Individually Owned: 150,657
Corporate Owned: 137,281
None Airport
Aircraft Accident/Incident Report
Millsap, Texas 76066
Sunday, August 7, 2011 13:33 CDT
NTSB Narrative Summary Released at Completion of Accident
The pilot had just leveled off to cruise flight when the airplane jerked and began to vibrate violently. The pilot secured the engine and made a forced landing on a road. A postaccident examination revealed that an 18-inch section of one of the propeller blades had separated. Metallurgical examination of the remaining blade section revealed striations on the fracture surface consistent with high-cycle fatigue. At least three crack arrest marks were observed, which was consistent with the stopping and starting of the cyclic stresses. The propeller had accumulated 165.73 hours since being overhauled in 2004. The most recent 100-hour inspection was completed about 10 months before the accident. The Federal Aviation Administration issued Airworthiness Directive (AD) 69-09-03 R3 in 1996 to prevent propeller blade tip fatigue failure. The directive required that pilots avoid continuous operation between 2150 and 2350 rpm. The failure mode of the blade was consistent with it operating in the restricted rpm range. Due to the multiple arrest marks found in the examination, the fatigue crack had propagated over multiple flight cycles. It could not be determined when the fatigue crack was initiated.
NTSB Probable Cause Narrative
A sudden loss of engine thrust due to the separation of a propeller blade in cruise flight due to high cycle fatigue.
Event Information
| Type of Event | Accident |
| Event Date | 8/7/2011 |
| Event Day of the Week | Sunday |
| Time of Event | 1333 |
| Event Time Zone | Central Daylight Time |
| Event City | Millsap |
| Event State | TEXAS |
| Event Country | -- |
| Zipcode of the event site | 76066 |
| Event Date Year | 2011 |
| Event Date Month | 8 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 324632N |
| Event Location Longitude | 0980322W |
| Event Location Airport | None |
| 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 | 1430 Central Daylight Time |
| Direction of event from weather observation facility (degrees) | 270 |
| Weather Observation Facility ID | MWL |
| Elevation of weather observation facility | 974 |
| Distance of event from weather observation facility (units?) | 5 |
| Time Zone of the weather observation | CDT |
| Lighting Conditions | Day |
| Lowest Ceiling Height | -- |
| Lowest Non-Ceiling Height | 8000 |
| 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) | 37 |
| Dew Point at event time (in degress fahrenheit) | 24 |
| Wind Direction (degrees magnetic) | 150 |
| Variable Wind Indicator | Wind direction could be determined |
| Wind Speed (knots) | 10 |
| Wind Velocity Indicator | -- |
| Wind Gust Indicator | Not Gusting |
| Wind Gust (knots) | -- |
| Altimeter Setting at event time (in. Hg) | 29.88 |
| 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) | 30642 |
| NTSB Notification Source | -- |
| NTSB Notification Date | -- |
| NTSB Notification Time | -- |
| Fiche Number and/or location -used to find docket information | -- |
| Date of most recent change to record | Dec 6 2012 8:37AM |
| User who most recently changed record | johb |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | -- |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N7698W |
| NTSB Number | CEN11LA555 |
| Missing Aircraft Indicator | -- |
| Federal Aviation Reg. Part | Part 91: General Aviation |
| Type of Flight Plan filed | Unknown |
| Flight plan Was Activated? | -- |
| Damage | Substantial |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | PIPER |
| Aircraft Model | PA-28-180 |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | 28-1690 |
| Certified Max Gross Weight | 2150 |
| 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 | 4 |
| Number of Engines | 1 |
| Fixed gear or retractable gear | Fixed |
| Aircraft, Type of Last Inspection | Annual |
| Date of Last Inspection | Oct 1 2010 12:00AM |
| Airframe hours since last inspection | -- |
| Airframe Hours | 4825 |
| ELT Installed | Yes |
| ELT Activated | Yes |
| ELT Aided Location of Event Site | No |
| ELT Type | Unknown |
| Aircraft Owner Name | GEMBALSKI HERIBERT F |
| Aircraft Owner Street Address | -- |
| Aircraft Owner City | Grand Prairie |
| Aircraft Owner State | TX |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | -- |
| Operator is an individual? | Yes |
| Operator Name | Robert Wilson |
| Operator Same as Owner? | No |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | Yes |
| Operator Street Address | -- |
| Operator City | Ronoake |
| Operator State | TX |
| Operator Country | USA |
| 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 | -- |
| 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) | Personal |
| Second Pilot on Board | No |
| Departure Point Same as Event | No |
| Departure Airport Code | MWL |
| Departure City | Mineral Wells |
| Departure State | TX |
| Departure Country | USA |
| Departure Time | 1415 |
| Departure Time Zone | CDT |
| Destination Same as Local Flt | -- |
| Destination Airport Code | GPM |
| Destination City | Grand Prairie |
| Destination State | TX |
| Destination Country | USA |
| Specific Phase of Flight | -- |
| Report sent to ICAO? | -- |
| Evacuation occurred | -- |
| Date of most recent change to record | Sep 20 2012 3:53PM |
| User who most recently changed record | yeal |
| Since inspection or accident | Last Inspection |
| Event Location Runway Number and Location | N/A |
| Runway Length | -- |
| Runway Width | -- |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |