LAX93LA345

NTSB accident investigation · Cessna 172G · Avalon, CA · September 6, 1993

Accident · No injuriesLimited investigationFinal report
Date
September 6, 1993, 14:24 local (21:24 UTC)
Place
Avalon, CA
Injuries
3 uninjured
Damage
Destroyed
Phase of flight
Enroute
Aircraft
N4143LCessna 172G
Weather
Visual (VMC) · Day
Status
Completed · report June 30, 1994
Report
Approved by Office Director
FAA report
19930906033059A
Case key
28468

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

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Probable cause

the oil starvation related failure of the number 1 and 2 connecting rods due to improper torque of the crankcase through bolts at the number 2 cylinder, which allowed fretting of the bearing surfaces and the resulting closure of the oil ports. The under torque condition was due to improper installation procedures used by the aircraft owner, and, the inadequate inspection procedures utilized by the certifying repair station.

Sequence of events

NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.

Loss of engine power(partial) - mech failure/malfCruise - normal
Engine assembly,crankcase - undertorquedCause
Maintenance,installation - improperUnqualified personCause
Maintenance,inspection - inadequateCompany maintenance personnelCause
Lubricating system,oil port/passage,internal - blocked(partial)Cause
Engine assembly,connecting rod - failure,totalCause
DitchingDescent - emergency

Analysis

The aircraft was in cruise flight about 10 miles from the island when a puff of smoke emanated from the engine cowling and the engine began to run rough. The pilot stated the aircraft could not maintain altitude and he ditched in the ocean about 100 yards off shore. The engine was disassembled and the numbers one and two connecting rods were found fractured, with heat discoloration observed on the number two bearing. Heavy fretting was found on the number two bearing surface and the associated crankcase bearing journal support. The numbers three and four cam shaft journals were observed to be visibly out of round, with heavy wear noted. Examination of the engine log book and the maintenance records from the operator revealed that the cylinder base seal for the number two cylinder was replaced on May 25, 1993, about 55 hours prior to the accident. According to the records the number two cylinder base seal 'O' ring was replaced by the aircraft owner and the work signed off by an FAA Repair Station inspector.

Factual narrative

On September 6, 1993, at 1424 hours Pacific daylight time, a Cessna 172G, N4143L, ditched in the Pacific Ocean about 100 yards off shore from Avalon on Catalina Island, California. The ditching was precipitated by a partial loss of engine power. The aircraft was operated by Rick Lucia Aviation of Ramona, California, and was rented by the pilot for a cross country personal flight. Visual meteorological conditions prevailed at the time and no flight plan was filed for the operation. The aircraft incurred substantial damage. The certificated private pilot, and his two passengers were not injured. The flight originated at Ramona on the day of the mishap at 1330 hours as a personal cross country flight to Catalina Island, and return.

According to the pilot, the aircraft was in cruise flight about 10 miles from the island, when a puff of smoke emanated from the engine cowling and the engine began to run rough. The pilot stated the aircraft could not maintain altitude and he ditched in the ocean in Avalon Bay about 100 yards off shore. Boats rescued the occupants and the aircraft sank in about 30 feet of water.

After recovery, the aircraft and engine were examined by a Safety Board investigator at Long Beach, California, on September 14, 1994. During the examination, the engine was disassembled for detailed internal review.

The numbers one and two connecting rods were found fractured, with heat discoloration observed on the number two bearing. Heavy fretting was found on the number two bearing surface and the associated crankcase bearing journal support. The numbers three and four cam shaft journals were observed to be visibly out of round, with heavy wear noted.

Examination of the engine log book and the maintenance records from the operator, revealed that the cylinder base seal for the number two cylinder was replaced on May 25, 1993, about 55 hours prior to the accident. According to Cruise Air Aviation, work order 4167 and attached discrepancy sheet, the number two cylinder base seal 'O' ring was replaced by the aircraft owner and signed off by a company inspector. Cruise Air Aviation is the holder of a FAA Repair Station authorization, number LF3R655L. The referenced maintenance records and work orders are attached to this report.

Aircraft

Registration
N4143L
Reported as
Cessna 172G
Category
Airplane
Serial number
17254212
Airframe hours
3,375
Engine
Continental O-300-G, 145 horsepower, reciprocating
Damage
Destroyed
Flight
Personal · Part 91
Operator
Rick Lucia Aviation
Registered owner
Brent Sundin
Airworthiness certificate
Standard, Normal
Last inspection
Annual · May 24, 1993 · 55 hours before
Departed
L39 · Ramona, CA

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
39
Certificate
Private
Airplane ratings
Single-engine land
Instrument ratings
Airplane
Medical
Class 3, Valid Medical--no waivers/lim.
Seat
Left
Flight hours
240 total · 63 in this make and model · 177 as pilot in command · 2 in the last 90 days · 2 in the last 30 days · 2 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Visibility
30 statute miles
Lowest ceiling
None

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.

Other investigations on N4143L · 1

Matched to the same aircraft by N-number and date.