FATIGUE FAILURE OF THE TENSION-TORSION BAR PIN, INTO WHICH THE MAIN ROTOR BLADE DRAG BRACE IS ATTACHED. A SECOND TENSION-TORSION PIN FROM A SISTER HELICOPTER WAS DISCOVERED TO ALSO HAVE CORROSION AND A FATIGUE CRACK. PINS FAILED AT 369.5 HOURS AND 489.4 HOURS RESPECTIVELY. THE RETIREMENT LIFE OF THE PIN IS 643 HOURS.
NTSB Probable Cause Narrative
a fatigue failure of the torsion-tension bar pin due to fretting corrosion. A factor in this accident was an inadequate quality of material utilized in the manufacture of the pin.
Event Information
| Type of Event | Accident |
| Event Date | 11/20/1993 |
| Event Day of the Week | Saturday |
| Time of Event | 845 |
| Event Time Zone | Pacific Standard Time |
| Event City | SALINAS |
| Event State | CALIFORNIA |
| Event Country | -- |
| Zipcode of the event site | 93905 |
| Event Date Year | 1993 |
| Event Date Month | 11 |
| 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 | 815 Pacific Standard Time |
| Direction of event from weather observation facility (degrees) | 315 |
| Weather Observation Facility ID | SNS |
| Elevation of weather observation facility | 84 |
| Distance of event from weather observation facility (units?) | 8 |
| Time Zone of the weather observation | PST |
| Lighting Conditions | Day |
| Lowest Ceiling Height | 20000 |
| Lowest Non-Ceiling Height | 20000 |
| Sky/Lowest/Cloud Conditions | Unknown |
| Sky Condition for Lowest Ceiling | Overcast |
| Visibility Runway Visual Range (Feet) | 0 |
| Visibility Runway Visual Value (Statute Miles) | 0 |
| Visibility (Statute Miles) | 35 |
| Air Temperature at event time (in degrees celsius) | 9 |
| Dew Point at event time (in degress fahrenheit) | 2 |
| Wind Direction (degrees magnetic) | 120 |
| Variable Wind Indicator | Unknown |
| Wind Speed (knots) | 10 |
| Wind Velocity Indicator | Unknown |
| Wind Gust Indicator | Not Gusting |
| Wind Gust (knots) | 0 |
| Altimeter Setting at event time (in. Hg) | 30 |
| Density Altitude (feet) | -- |
| 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 | NTSB |
| NTSB Docket Number (internal use) | 1754 |
| NTSB Notification Source | -- |
| NTSB Notification Date | Nov 20 1993 12:00AM |
| NTSB Notification Time | 1000 |
| Fiche Number and/or location -used to find docket information | IMAGE |
| Date of most recent change to record | Dec 11 2000 1:45PM |
| User who most recently changed record | dbo |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | -- |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N161HA |
| NTSB Number | LAX94LA054 |
| 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 | HA-3061 |
| 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 | 100 Hour |
| Date of Last Inspection | Oct 14 1993 12:00AM |
| Airframe hours since last inspection | 74 |
| Airframe Hours | 7725 |
| ELT Installed | No |
| ELT Activated | Unknown |
| ELT Aided Location of Event Site | Unknown |
| ELT Type | -- |
| Aircraft Owner Name | R AND B HELICOPTERS |
| Aircraft Owner Street Address | 240 MORTENSEN AVE. |
| Aircraft Owner City | SALINAS |
| Aircraft Owner State | CA |
| Aircraft Owner Country | |
| Aircraft Owner Zipcode | 93905 |
| Operator is an individual? | -- |
| Operator Name | R AND B HELICOPTERS INC. |
| Operator Same as Owner? | Yes |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | Yes |
| Operator Street Address | 240 MORTENSEN AVE. |
| Operator City | SALINAS |
| Operator State | CA |
| Operator Country | |
| Operator Zip code | 93905 |
| Operator Code | CBFG |
| 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 | Yes |
| Departure Airport Code | |
| Departure City | |
| Departure State | |
| Departure Country | |
| Departure Time | 844 |
| Departure Time Zone | PST |
| 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 | Landing |
| 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 | -- |