CEN09LA209

NTSB accident investigation · Beech B24R · Bellefontaine, OH · March 15, 2009

Accident · No injuriesLimited investigationFinal report
Date
March 15, 2009, 15:00 local (19:00 UTC)
Place
Bellefontaine, OH
Injuries
2 uninjured
Damage
Substantial damage
Phase of flight
Enroute
Aircraft
N9348SBeech B24R
Defining event
Enroute-cruise: Loss of engine power (total)
Weather
Visual (VMC) · Day
Status
Completed · report July 14, 2009
Report
Approved by Office Director
NTSB office
Central Region
Parties
Federal Aviation Administration - Columbus FSDO
Case key
73494

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 inadequate torque of the Number 3 cylinder rod bolts by maintenance personnel, which resulted in a failure of the connecting rod and a total loss of engine power.

Findings · 4

NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.

Engine (reciprocating): recip engine power sectionAircraft › Aircraft power plant · Incorrect service/maintenanceBeech B24R: 1 caseAll aircraft: 233 casesProbable cause
Maintenance: installationPersonnel issues › Task performance · Maintenance personnelBeech B24R: 1 caseAll aircraft: 371 casesProbable cause
Object/animal/substance: fence/fence postEnvironmental issues › Physical environment · Contributed to outcomeBeech B24R: 2 casesAll aircraft: 313 cases

Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.

Analysis

During cruise flight the pilot noticed abnormal engine noises and a partial loss of engine oil pressure. He immediately diverted to the nearest airport, but during the turn to base leg the engine oil pressure dropped to zero pounds per square inch and the engine seized. The airplane was not in a position to reach the runway threshold or to clear the airport perimeter fence. During the landing rollout the airplane impacted the airport perimeter fence, damaging both wings and the nose landing gear. An engine teardown examination revealed that the Number 3 cylinder connecting rod assembly had separated from its corresponding crankshaft journal. The journal surface was blue in color, consistent with exposure to excessive heat and lack of lubricant. The oil suction screen was obstructed with bearing material. The Number 3 cylinder connecting rod cap was found jammed beneath the counterbalance weight. One of the two connecting rod stretch bolts remained intact. The corresponding nut was found finger tight. The measured torque for the Number 2 cylinder connecting rod bolts were significantly less than the manufacturer's specification. The engine had accumulated a total of 3,799 hours since new and 492.7 hours since its last overhaul in 1999. The engine was last inspected 23.9 hours before the accident occurred.

Factual narrative

On March 15, 2009, at 1500 eastern daylight time (edt), a Beech B24R (Sierra), N9348S, owned and piloted by a private pilot, was substantially damaged during a forced landing following an en route loss of engine power near Bellefontaine, Ohio. Visual meteorological conditions prevailed at the time of the accident. The personal flight was operating under the provisions of 14 Code of Federal Regulations (CFR) Part 91 without a flight plan. The pilot and his passenger were not injured. The flight departed Grimes Field Airport (I74), near Urbana, Ohio, at 1445 edt and was en route to Bluffton Airport (5G7), near Bluffton, Ohio. According to the pilot, the airplane was in cruise flight when he noticed abnormal engine noises and a partial loss of engine oil pressure. He immediately diverted to the nearest airport, Bellefontaine Regional Airport (KEDJ), and entered downwind for runway 7 (4,999 feet by 100 feet, asphalt). During the turn to base leg, the engine oil pressure dropped to zero pounds per square inch and the engine seized. He established best glide speed and continued the turn onto final approach. The pilot reported that the airplane was not in a position to reach the runway threshold, or to clear the airport perimeter fence. He lowered the landing gear and selected full flaps prior to landing in the grass area outside of the airport perimeter fence. During landing rollout the airplane impacted the airport perimeter fence, damaging both wings and the nose landing gear. An engine teardown examination revealed that the number 3 cylinder connecting rod assembly had separated from its corresponding crankshaft journal. The crankshaft journal surface was blue in color, consistent with exposure to excessive heat and lack of lubricant. The oil suction screen was obstructed with bearing material. The number 3 cylinder connecting rod cap was found jammed beneath the counterbalance weight. One of the two connecting rod stretch bolts remained intact. The corresponding nut was found finger tight. The measured torque for the upper and lower stretch bolts on the number 2 cylinder connecting rod was 15 foot-pounds (ft-lbs) and 6 ft-lbs, respectively. The manufacturer specified torque value was 40 ft-lbs. The Lycoming IO-360-A1B6 engine, serial number L-13455-51A, had accumulated 492.7 hours since its last overhaul in September 1999 following a propeller strike.

Aircraft

Registration
N9348S
Reported as
Beech B24R
Category
Airplane
Serial number
MC-350
Airframe hours
3,799
Engine
Lycoming IO-360-A1B6, 200 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Airworthiness certificate
Standard, Normal
Last inspection
Annual · April 25, 2008
Departed
I74 · Urbana, OH
Destination
5G7 · Bluffton, OH
Airport
KEDJ · Bellefontaine Regional Airport

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
47
Injuries
None
Certificate
Private
Airplane ratings
Single-engine land
Medical
Class 3, With waivers/limitations
Last flight review
July 21, 2007
Seat
Left
Flight hours
587 total · 274 in this make and model · 587 as pilot in command · 2 in the last 90 days · 2 in the last 30 days · 1 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
80° at 10 knots
Visibility
10 statute miles
Lowest ceiling
None
Temperature
57 °F, dew point 27 °F
Altimeter
30.09 inHg
Observed at
KOAH, 22 nm away