Individually Owned: 150,657
Corporate Owned: 137,281
Aircraft Accident/Incident Report
La Grande, Oregon 97850
Friday, July 4, 2003 8:50 PDT
NTSB Narrative Summary Released at Completion of Accident
During an aerial application flight, the pilot reported that during a turn he heard and felt three or four "clunking sounds in the airframe." The pilot continued the pedal turn to the left and then straightened out to approach a field. Rotor rpm was deteriorating as he attempted to auto rotate to the field. The pilot stated that he had "no auto-rotating capability" and landed hard in the field. The helicopter bounced once then touched down again coming to rest on its left side. A post-crash fire consumed the wreckage. On site inspection of the wreckage found that the free wheeling side of the clutch assembly and the main drive shaft assembly nut were disconnected. The items were sent to the NTSB materials laboratory for further inspection. The specialist reported that the drive from the main rotor gearbox to the clutch was severed when the bearing support separated from the drive housing. The threads on the bearing support displayed a shearing off of the crown of the forward full form thread. The flanks of the threads to the rear of the sheared thread displayed no indications of contact by the mating thread on the drive housing. Mechanical damage to the threads on the drive housing was limited to the first two rearmost threads. The flanks of the threads forward of the damaged threads displayed no indications of contact by the mating thread on the bearing support. Deformation of the rear ends of the splines forward of the threads and of the two rearmost threads indicate that it was not fully engaged with the drive housing.
NTSB Probable Cause Narrative
The cross threading and separation of the clutch assembly while maneuvering which resulted in a loss of engine power followed by a hard landing. An inadequate maintenance overhaul was a factor.
Event Information
| Type of Event | Accident |
| Event Date | 7/4/2003 |
| Event Day of the Week | Friday |
| Time of Event | 850 |
| Event Time Zone | Pacific Daylight Time |
| Event City | La Grande |
| Event State | OREGON |
| Event Country | -- |
| Zipcode of the event site | 97850 |
| Event Date Year | 2003 |
| Event Date Month | 7 |
| MidAir Collision Indicator | -- |
| On Ground Collision occurred ? | -- |
| Event Location Latitude | 451900N |
| Event Location Longitude | 1175200W |
| 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 | 915 Pacific Daylight Time |
| Direction of event from weather observation facility (degrees) | 230 |
| Weather Observation Facility ID | LGD |
| Elevation of weather observation facility | 2717 |
| Distance of event from weather observation facility (units?) | 5 |
| Time Zone of the weather observation | PDT |
| Lighting Conditions | Day |
| Lowest Ceiling Height | -- |
| Lowest Non-Ceiling Height | -- |
| Sky/Lowest/Cloud Conditions | Clear |
| 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) | 17 |
| Dew Point at event time (in degress fahrenheit) | 3 |
| Wind Direction (degrees magnetic) | -- |
| Variable Wind Indicator | -- |
| Wind Speed (knots) | -- |
| Wind Velocity Indicator | Calm |
| Wind Gust Indicator | Not Gusting |
| Wind Gust (knots) | -- |
| Altimeter Setting at event time (in. Hg) | 30.13 |
| 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 | 1 |
| Injury Total Serious | -- |
| Injury Total All | -- |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 15582 |
| NTSB Notification Source | FAA Regional Operations Center |
| NTSB Notification Date | Jul 4 2003 12:00AM |
| NTSB Notification Time | 924 |
| Fiche Number and/or location -used to find docket information | DMS |
| Date of most recent change to record | Jun 3 2004 1:28PM |
| User who most recently changed record | NTSB\MONR |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | Boise, Idaho |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N37799 |
| NTSB Number | SEA03LA125 |
| Missing Aircraft Indicator | -- |
| Federal Aviation Reg. Part | Part 137: Agricultural |
| Type of Flight Plan filed | None |
| Flight plan Was Activated? | No |
| Damage | Destroyed |
| Aircraft Fire | Ground |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | Sikorsky |
| Aircraft Model | UH-19D |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | 56-1542 |
| Certified Max Gross Weight | 7900 |
| 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 | 2 |
| Number of Engines | 1 |
| Fixed gear or retractable gear | Fixed |
| Aircraft, Type of Last Inspection | AAIP |
| Date of Last Inspection | Sep 4 2002 12:00AM |
| Airframe hours since last inspection | 114 |
| Airframe Hours | -- |
| ELT Installed | No |
| ELT Activated | No |
| ELT Aided Location of Event Site | No |
| ELT Type | -- |
| Aircraft Owner Name | Americopter Aviation Services |
| Aircraft Owner Street Address | 60272 Pierce Rd |
| Aircraft Owner City | La Grande |
| Aircraft Owner State | OR |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 97850 |
| 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 | -- |
| Other Operator of large aircraft? | -- |
| Certified for Part 133 or 137 Operation | Agriculture |
| 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) | Aerial Application |
| Second Pilot on Board | No |
| Departure Point Same as Event | No |
| Departure Airport Code | LGD |
| Departure City | La Grande |
| Departure State | OR |
| Departure Country | USA |
| Departure Time | -- |
| Departure Time Zone | -- |
| 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 | Maneuvering - aerial application |
| Report sent to ICAO? | No |
| Evacuation occurred | No |
| Date of most recent change to record | Apr 13 2004 10:38AM |
| User who most recently changed record | STAM |
| Since inspection or accident | -- |
| Event Location Runway Number and Location | -- |
| Runway Length | -- |
| Runway Width | -- |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |