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This paper describes the development of a non-linear finite element model of a commuter category aircraft seat designed to explore the issue of energy absorption in severe, but survivable, crashes. Using a reference seat, the paper presents a description of the model and the results of finite element modeling of the seat at increasingly severe impact velocities. The paper presents the results of a parallel experimental program, conducted to validate the model, in which instrumented crash dummies were drop tested in the reference seat at the same impact velocities as the simulation. Experimental results are reported for passenger lower lumbar loading, peak pelvic acceleration, and seat structural loading.

In the United States, passenger vehicles are shifting from a fleet populated primarily by cars to a fleet dominated by light trucks and vans (LTVs). Because light trucks are heavier, stiffer, and geometrically more blunt than passenger cars, they pose a dramatically different type of threat to pedestrians. This paper will investigate the effect of striking vehicle type on pedestrian fatalities and injuries. The paper will present and compare pedestrian impact risk factors for sport utility vehicles, pickup trucks, vans, and cars as developed from analyses of U.S. accident statistics.

Several research studies have concluded that light trucks and vans (LTVs) are incompatible with cars in traffic collisions. These studies have noted that crash incompatibility is most severe in side crashes. These early research efforts however were conducted before complete introduction of crash injury countermeasures such as dynamic side impact protection. Based upon U.S. traffic accident statistics, this paper investigates the side crash compatibility of late model cars, light trucks and vans equipped with countermeasures designed specifically to provide side crash protection. The paper explores both LTV-to-car crash compatibility and crash incompatibility in car-to-car collisions.

The effectiveness of Forward Collision Warning (FCW) or similar crash warning/mitigation systems is highly dependent on driver acceptance. If a FCW system delivers the warning too early, it may distract or annoy the driver and cause them to deactivate the system. In order to design a system activation threshold that more closely matches driver expectations, system designers must understand when drivers would normally apply the brake. One of the most widely used metrics to establish FCW threshold is Time to Collision (TTC). One limitation of TTC is that it assumes constant vehicle velocity. Enhanced Time to Collision (ETTC) is potentially a more accurate metric of perceived collision risk due to its consideration of vehicle acceleration. This paper compares and contrasts the distribution of ETTC and TTC at brake onset in normal car-following situations, and presents probability models of TTC and ETTC values at braking across a range of vehicle speeds.

Crash incompatibility between disparate classes of passenger vehicles is an issue of growing global concern. There is widespread consensus, both in the U.S. and internationally, that any regulation or test procedure focusing on crash compatibility should be a globally harmonized standard. However, this may prove to be a challenging effort due to huge differences in U.S. and international fleet composition. The U.S. fleet is dominated by a growing light truck component, and has few of the sub-1000 kg cars that are prevalent in Australian and European fleets. This paper will examine the structure of the passenger vehicle fleets in the U.S., Europe, and Australia, the relationship between fleet composition and real world crash fatalities and the prospects for a single, globally accepted, crash compatibility test procedure.

In a side impact, the occupants on both the struck, or near side, of the vehicle and the occupants on the opposite, or far side, of the vehicle are at risk of injury. Since model year 1997, all passenger cars in the U.S. have been required to comply with FMVSS No. 214, a safety standard that mandates a minimum level of side crash protection for near side occupants. No such federal safety standard exists for far side occupants. The mechanism of far side injury is believed to be quite different than the injury mechanism for near side injury. Far side impact protection may require the development of different countermeasures than those which are effective for near side impact protection. This paper evaluates the risk of side crash injury for far side occupants as a basis for developing far side impact injury countermeasures. Based on the analysis of NASS/CDS 1993–2002, this study examines the injury outcome of over 4500 car, light truck, and van occupants subjected to far side impact.

Light trucks and vans (LTVs) currently account for over one-third of registered U.S. passenger vehicles. Yet, collisions between cars and LTVs account for over one half of all fatalities in light vehicle-to-vehicle crashes. Nearly 60% of all fatalities in light vehicle side impacts occur when the striking vehicle is an LTV. This paper will examine this apparent incompatibility between cars and LTVs in traffic crashes. An analysis of U.S. crash statistics will be presented to explore the aggressivity of LTVs in impacts with cars and identify those design imbalances between the cars and LTVs, e.g., mass, stiffness, and geometry, which lead to these severe crash incompatibilities.