Cessna 172N N24CV

Summary

On 14 February 2010 at about 02:15 local time, a Cessna 172N registered N24CV, operated by Bowen Aviation LLC, was involved in an accident near Genoa City, Wisconsin, United States. One person was on board and one had minor injuries. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

14 February 2010 at 02:15

Classification

Accident

Location

Genoa City, Wisconsin, United States

Coordinates

42.5578, -88.3156

Aircraft

Cessna 172N

Registration

N24CV

Category

Airplane

Engines

1

Operator

Bowen Aviation LLC

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Aurora → Green Bay

Aircraft damage

Substantial

Weather

VMC

Light

Night

NTSB number

CEN10LA123

1 person had minor injuries.

A total loss of engine power due to the failure of the bolts that held in place the connecting rods to the engine's No. 3 and No. 4 cylinders as a result of the engine overhaul facility's improper installation of the bolts during a recent overhaul.

Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.

Read the full NTSB narrative

The pilot stated that during cruise flight he heard a “loud metallic clicking” sound, followed by a “bang” and a vibration. A few seconds later there was another “bang” and the propeller stopped rotating. He subsequently executed a forced landing to a corn field, where the airplane sustained damage to the firewall, nose landing gear, and wings. A postaccident examination on the engine revealed that the No. 3 and No. 4 engine connecting rod bolts had failed. Metallurgical examination determined that the bolts failed as a result of overstress fractures. No evidence of a fatigue fracture was observed. The teardown examination of the engine revealed that the nuts installed on the No. 1 and No. 2 connecting rod bolts were not tightened to the engine manufacturer’s specifications. Maintenance records indicated that the engine had been overhauled and the airplane returned to service about two weeks prior to the accident. At the time of the accident, the engine had been operated about 68 hours since the overhaul. The lack of proper torque on the intact rod bolts/nuts and the overstress failure of the remaining bolts indicates that the connecting rods were not installed properly during the overhaul procedure.

Quoted verbatim from the NTSB record.