OKLAHOMA
CITY — Alabama's highest court says a lawsuit involving a deadly
Oklahoma airplane crash is time-barred and must be dismissed.
Friday's
ruling by the Alabama Supreme Court involves the July 24, 2005, crash
of a twin-engine airplane in Ada that killed three members of a
prominent Oklahoma family.
Killed
were Harland Brent Stonecipher, a pilot for a company then known as
Pre-Paid Legal Services, Inc.; his wife, Tina Lynn Stonecipher, and
their 11-year-old daughter Nicole Ann Stonecipher. Harland Stonecipher
was the son of Pre-Paid's founder, also named Harland Stonecipher. The
company is now known as LegalShield.
Litigation
involving the crash has been handled in Alabama, and a lawsuit filed in
2007 was settled. But the Supreme Court says another filed in 2011 is
barred by that state's two-year statute of limitations.
NTSB Identification: DFW05FA188.
The docket is stored in the Docket Management System (DMS). Please contact Records Management Division
Accident occurred Sunday, July 24, 2005 in Ada, OK
Probable Cause Approval Date: 03/26/2007
Aircraft: Cessna 310Q, registration: N1971W
Injuries: 3 Fatal.
NTSB
investigators either traveled in support of this investigation or
conducted a significant amount of investigative work without any travel,
and used data obtained from various sources to prepare this aircraft
accident report.
The 1,500-hour airline transport rated pilot had
just departed a 6,305-foot-long runway when, based on a viewing of
security camera footage, a puff of white smoke exiting the back of the
right engine shortly after the airplane became airborne. The airplane
then began a right turn and flew on a westerly heading at a low altitude
before it disappeared behind a tree line. A witness saw the airplane as
it was in a right turn toward the north. He thought the airplane was
going to land on a closed highway, but the nose of the airplane dropped
and the airplane cartwheeled on the grass median west of the road.
Examination of the right engine revealed that the crankshaft gear had
failed due to a fatigue fracture in one of the teeth. The fatigue
emanated from the pressure face of the tooth and intersected another
crack emanating from the non-pressure face of the tooth, thereby
producing separation of the tooth from the rim. Near the origin,
post-fracture damage prevented the ability to determine if the crack
initiated in fatigue or if a crack propagated in overstress through the
case and then continued propagating through the core in fatigue. Upon
completion of the materials examination it was evident that the
microstructure of the gear was inadequate and more research into the
manufacturing process was required. A review of manufacturing records
indicated that approximately 2,400 crankshaft gears were made from the
same batch of material as the accident gears, and were heat-treated in
two groups. A review of the heat treatment records confirmed that
furnace temperatures during the hardening step in each heat-treating
process were not high enough to fully austenitize the material.
Furthermore, the quantity and orientation of gears loaded in the furnace
were greater when compared to other jobs completed for TCM. In
addition, initial data from a test load similar to that used in the
heat-treating process from the accident serial number gear, indicated
that under these conditions, the gears might not have been fully
equilibrated at temperature during the hardening step. As a result, TCM
manufactured several other gears at different hardnesses and conducted
failure testing to see if they could reproduce a similar failure. Even
though some of the hardness levels were well below TCM standards, they
were unable to produce a similar failure. In addition, there was
evidence to suggest that the gear teeth may have been exposed to an
excessive load at some point during its operation. The cause of the gear
tooth failure could not be determined.
The National Transportation Safety Board determines the probable cause(s) of this accident to be:
The
loss of engine power as a result of a fatigue fracture in one of the
crankshaft gear teeth for undetermined reasons. Also causal was the
pilot's failure to maintain control of the twin-engine airplane after
the power loss, which resulted in an inadvertent stall and subsequent
collision with terrain.
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