The incident took place
at 10.33pm on March 23rd 2001 on a dry road traveling uphill at moderate
speed when the car was forced to swerve to avoid an on coming car
traveling on the wrong side of the road (Highway).
The author of this report arrived within minutes of the
accident and the driver reported that the rear of the car on the offside
had dropped as he swerved and when he applied the brakes the car spun
within it's own length, traveling through 225 degrees before coming to
rest having impacted with an electricity pole as it spun.
The normal procedure for this type of accident is for a
tow truck to arrive and load the vehicle on and take it away and later
an insurance assessor will value the wreck and it would be scrapped
along with the evidence of any failure in the vehicle.
The vehicle was instead delivered to a place for
inspection, the vehicle was examined and beside the extensive damage to
the body there was indeed crush damage to the displaced wheel along with
deep scoring where the wheel having become trapped under the rear
trailing arm, had acted like a sled as the car rotated, the rotation was
exacerbated by the fact this vehicle had an ABS braking system and such
a system requires all wheels to be on the vehicle to operate correctly.
Attention was then turned to the shaft it's self, close
examination revealed an initial fracture at a depth of 10mm within the
splines of the hub, there was corrosion on part of the fracture face,
indicating that the fracture had taken place over a considerable period,
the fracture had then migrated to form other cracking within the
fracture face.
It was noted that the exit marks left by the shaft on
the hub did not match the fracture face profile and it is concluded that
the final fracture was a secondary fracture and a small section of shaft
was lost in the accident. Highly magnified photographs were then take of
the fracture face, these confirmed what could be seen on visual
examination, that the fracture face exibited all the signs of fatigue
fracture and that the shaft had indeed exited in a clean manner
indicating that the bearing was the final failure as the sideload caused
by the swerving action forced the bearing to fail . |
