One of the main causes of single vehicle accidents and general car wrecks is tire blowouts. If a tire comes apart when a vehicle is traveling at high speeds, the vehicle will likely swerve and/or roll over. These types of accidents are extremely dangerous, because an occupant could be thrown from the vehicle, crushed by the roof, or injured by the vehicle's interior. Tire blowouts can be caused by a number of things: excessively low tire pressure, heavily or unevenly worn tires, tire puncture, or defective tires. Certain types of vehicles - SUVs, for instance - are more likely to roll over after suffering a tire blowout, because they have a high center of gravity and are prone to flip.

In August of 2000 Firestone announced the recall of several tire models produced at an Illinois plant. Firestone ATX, ATX II, and Wilderness AT tires from the Decatur factory were recalled due to a number of tread separation and blowout incidents. There were a number of serious injuries and fatalities from the resulting accidents. Those particular tire models had been installed standard on certain Ford vehicles, most notably Explorer SUVs. Due to the high incidence of rollover crashes involving Ford Explorers, the NHTSA launched an investigation into the issue and eventually discovered that defective tires were behind many of these accidents. Ultimately, millions of tires were recalled, and a number of victims and families have sued Firestone and Ford for compensation.

Crashworthiness: Overview

Crashworthiness is the ability of a vehicle to prevent injuries to the occupants in the event of a collision. Crashworthiness deals primarily with the 'second collision' in which the driver and passengers collide against the interior of the vehicle. The cause of the accident is usually considered irrelevant in crashworthiness cases.

There are two important questions to consider when determining crashworthiness:

• Could the vehicle occupants have fared better?
• Could some feature that was lacking in the vehicle have reduced the occupants' injuries?

It is also important to remember that crashworthiness is not the same as vehicle safety. Vehicle safety is determined by both crashworthiness and accident avoidance features such as anti-lock brakes and wider tires. Crashworthiness features include roll bars, airbags, seat belts, headrests, side impact protection, and crumple zones. Crashworthiness features are designed to minimize occupant injuries, prevent ejection from the vehicle, and reduce the risk of fire.

Vehicle Defects

Crashworthiness cases typically involve injuries that are sustained as a result of a defect in a vehicle. There are three types of product defects that can lead to injury:

• Manufacturing defects - injury occurs when there is a flaw in the manufacturing process. For example, failure to include an airbag when the design calls for it is a manufacturing defect.
• Design defects - injury occurs when a vehicle is unsafe because of the manufacturer's design. For example, a fuel tank placed in a location that makes it likely to explode upon impact is a design defect.
• Failure to warn - injury occurs when the manufacturer is aware of a dangerous aspect of a vehicle but fails to warn or provide adequate warning to consumers.