8
OF 9 MIDSIZE SUVs EARN TOP RATING OF GOOD
NEW
40 MPH CRASH TEST RESULTS FROM IIHS
In
frontal offset crash tests conducted recently by the Insurance Institute for Highway
Safety, eight new or redesigned midsize SUVs earned ratings of good, and one is
acceptable. Three luxury models (Lexus RX 330, Infiniti FX, and Cadillac SRX)
earned good ratings overall and the added designation of "best pick."
Five other SUVs (Toyota 4Runner, Nissan Murano, Chrysler Pacifica, Honda Pilot,
and Mitsubishi Endeavor) also earned good ratings, and all but the Endeavor are
best picks. The Kia Sorento is rated acceptable.
Vehicle
ratings reflect performance in 40 mph frontal offset crash tests into a deformable
barrier. Based on the results, the Institute evaluates the crashworthiness of
passenger vehicles, assigning each vehicle a rating from good to poor overall.
If a vehicle earns a good rating, it means that in a real-world crash of similar
severity a belted driver would be likely to walk away without serious injuries.
"These
results demonstrate the effectiveness of the Institute's frontal crash test program
in bringing about improvements in vehicle designs," said Adrian Lund, the
Institute's chief operating officer. "When the Institute first tested midsize
SUVs in 1996, none was rated good. Now there are 16 current midsize SUV designs
rated good." But Lund notes that "7 still are rated marginal or poor."
Toyota
4Runner is best performer: The redesigned 4Runner improved compared with the previous-generation
model that was rated acceptable when the Institute tested it in 1996.
"The
previous model had some intrusion into the footwell area, and the steering wheel
moved upward too much during the crash, compromising the performance of the restraint
system," Lund said. "In contrast, the new 4Runner is a good performer
across the board with minimal intrusion into the passenger compartment, a steering
column that doesn't move much, and low injury measures on the dummy. It's a good
performer and a best pick."
Kia
Sorento is only acceptable: While the structure of the Sorento held up well, the
restraint system didn't do a good job of controlling the dummy's movement during
the crash.
"Kia
has room for improvement with the Sorento," Lund said. "The dummy's
head hit the steering wheel through the airbag and also struck the door frame
on rebound. Both hits were hard. Plus the driver's seat tipped toward the door,
which compromises restraint system performance."
Honda
and Infiniti are tested twice: In the first tests of the Pilot and the FX, the
front airbags deployed late. As a result, the dummies recorded high head accelerations.
"The
engineers at Honda and Nissan recognized that their airbag systems needed to be
improved. They made changes to the
software that controls airbag firing, and we
retested both models. In the second tests, the airbags fired much earlier and
the high head accelerations were eliminated. With the change, the Pilot and FX
are good performers and best picks," Lund said. Both companies are conducting
recalls to modify the airbag software on earlier models.
Structural
design is key to good performance: The Institute's frontal offset test into a
deformable barrier is especially demanding of vehicle structure. The driver side
hits the barrier, so a relatively small area of the vehicle's front-end structuremust manage the crash energy. This means intrusion into the occupant compartment
is more likely to occur than in a full-width test.
"Good
structural design is the key to good performance in the offset tests," Lund
says. "If a vehicle's front-end structure absorbs and manages the crash energy
so the occupant compartment remains largely intact, with little or no intrusion
into the driver's space, then the dummy's movement can be controlled, and injury
measures are likely to be low. In contrast, poor structural design means greater
likelihood of poor control ofthe dummy and high injury measures."
Institute
and government crash tests complement each other: The Institute's crashworthiness
evaluations are based on results of frontal offset crash tests at 40 mph. Each
vehicle's overall evaluation is based on three aspects of performance — measurements
of occupant compartment intrusion, injury measures from a Hybrid III dummy positioned
in the driver seat, and analysis of slow-motion film to assess how well the restraint
system controlled dummy movement during the test.
The
federal government has been testing new passenger vehiclesin 35 mph full-front
crash tests since 1978. This New Car Assessment Program has been a major contributor
to crashworthiness improvements — in particular, improved restraint systems in
new passenger vehicles. The Institute's offset tests, conducted since 1995, involve
40 percent of a vehicle's front end hitting a deformable barrier at 40 mph. This
test complements the federal test involving the full width of the front end hitting
a rigid barrier. Both tests are contributing to improvements in crashworthiness
— in particular improved crumple zones and safety cages.
The
same 40 mph offset crash test is used to evaluate new cars by the European Union
in cooperation with motor clubs, by an Australian consortium of state governments
and motor clubs, and by a government-affiliated organization in Japan.
RELATED
LINK: More
Information from IIHS
(Source: IIHS)
