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From the Battlefield to the Soccer Field
Tracking the Fallout from the "Arms Race"
A Wooly Mammoth for Teenage Eyes
The Evolution of the SUV: A Pictorial Timeline
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Scapegoat Utility Vehicle?
Light Trucks Dodge the Spotlight
On February 15, 2005, scientist Tom Wenzel
with the Lawrence Berkeley National Laboratory gave a presentation at
the UC Berkeley Traffic Safety seminar entitled, “Are SUVs Really Safer
than Cars?” Although Wenzel's analysis added significantly to the
ongoing debate about whether SUVs' large presence in the mix of vehicles
on the nation's roads creates a net step back or a forward in terms of
traffic safety, it also found another element in the safety mix that has
been largely overlooked: the danger from the ubiquitous pickup truck.
Using data from the National Highway Traffic Safety Administration’s most authoritative accident database, the Fatal Accident Reporting System (FARS), Wenzel found that the real menace posed by SUVs' design was to other drivers. Taking his analysis one step further, and looking at combined risk—the risk that a vehicle poses both for its driver and for drivers of vehicles with which it crashes—"most cars are safer than the average SUV, while pickup trucks are much less safe than all other vehicle types,” Wenzel states in his report, also titled "Are SUVs Really Safer than Cars?"
Obscured amid all the questions about the safety of the SUV has been the performance of its older, more simply engineered sibling, the pickup truck. Its market share has increased from 16 percent in the late 70s to a quarter of all annual U.S. vehicle sales by 2000, and its presence on the road raises the same "incompatibility" issues that plague SUVs in collisions. Fundamental truck design—which until recently was shared by nearly all SUVs and pickups—jeopardizes car occupants to such a great degree that it rivals the damage done if people fail to wear seat belts, the single most effective safety strategy in terms of reducing deaths and fatalities. And while SUV designs have begun to be adjusted so that they are less lethal to passengers in smaller vehicles when they collide, the pickup truck has remained effectively unchanged for 50 years.
Much has been made of the rise of the SUV to its present dominance of the consumer market from its roots as a battlefield icon of World War II. But hidden in that story is the success of the truck as well, a uniquely American anomaly with an aggressive, incompatible design that has benefited from favorable tax breaks and import tariffs, as well as numerous exemptions from 30 years of fuel efficiency and emissions standards.
How the Pickup Got Its Start
In the 1970s, at the beginning of a regulatory period that would reshape the highway landscape, pickup trucks were a small portion of the U.S. vehicle fleet. Their uses were primarily commercial, and their construction was based on a rugged, simple, then-20-year-old design that continues to this day. Two steel bars—which together form the spine of the vehicle—run parallel from front to back. Cross bars are welded to them to form a steel ladder onto which the rest of the components are bolted.
The stiff, reinforced steel latticework provides the strength and rigidity needed for hauling heavy cargo on uneven surfaces, sometimes while towing heavy loads—all common tasks in commercial applications.
When the fuel shortages of the 1970s generated the Corporate Average Fuel Economy (CAFÉ) standards and the Clean Air Act, both of which mandated costly new changes to vehicle design and technology, vehicle manufacturers managed to get light trucks a reprieve. Rather than the 27.5 miles per gallon most vehicles were required to achieve by 1985, trucks would only need to get 20.5. They enjoyed similar breaks for pollution emissions under the Clean Air Act.
The argument for the less stringent
treatment hinged on protecting commercial enterprises from undue costs
imposed by government efforts to encourage fuel conservation and reduce
emissions. In reality, overall consumption increased, and trucks became
more affordable than cars (because of the added costs of compliance with
the new laws). Furthermore, pickup trucks and their new SUV siblings in
the "light truck" family enjoyed market protection in the form of import
tariffs that were as high as 25 percent until the end of the century,
effectively giving American manufacturers an edge over foreign
competitors. American manufacturers played on their advantage, spending
billions selling recreational consumers on the pickup's commanding view,
ability to carry and tow equipment and the possibility of going
off-road.
In the 1980s, pickup trucks and vans comprised roughly 18 percent of annual vehicle sales (while SUVs were just starting to register sales in any notable numbers). Over the next 20 years, pickup trucks would steadily gain market share, but with none of the attention given to SUVs, which went from virtually no market share in the early 80s to 20 percent of all vehicles sold in 1999. The rise of these two classes of vehicle came at the expense of cars, whose market share declined in the same period.
Industry statistics cited in Time magazine show that by 1999 SUVs, plus pickups and vans (another vehicle type that enjoyed a rapid rise in popularity) accounted for nearly 50 percent of the year’s sales. Pickup trucks alone had a 20 percent share. In the next few years, pickups vied with SUVs for the top spot in consumer preferences for the light truck category, according to statistics compiled by industry research house, Polk Automotive Intelligence. Among males, pickups and SUVs were the top choice. In the key 34-55 Baby Boomer demographic group, it was true as well, with SUVs edging out pickups with a 19 percent share of sales in 2000. With SUVs capturing the highest percentage (23.9 percent) of new market sales among females of all ages in January of 2002, the combined models based on the light truck design—SUVs, pickups and vans—had eclipsed midsize cars as the preferred car of women for the first time ever. (Minivans are categorized as light trucks in emissions regulations due to their use of a truck body, albeit on a lowered, more car-compatible frame.)
The shift is reflected in the operating fleet. In 2004, Polk predicted that “during the next five years we expect light truck vehicles in operation (VIO) to grow by over 13 percent and passenger car VIO to fall by nearly 19 percent.
"In 2003, passenger cars comprised 60 percent of vehicles in operation, and light trucks were 40 percent of vehicles in operation." Polk projects, that "by 2008 the percentage of cars will decrease to 54.7 while light trucks increase to 45.3.”
Clashing Designs on the Highway
The light truck designs had come to dominate the market, cutting into car sales, and safety groups began to notice the fallout from the resulting new incompatibility in the fleet as early as 1993. That year, German safety researchers staged an experimental crash between a 2,400-pound VW Golf and a Nissan SUV that was twice as heavy, which produced injuries on the crash dummy in the Golf that were literally off the scale in terms of fatal force.
In 1996 U.S. researchers William T. Hollowell and Hampton C. Gabler did a statistical analysis of crash data for NHTSA that showed that 20-year-old NHTSA crash test methods weren’t reflecting the new dynamics between these less compatible vehicles and the conventional passenger cars in the fleet.
"The effect of this tremendous degree of fleet incompatibility is not measured directly by frontal-barrier crash tests and will be the focus of future research," they concluded.
“American car makers have largely ignored how the design of a vehicle may affect other vehicles in a crash, contending that it is weight difference, and not design, that determines who lives and who dies in crashes,” notes Neil Bradsher, longtime automotive writer for the New York Times and author of the 2002 book, High and Mighty – SUVs: the World’s Most Dangerous Vehicles and How They Got That Way. “Yet,” Bradsher continues, “research in Britain has found—and the top safety official for the American auto manufacturers' trade group agrees—that sport utility vehicles and pickups are particularly deadly when they hit a car in the side because they ride higher off the ground and are more likely to strike the occupant of the car in the head and chest. Crashes with light trucks, particularly pickups and sport utility vehicles, are especially deadly for people riding in the small, fuel-efficient cars that have been produced over the last quarter-century in an attempt to reduce gasoline consumption and pollution. And pickups and sport utility vehicles pose an even bigger threat for the extremely fuel-efficient, 2,000-pound family cars that auto makers say they will build early in the next century.”
Wenzel elaborated on the statistical reality of our fleet’s increasing incompatibility in his seminar. Using FARS data, Wenzel plotted a graph of the combined risk of 40 types of cars, SUVs and pickup trucks.
Wenzel defined “risk” as driver deaths per year per million vehicles registered. He defined “risk to other drivers” as driver deaths in other vehicles involved in a collision with a specified vehicle per year per million vehicles registered. The data yielded a graph where the X axis indicates risk to drivers of the vehicles and Y axis indicates the risk to “other drivers” as measured by the same metric. The combined risk is shown where the two intersect.
The graph yields three distinct zones that both reinforce and defy received wisdom. Luxury cars and midsize cars occupy the bottom left corner of the graph, meaning that they had the safest combined risk for their drivers and the drivers of the cars that they crashed into. In the center were SUVs, moderately dangerous to themselves and others, and out in the far top right were the pickup trucks, menacing both their drivers and the drivers in the other cars.
On average, pickup trucks killed 100 of their drivers and 100 other drivers per million vehicles registered each year. By comparison, SUVs killed 75 of their drivers and 50 drivers of other cars. Down in the safe corner, luxury cars killed 27 of their drivers and 25 drivers with whom they collided. Wenzel controlled statistically for who was more likely to be driving the vehicles like young men in sports cars and Baby Boomer women in minivans. He used drivers because that eliminates potentially confounding factors like multi-passenger vans having their results skewed simply because more people tend to ride in them at any given time.
“Pickup trucks, as driven, are riskier than any other major type of vehicle. The risk to drivers of the average pickup is higher than that for minivans, SUVs, and large and midsize cars, although it is not significantly different from that of the average compact and subcompact car," Wenzel states.
"The combined risk to drivers of pickups and the vehicles they crash into is much higher than that for other vehicle types...Light trucks, especially pickups and to a lesser extent SUVs are responsible for the deaths of many people in other vehicles." This result supports earlier informal surveys of police regarding the outcomes of two-vehicle crashes. He found that there are twice as many deaths in car-to-pickup crashes as in car-to-car crashes and 1.8 as many deaths in SUV-car crashes as in car-to-car.
Wenzel explained how his examination of the data was different from previous ones, including work done by the Insurance Institute for Highway Safety. “Our analysis differs from the Institute’s in two important ways. First we examine risks not only to drivers of vehicles of a particular type, but also to drivers of vehicles that crash with that vehicle type. Second we limit our study to recent models having sold enough vehicles to permit statistical analysis. By studying risks associated with vehicle models built between 1995 and 1999, we focus on vehicles with up to date safety designs and restraint technologies.”
Wenzel also broke the data down into finer categories. “The focus of most statistical analysis of this issue has been on averages, especially the average weight of cars and light trucks. In our opinion, the issue is too complex for such broad averaging. The risks depends on vehicle type (for example, car class, van, SUV, or pickup truck) and model, as well as who drives the vehicle, and where, when and how much it is driven,” Wenzel says.
Wenzel pointed out that “total societal risk would include occupants other than drivers, others outside of vehicles, and injuries as well as fatals, which is beyond the scope of this particular analysis.
“It’s extremely difficult to determine inherent safety of a vehicle type or model because of the difficulty in separating the contributions of driver characteristics and behavior from the contribution of vehicle design. For example some car models may attract relatively aggressive drivers, who increase the fatalities in the model, independent of its design."
How Design Matters
Still, Wenzel suggests that “a substantial part of the risks light trucks impose on other drivers is associated with the design of light trucks.”
Recent data from the Insurance Institute of Highway Safety meshes with Wenzel’s claims of incompatibility due to inherent design characteristics, independent of driver attributes. A 1998 study by the Institute found that when a car collides with an SUV or pickup, the car’s occupants are about four times more likely to die than the people in the bigger, heavier vehicle.
Not surprisingly, the Institute found that vehicle occupants at one extreme of the compatibility issue—small-car occupants in collisions, and those in small to midsize SUVs in rollovers—suffer the highest fatalities. Vehicles with the lowest rates of driver deaths included a broad array from foreign companies like Mercedes, Toyota, Volkswagen, Honda and Lexus (though two American makers, Cadillac and Mercury, were represented on the list). Those with highest rates of fatalities per million vehicles registered annually were more than triple the average, which was 87 yearly deaths per million vehicles registered. These referred to overal deaths. In terms of single vehicle rollover crashes, 11 vehicles had more than 75 driver deaths per million registered vehicles, and they were all pickups or SUVs.
Further research pointed to the actual light truck design flaws that contributed to occupant and extra-vehicular deaths. Namely: height and speed. “New research in Britain suggests that height differences could be particularly important when sport utility vehicles and pickups hit cars in the side. Side impacts account for nearly a third of all car-occupant deaths each year. Yet Federal tests in the United States only measure a car or light truck's ability to withstand being hit in the side by the equivalent of a midsize sedan,” Bradsher reported in 1997.
“The 3,015-pound sled used for the side-impact test has a bumper with a lower edge only 13 inches off the ground and a top edge 21 inches high. The lower edge of the test sled is designed to reflect the fact that most vehicles brake before hitting a car in the side, so their bumpers are a little lower than usual. But the low edge also means that the test sled hits not only the car door, which is relatively weak, but also the side of the car's underbody, its sturdiest part, typically 15 inches off the ground.”
Barry Felrice, the top safety official at the American Automobile Manufacturers Association, told Bradsher in 1997 that because sport utility vehicles and pickups ride high, when they have side-impact collisions with cars, the damage to people in the cars tends to be more severe. "You're likely to be hit in the parts of the body that are more prone to injury," he tells Bradsher, "like the chest or the head."
When the vehicle does ride over the side
doors and hoods of lower cars, the relatively old-fashioned frame turns
into a weapon inflicting blunt force trauma. The two pieces of steel
that form the light truck’s spine run parallel underneath the vehicle
and extrude from the front like tines of a fork, prepared to ride up
over sedan doors, pierce the cabins and inflict trauma on passengers.
MY02 Dodge Ram 150 pickup truck
Pickups also roll over more easily, so that they generally behave like SUVs in most key respects.
“Pound for pound [i.e. controlling for weight], across all vehicle types, cars almost always have lower death rates than either pickups or SUVs. This generally is because the SUVs and pickups have much higher rates of death in single-vehicle rollover crashes,” said Institute executive Adrian Lund.
But unlike SUVs, pickup designs aren’t really changing in response to these shortcomings. SUVs and trucks may have both begun with two steel rails, cross braced and fitted with parts, but SUVs are evolving different designs along safety lines. New technologies are also important ingredients in this evolution to safer SUVs. Electronic stabilization systems, for example, are already showing a statistically significant effect.
“Not all midsize SUVs had high death rates in single vehicle rollovers,” the Insurance Institute reports in 2005. “The Lexus RX 300, Toyota 4Runner, Nissan Pathfinder, and Acura MDX had 6 or fewer rollover deaths per million vehicle years. Both the RX 300 and 4Runner are equipped with electronic stability control, which has been shown to significantly reduce the risk of fatal single-vehicle crashes including rollovers.” The Institute added, “not one driver death occurred in a rollover of the RX 300 or 4WD Toyota RAV4.”
Many new SUV models are using designs that depart from the rigid steel frame approach and weigh less. Their front ends are being reconfigured to lower heights to match sedans and are being padded with shock absorbing metal. Even their roofs are set to become stronger.
A development with promise from a safety standpoint is the growth in the so-called "crossover SUVs,” marketed to exploit some of the allure of the high-capacity rugged vehicles, but weighing hundreds of pounds less and utilizing unit-body designs like those that normally make up the skeleton of cars. The unit body looks like a steel cage, which the parts are then soldered and bolted onto. This cage will flex and crumple in collisions in a way that protects the driver and people inside and outside the vehicle much better than the rigid truck frame.
Crossover SUVs include most luxury imports from Mercedes and Lexus, which were the first to set their SUV grills lower to the ground to match sedan heights and develop vehicle bodies that crumple upon impact like a car, slowing the g-forces that can kill occupants.
Also, as of the last few years, American car manufacturers have made “Bradsher bars” standard in SUVs. Named after Keith Bradsher, the Bradsher bar is a metal bar set behind the grill and designed to crumple into itself to disperse some the g-forces of a crash. Still, many pickups do not feature the bars as standard equipment.
Roof guidelines are also being examined by regulators for possible changes. The current standard was set in 1971 and has not been updated since. GM and other automakers have fought attempts to upgrade the rule, with sometimes contradictory results. Ford submitted data to NHTSA that it claimed would prove why roofs didn’t need to be strengthened, while Volvo, before it was purchased by Ford, stated that it considered roof strength critical to protecting passengers during rollover crashes when it was designing its own SUV.
GM states: “There continue to be misconceptions of basic rollover mechanics. Years of testing show strengthening the roof will not affect the outcome of the crash for the simple reason that the injury mechanics are not related to how much the roof is deformed in a rollover crash.”
Ford attributes the deadliness of rollovers to occupants being thrown around the cab—a problem luxury import cars address with pre-tensioning seat bets, side air bags and other costly features.
Current research points to the paramount importance of vehicle design. “Careful vehicle design plays a more dominant role in vehicle safety than size or weight," Wenzel states. He notes that, at first glance, size alone would seem to be an indicator of safety. But when different manufacturers’ vehicles are measured against one another, the important role of design becomes evident. Foreign-made cars tend to be as safe as or safer than larger U.S.-built vehicles. "For instance," he writes, "the foreign subcompact and compact have almost the same risk as the domestic large and luxury models, while the foreign midsize ones have substantially lower risk than larger domestic models. While at first glance the figure may suggest that, at least within each manufacturer group, vehicle risk [to drivers and occupants] decreases as vehicle size increases, the design factors overwhelm the influence of size,” Wenzel states.
That means that design changes can have significant safety effects and can be a possible avenue toward improving fleet safety, even among SUVs. Comparing the large Ford Excursion to the smaller Toyota RAV4, the Insurance Institute for Highway Safety found that the larger vehicle experienced more than five times as many driver deaths per million registered vehicles annually, significantly above average. “We think this reflects changes in how these vehicles are being made,” said the Institute's Lund, though he could not discount the possibility that driver demographics and driver behavior might also have had some effect, as women are starting to replace young males as the more likely buyers of small SUVs.
On the yardstick of American goals for transportation, behind occupant safety, and inter-vehicle safety, comes high fuel efficiency, and here SUVs are also ahead of pickups, even in the ambitious realm of hybrid vehicles.
Both leading SUV hybrids, the Ford Escape Hybrid, available in 2005, and the Lexus RX400h, promise around 33 miles per gallon, a rating that rivals contemporary full-size sedans. Indeed, the Lexus RX 400h and its other import counterpart, the Mercedes ML, represent SUVs that are achieving the three goals for contemporary personal transportation: occupant safety, safety for vehicles that they crash into and fuel economy. Unfortunately (from the point of view of their adding to the overall safety of the fleet), these vehicles are reserved for the very affluent, costing in excess of $40,000.
Also, it should be noted that although SUVs continue to undergo rapid design development to increase safety for crash victims inside them and out, millions of older vehicles remain on the road and will begin to change ownership over the next few years. Of potential concern is the likelihood that they will be purchased by younger drivers who are statistically less safe. By 2010, Bradsher predicts half the vehicles on the road will be SUVs, many aged, poorly maintained and characterized by more dangerous designs—the same type of designs that continue to be passed on to generation pickups.
As both design and technology have moved forward for SUVs, the rest of the truck fleet is not under public or government pressure to evolve, and pickups' popularity has proven impervious to safety or, for the moment, even fuel economy concerns. March 2005 was the single biggest month for large pickup truck sales, GM reported. Jay Miller with the Patriot Ledger newspaper in Massachusetts commented on the continuing growth of truck sales despite the decline in SUV sales: “In the old days the common image of a pickup truck was a vehicle for either a working man intent on building things, or a outdoorsman who probably had a couple of hunting dogs in the back. But in 2005, the humble old pickup truck has become a multi-purpose ride, every bit as versatile as the Sport Utility Vehicle, and often more luxurious than your daddy's Cadillac. SUV's may have opened America's eyes to the concept of a vehicle that could perform many functions while also navigating in a wide variety of conditions on and off the road. In recent years, more and more buyers have been finding that pickup trucks offer many of the same features, along with the added bonus of a real cargo bed for hauling stuff, whether it be trash, luggage, furniture, or sports equipment.”
Manufacturers report that pickups have reached the point where full-size models sit 1-2-3 atop the annual "Top 25 Sales" chart and a compact model is ranked 15th. Their strong finish pushed the top-selling car, Toyota’s Camry, down to fourth.
Conversely, SUV sales are down, compared to their high mark in 2002. The newly redesigned and safer crossover utility vehicle (CUV) is drawing customers from the SUV market. CUV sales increased by 34.7 percent in 2002 and now have 9 percent of the national market, according to the National Automobile Dealers Association (NADA).
In the final view, Wenzel's and other recent researchers' work clearly illustrate that despite SUVs' compatibility and rollover problems, they are actually less menacing siblings than their older brother, the staid pickup. They are also more mutable, as seen in the continuing development and acceptance of crossovers and advances in design and technological fixes for some of their shortcomings.
The older sibling however, rumbles on,
relatively unchanged and appears to have the potential to keep doing so
for a long, long time.
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