Individually Owned: 150,657
Corporate Owned: 137,281
Winnie/Stowell Airport
Aircraft Accident/Incident Report
Winnie, Texas 77665
Friday, August 19, 2005 11:00 CDT
NTSB Narrative Summary Released at Completion of Accident
The 18,950-hour commercial pilot reported that that shortly after departure the "engine blew" and he executed a forced landing to a field, and the airplane received minor damage. Examination of the turbine engine revealed that it had experienced an uncontained separation of the second-stage turbine disk as a result of low cycle fatigue. No evidence of deep scratches or gouges were observed on the bore surface or on the forward and aft face of the disk. A review of maintenance records revealed that the engine had been previously installed on an aircraft that was registered in a foreign country, and the maintenance records were not complete. When the operator purchased this engine, he informed the facility that performed his engine maintenance that the second-stage turbine rotor was installed on the engine in 1992 with a total of 730 cycles. The maintenance facility then produced a new life-limit card for the second stage turbine disk. Based on this data, the disk had accrued a total of approximately 1,738 cycles at the time it failed. The rotor had an FAA approved life-limit of 5,400 cycles. However, according to the production records from the manufacturer of the engine, the second-stage turbine rotor had originally been shipped with zero hours and cycles in another, new production engine on January 24, 1973, making the part 33 years old.
NTSB Probable Cause Narrative
The loss of engine power due to the failure of the second-stage turbine wheel as a result of low cycle fatigue.
Event Information
| Type of Event | Incident |
| Event Date | 8/19/2005 |
| Event Day of the Week | Friday |
| Time of Event | 1100 |
| Event Time Zone | Central Daylight Time |
| Event City | Winnie |
| Event State | TEXAS |
| Event Country | -- |
| Zipcode of the event site | 77665 |
| Event Date Year | 2005 |
| Event Date Month | 8 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 294808N |
| Event Location Longitude | 0942531W |
| Event Location Airport | Winnie/Stowell Airport |
| Event Location Nearest Airport ID | T90 |
| Indicates whether the acc/inc occurred off or on an airport | Off Airport/Airstrip |
| Distance from airport in statute miles | 1 |
| Degrees magnetic from airport | -- |
| Airport Elevation | 25 |
| Weather Briefing Completeness | -- |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 1053 Central Standard Time |
| Direction of event from weather observation facility (degrees) | 330 |
| Weather Observation Facility ID | BOT |
| Elevation of weather observation facility | 15 |
| Distance of event from weather observation facility (units?) | 23 |
| Time Zone of the weather observation | CST |
| 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) | 33 |
| Dew Point at event time (in degress fahrenheit) | 24 |
| Wind Direction (degrees magnetic) | 220 |
| Variable Wind Indicator | Wind direction could be determined |
| Wind Speed (knots) | 6 |
| Wind Velocity Indicator | -- |
| Wind Gust Indicator | Unknown |
| Wind Gust (knots) | -- |
| Altimeter Setting at event time (in. Hg) | 30.04 |
| 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) | 20069 |
| NTSB Notification Source | HOU FSDO |
| NTSB Notification Date | Aug 19 2005 12:00AM |
| NTSB Notification Time | -- |
| Fiche Number and/or location -used to find docket information | DMS |
| Date of most recent change to record | Jul 31 2006 10:47AM |
| User who most recently changed record | NTSB\JOHB |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | Houston, Texas |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N4545W |
| NTSB Number | DFW05IA222 |
| Missing Aircraft Indicator | -- |
| Federal Aviation Reg. Part | Part 91: General Aviation |
| Type of Flight Plan filed | None |
| Flight plan Was Activated? | No |
| Damage | Minor |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | Air Tractor |
| Aircraft Model | AT-401 |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | 401-0790 |
| Certified Max Gross Weight | 7860 |
| Aircraft Category | Airplane |
| Aircraft Registration Class | -- |
| Aircraft is a homebuilt? | No |
| Flight Crew Seats | -- |
| Cabin Crew Seats | -- |
| Passenger Seats | -- |
| Total number of seats on the aircraft | 1 |
| Number of Engines | 1 |
| Fixed gear or retractable gear | Fixed |
| Aircraft, Type of Last Inspection | Annual |
| Date of Last Inspection | Apr 1 2005 12:00AM |
| Airframe hours since last inspection | -- |
| Airframe Hours | -- |
| ELT Installed | No |
| ELT Activated | No |
| ELT Aided Location of Event Site | No |
| ELT Type | -- |
| Aircraft Owner Name | Twin County Air Ag, Incorporated |
| Aircraft Owner Street Address | PO Box 1268 |
| Aircraft Owner City | Winnie |
| Aircraft Owner State | TX |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 77665 |
| 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) | Positioning |
| Second Pilot on Board | No |
| Departure Point Same as Event | No |
| Departure Airport Code | T90 |
| Departure City | Winnie |
| Departure State | TX |
| Departure Country | USA |
| Departure Time | 1055 |
| Departure Time Zone | CDT |
| Destination Same as Local Flt | -- |
| Destination Airport Code | ARM |
| Destination City | Wharton |
| Destination State | TX |
| Destination Country | USA |
| Specific Phase of Flight | Climb - to cruise |
| Report sent to ICAO? | -- |
| Evacuation occurred | -- |
| Date of most recent change to record | May 17 2006 9:17AM |
| User who most recently changed record | CASH |
| Since inspection or accident | -- |
| Event Location Runway Number and Location | NA |
| Runway Length | -- |
| Runway Width | -- |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |