FLIGHT FINDINGSAVIATION OCCURRENCE MAP
Back to map

ERA10FA409 · Piper PA-32R-301

10 Aug 2010 · Washington, GA, United States

Coastal Aviation Piper PA-32R-301 · Accident: loss of engine power (total) en route

From Madison County Executive Airport-Tom Sharp Jr Field (MDQ) to Mount Pleasant Regional Airport Faison Field (LRO)

Report a problem

Event

NTSB case
ERA10FA409
Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
Accident
InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
Completed
API-reported fatalities
1 · all aircraft and ground
Ground fatalities
Unknown
OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
General aviation
WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
Visual Meteorological Cond

Piper PA-32R-301

Aircraft type
Piper PA-32
Category
Airplane
RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
N220ST
Onboard fatalities
Unknown
Route
From Madison County Executive Airport-Tom Sharp Jr Field (MDQ), Huntsville, ALTo Mount Pleasant Regional Airport Faison Field (LRO), Mt. Pleasant, SC
Aircraft age
Not recorded
Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
Part 91: General Aviation
Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
En route · cruise
Defining eventThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
Loss of engine power (total)
DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
Substantial

Cause areas

  • Aircraft › Aircraft power plant
  • Organizational issues › Development

Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.

NTSB narrative

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.

Probable cause

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.

Verbatim NTSB analysis and probable cause from the NTSB dataset

Sources

NTSB record ERA10FA409
Event ID
20100810X73301
Case number
ERA10FA409
Dataset
full-current
Source SHA-256
5cf380f0061817c0331a6b2d8cc7e0ee3a79bea469a1001dc5c10e56f35f5ab3
Source notes (4)
  • Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
  • Filled from the NTSB case API where the bulk record had no value: investigation status. Values present in the bulk record are kept.
  • The date is the local date, which is the same as the UTC date the NTSB stores.
  • API snapshot SHA-256: 43150c48a011c07688a6783efdcd5a6c98f1dae6d41b08c973d28052805a05b7; retrieved 2026-09-13T20:59:46.896Z.