NTSB Says Airplane Had Likely Suffered A 'Previously
Undocumented Propeller Strike'
That Lancaire which went down in March, 2010 in Hilton Head,
fatally injuring a man jogging on the beach during the emergency
landing, turns out to have likely suffered damage to its propeller
and crankshaft sometime before the accident, according to the
NTSB's probable cause report.
NTSB Identification: ERA10LA175
14 CFR Part 91: General Aviation
Accident occurred Monday, March 15, 2010 in Hilton Head Island,
SC
Probable Cause Approval Date: 06/27/2011
Aircraft: SMITH EDWARD I LANCAIR IV-P, registration: N9JE
Injuries: 1 Fatal, 2 Uninjured.
According to the NTSB's probable cause report, the pilot stated
that while in cruise flight he observed the instrument panel begin
to vibrate heavily and oil begin to cover the wind screen before
hearing a loud "bang." The engine then lost power as oil continued
to obscure the wind screen. The pilot had no forward visibility and
could not maintain the airplane's altitude. He elected to make an
emergency landing on a nearby beach and during the landing the
airplane struck and killed a pedestrian. Examination of the
airplane revealed that the propeller assembly separated from the
crankshaft and was missing. The propeller assembly and propeller
flange were not recovered.
An examination by the NTSB Materials Laboratory of the
crankshaft revealed that the aft face of the fracture contained
crack arrest marks. The fracture of the crankshaft was caused by
multiple-origin fatigue cracks that emanated at the aft relief
radius for the propeller flange. The records for this engine and
airplane do not show an entry of a propeller strike. However,
multiple-origin fatigue cracks that extend nearly 50% around the
circumference of the aft relief radius for the propeller flange
suggest that the propeller had struck an object prior to fracture
of the crankshaft. In the absence of material anomalies, the
fatigue cracking appears likely to have been caused by external
impact stress, such as a propeller strike.
The National Transportation Safety Board determines the probable
cause(s) of this accident to be a loss of engine power due to the
failure of the crankshaft as a result of a previously undocumented
propeller strike.
The engine was disassembled and inspected by a Teledyne
Continental Motors (TCM) investigator with FAA oversight. No
anomalies were noted within the engine assembly. TCM found evidence
of fatigue cracking on the fracture face of the crankshaft. At the
request of the NTSB Materials Laboratory, TCM made a cut through
the main journal portion in an area located approximately two
inches aft of the fracture. The two-inch segment was shipped to the
NTSB Materials Laboratory for further examination.
An examination by the NTSB Materials Laboratory of the two-inch
segment of the crankshaft revealed that the aft face of the
fracture contained crack arrest marks. The aft relief radius for
the propeller flange contained no evidence of mechanical damage,
such as gouge marks. The fatigue crack propagated through the full
thickness of the wall of the crankshaft, and extended around
approximately 50 percent of the crankshaft circumference. The
remaining portion of the fracture face contained a rough texture
consistent with overstress separation.
A review of the engine logbooks dating back to September 13,
1996, revealed that the engine was installed on a Piper Malibu,
N70DL, serial number 46-8608001, and did not reveal any anomalies
that would have been contributing to the fatigue crack. The last
entry dated July 28, 1998, at a Hobbs time of 1806.6 hours for
aircraft N70DL revealed that an oil and filter change was
conducted. There were no entries for this engine for the next four
years. A review of the propeller and aircraft logbook entries also
did not reveal any anomalies that would have contributed to the
fatigue crack. On May 31, 2002, the records revealed that the
engine was disassembled, cleaned, and inspected to check for
corrosion and overall condition. New exhaust guides were installed;
the valves and seats were ground, the cylinders were oversized and
new piston rings were installed. The engine was reassembled using
parts that were supplied on a work order in accordance with data
approved by or acceptable to the FAA. The engine was run in a test
cell and returned to service. The engine was then stored for
approximately seven years. After the engine was purchased by the
new owner, a logbook entry revealed that the engine was converted
from a model TSIO-550-C to a model TSIO-550-B in accordance with
Continental Service Bulletin M75-6, REV. 1, and dated 6/4/1975. The
conversion was completed by the owner/mechanic on January 15, 2009,
installed and returned to service after a 100-hour inspection. The
engine accumulated 99 hours since it was converted and installed on
the current airplane.
In a telephone conversation with the previous owner of the
engine, he said that he originally intended to install the engine
in an airplane that he was building. The engine was sent to a
service center to be inspected, and repaired as necessary. He had
no knowledge of any damage to the engine during his ownership. The
engine was never installed on his airplane or used after the
service.