Individually Owned: 150,657
Corporate Owned: 137,281
Aircraft Accident/Incident Report
Washington, Georgia 30673
Tuesady, August 10, 2010 2:15 EDT
NTSB Narrative Summary Released at Completion of Accident
During the cruise portion of a positioning flight, the pilot reported a loss of engine power to air traffic controllers. He was then radar vectored towards the closest airport but was unable to reach it. The airplane impacted trees, was partially consumed by a postimpact fire, and the pilot was fatally injured. Examination of the engine's fuel servo revealed that the hub stud in the fuel servo diaphragm assembly was fractured, which would have resulted in the fuel servo being unable to properly meter fuel. Review of maintenance records revealed that an engine overhaul had been completed approximately 18 hours prior to the accident and that the fuel servo was shipped to the fuel servo manufacturer, where the unit was overhauled using the manufacturer's components.
Examination of the hub stud revealed that it fractured as a result of fatigue cracking. The most likely cause of the fatigue cracking was a lack of braze material, which should have filled the gap between the hub stud and the hub and would have supported the shoulder of the hub stud. The manufacturer's brazing process documentation indicated that a visual check would have been performed to ensure that the braze did not exceed a certain measurement over the hub or hub stud, but there was no specific indication that a check would have been made to ensure that the braze was visible at the joint edges as required by the braze process specification, nor did any of the records provided by the manufacturer indicate the quantity of braze to be used for each assembly or how it was applied.
The hub stud from the airplane and a hub stud from an exemplar assembly (from the same batch) were also found to be significantly softer than specified by the manufacturer's assembly drawing. Based on the hardness measurements, the ultimate tensile strengths of these hub studs was only about 80 percent of the expected tensile strength. Fatigue resistance of the hub stud would have correlated with the tensile strength, so the reduced hardness relative to the specification likely played some role in the rapid onset and propagation of the fatigue cracking. The reduced hardness of the hub studs indicated that the thermal history for the brazing process was either incorrectly specified or that the process was not properly controlled for this lot of assemblies.
Also indicative of the manufacturer’s poor quality control was the lack of conformance to the drawings for the hub stud from the airplane and the exemplar hub studs; these hub studs had a groove perpendicular to the axis of the stud at the termination of the threads on the hub end, which was not in the drawing, and may have increased the stress concentrations. The hub stud from the accident fractured at the midplane of this groove, at the plane of maximum stress concentration.
NTSB Probable Cause Narrative
The manufacturer's inadequate quality control and improper manufacture of the fuel servo diaphragm assembly, which resulted in fatigue cracking of the hub stud and subsequent loss of engine power due to fuel starvation.
Event Information
| Type of Event | Accident |
| Event Date | 8/10/2010 |
| Event Day of the Week | Tuesday |
| Time of Event | 215 |
| Event Time Zone | Eastern Daylight Time |
| Event City | Washington |
| Event State | GEORGIA |
| Event Country | -- |
| Zipcode of the event site | 30673 |
| Event Date Year | 2010 |
| Event Date Month | 8 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 334549N |
| Event Location Longitude | 0824655W |
| 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 | -- |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 220 Eastern Daylight Time |
| Direction of event from weather observation facility (degrees) | 225 |
| Weather Observation Facility ID | 3J7 |
| Elevation of weather observation facility | 677 |
| Distance of event from weather observation facility (units?) | 19 |
| Time Zone of the weather observation | EDT |
| Lighting Conditions | Night |
| 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) | 26 |
| Dew Point at event time (in degress fahrenheit) | 21 |
| Wind Direction (degrees magnetic) | 100 |
| Variable Wind Indicator | Wind direction could be determined |
| Wind Speed (knots) | 3 |
| Wind Velocity Indicator | -- |
| Wind Gust Indicator | Not Gusting |
| Wind Gust (knots) | -- |
| Altimeter Setting at event time (in. Hg) | 29.99 |
| Density Altitude (feet) | -- |
| Intensity of Precipitation | -- |
| METAR weather report | -- |
| Event Highest Injury | Fatal |
| On Ground, Fatal Injuries | -- |
| On Ground, Minor Injuries | -- |
| On Ground, Serious Injuries | -- |
| Injury Total Fatal | 1 |
| Injury Total Minor | -- |
| Injury Total None | -- |
| Injury Total Serious | -- |
| Injury Total All | 1 |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 29225 |
| NTSB Notification Source | FAA Southern ROC |
| NTSB Notification Date | -- |
| NTSB Notification Time | -- |
| Fiche Number and/or location -used to find docket information | -- |
| Date of most recent change to record | Nov 8 2011 12:16PM |
| User who most recently changed record | kenj |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | -- |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N220ST |
| NTSB Number | ERA10FA409 |
| Missing Aircraft Indicator | -- |
| Federal Aviation Reg. Part | Part 91: General Aviation |
| Type of Flight Plan filed | IFR |
| Flight plan Was Activated? | Yes |
| Damage | Substantial |
| Aircraft Fire | Ground |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | PIPER |
| Aircraft Model | PA-32R-301 |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | 3246220 |
| Certified Max Gross Weight | 3600 |
| 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 | 6 |
| Number of Engines | 1 |
| Fixed gear or retractable gear | Retractable |
| Aircraft, Type of Last Inspection | Annual |
| Date of Last Inspection | Jul 30 2010 12:00AM |
| Airframe hours since last inspection | -- |
| Airframe Hours | 1960 |
| ELT Installed | Yes |
| ELT Activated | Yes |
| ELT Aided Location of Event Site | Yes |
| ELT Type | Unknown |
| Aircraft Owner Name | MS Saratoga LLC |
| Aircraft Owner Street Address | -- |
| Aircraft Owner City | Mt. Pleasant |
| Aircraft Owner State | SC |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 29464 |
| Operator is an individual? | No |
| Operator Name | COASTAL AVIATION INC |
| Operator Same as Owner? | No |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | No |
| Operator Street Address | 700 Faison Drive |
| Operator City | Mt. Pleasant |
| Operator State | SC |
| Operator Country | USA |
| Operator Zip code | 29466 |
| Operator Code | O34A |
| Owner has at least one certificate | Yes - certificate holder |
| Other Operator of large aircraft? | No |
| Certified for Part 133 or 137 Operation | -- |
| Operator Certificate Number | O34A484L |
| 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 | MDQ |
| Departure City | Huntsville |
| Departure State | AL |
| Departure Country | USA |
| Departure Time | 2348 |
| Departure Time Zone | CDT |
| Destination Same as Local Flt | -- |
| Destination Airport Code | LRO |
| Destination City | Mt. Pleasant |
| Destination State | SC |
| Destination Country | USA |
| Specific Phase of Flight | -- |
| Report sent to ICAO? | -- |
| Evacuation occurred | -- |
| Date of most recent change to record | Nov 8 2011 12:16PM |
| User who most recently changed record | kenj |
| 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 | -- |