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Rollovers:
Death, Brain Damage and Quadriplegia
The
Failure and the inadequacies of
Roof "Standards"
By
Richard Alexander
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US
Federal Motor Vehicle Safety Standard 216
Roof Deformation
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The
failure of the roof of a car or truck involved in a 'roll over'
accident is the most likely cause of death or permanent injury
to the vehicle occupants.
The
roof is, without doubt, the least crashworthy part of a vehicle.
In fact, roofs are often so 'fragile' that when 'test dropped'
upside-down for a fall of 12 inches, the result is frequently
a 'total roof crush' that in a 'real life' accident is the primary
cause of death, permanent brain and spinal cord injuries.
Most
SUV rollovers occur due to "tripping".
SUVs,
because of the design constraint compromises affecting this class
of vehicle:-
(ie - the provision of sufficient ground
clearance for 'off road' use, together with suspension compromises,
balancing customer requirements for both road and 'off road' use)
frequently results in vehicles being inherently unstable under
'emergency avoidance conditions' performed on tarmac roads - and
the vehicles will often "trip" into a forward roll - when a mild
turning movement in one direction is followed by a quick correction
in the opposite direction.
The
roll that follows causes the vehicle to be tossed and to land
on its roof on the side opposite the roll. This is the primary
reason why SUV drivers and passengers are twice as likely to be
killed in a rollover than those in a standard vehicle.
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Although
all rollover death and injuries occur while vehicles are moving,
Federal Motor Vehicle Safety Standard 216, issued by the National
Highway Traffic Safety Administration [NHTSA] in 1973, mandates
a "standing" test.
Officially
called a "static" test this "safety" rule has been in place since
the 1974 model year for cars and the 1995 model year for light
trucks and vans.
The
standard provides that "a force of one and half times the empty
weight of the vehicle or 5,000 pounds, whichever is less, be slowly
loaded onto the roof over the A pillar, the front roof support
that holds the windshield in place.
Weight
is added to a steel plate approximately 3 feet wide and six feet
long that is placed at an angle over the roof line. A roof passes
even if it collapses five inches.
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Executive Summary
