Each year, as part of the New Car Assessment Program (NCAP), the government buys brand new cars right off the lots and crashes them. Why? To compare how well different vehicles protect front-seat passengers in a head-on collision. Results are given in a one-to-five star rating, with five stars indicating the most protection, and one star, the least.
Federal law requires all passenger cars to pass a 30 mph frontal crash test. NCAP tests are conducted at 35 mph to make the differences between vehicles more apparent. The tests are equivalent to a vehicle moving at 70 mph striking an identical parked vehicle.
During the test, instrumented dummies wearing safety belts measure the force of impact to the chest, head, and leg. These readings are the basis of the star rating.
Theft ratings are compiled from information provided by the Federal Bureau of Investigation and vehicle manufacturers. NHTSA calculates a theft rating for each vehicle based on the number of vehicles stolen and the number of vehicles manufactured.
Based on the latest information available, a mid-point theft rate is calculated. Vehicles with theft ratings above or below that value on noted.
Air bags inflate instantly in frontal crashes to prevent occupants from hitting the dashboard, steering wheel or windshield at speeds as low as 15 mph. Air bags do not eliminate the need for safety belts, and offer no protection in rollovers, rear, or side impacts.
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What's the most important piece of safety equipment in your vehicle?
Safety belts continue to be your best protection in a crash.
To be most effective, they must be adjusted properly: pulled tightly across the pelvis, without slack in the shoulder strap. Adjustable anchors change the height of the shoulder strap to improve belt fit, and are especially helpful for smaller people.
Anti-lock brakes prevent a vehicle's wheels from locking up during "panic" braking, and allow the driver to retain steering control. While ABS has long been used by race car drivers, it doesn't allow you to drive like one. ABS does not stop the vehicle any faster and you may still lose control with excessive speed or extreme steering.
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The correct way to use ABS is to "stomp and steer" -- to hold down firmly on the brake pedal and not let up as the vehicle slows. Unlike other systems, you don't pump anti-lock brakes. Some ABS systems make noise and vibrate the brake pedal when the system is working. Continue to apply the brakes despite noise or vibration. |
Side impact crashes are the second-leading cause of death and injury to passenger car occupants. The government requires all 1997 model year passenger cars to have this protection. Many new models provide it ahead of schedule.
The crash test results include three principal data points: Head injury (HIC); Chest injury (chest G); and leg injury (femur load). The lower the numbers are for the head, chest, and the femur load, the lower the potential is for injury in a 35 mph frontal crash.
All of the vehicles are crashed into a fixed barrier at a speed of 35 mph. The impact is the same as if two identical vehicles, each going 35 mph, collided head-on. Each test vehicle carries two dummies of average human size and weight, one in the driver's seat and one in the right front passenger seat. The dummies contain instruments in their heads, chests, and thighs which measure the forces and impacts that occur during the crash and could cause injury. These measures form the basis for the numbers on the chart.
There are two types of dummies used in NCAP tests, the Hybrid II and Hybrid III. While NHTSA considers the dummies equally effective in measuring crash protection, Hybrid III dummies are more advanced and can provide more detailed injury data. By 1996, Hybrid III dummies will be used exclusively in all NCAP tests.
They are chosen from those models that are new, potentially popular, redesigned with structural changes, or have improved safety equipment, such as an air bag. The vehicles are bought from new car dealers' lots and are not supplied by the manufacturer. Only one of each model is tested.
Since 1979, the New Car Assessment Program (NCAP) has crash-tested about 35 new models every year to find out how well they would protect the driver and front seat passenger in a head-on crash. Crash test results on models that have no basic changes are carried over to the next year, so results are available on about 80% of the new cars sold. The tests are conducted by the National Highway Traffic Safety Administration, an agency within the U.S. Department of Transportation.
A "passive" or automatic safety belt system provides frontal crash protection for occupants while requiring no action by the occupant to buckle the belt. In a "manual" system, the occupants must actively move the safety belt into place and buckle it.
Automatic safety belts come in two general types, a motorized and a door mounted system. In a motorized system, the shoulder belt is attached to a track over the door and is operated by a small electric motor. When the door is closed and the ignition key is turned on, the shoulder belt automatically moves into place to provide frontal crash protection. No action is required by the occupant. A manual lap belt is normally provided with a motorized system. For the best protection, the lap belt must be used. The door mounted system often includes the shoulder and the lap belt, similar to the manual safety belt. The door mounted system automatically places the shoulder and lap belts on the occupant when the door is closed. However, some door mounted systems may only include a shoulder belt. For these, a manual lap belt also is supplied.
The air bag is another form of automatic crash protection because it deploys when a severe frontal crash occurs, automatically protecting the occupant. An air bag equipped vehicle will generally have a manual shoulder and lap belt system. However, a few vehicles have an air bag and a passive safety belt system, as listed above. The belt system always should be used with the air bags for the best available protection.
Charts, test reports and 16mm films of each test are available for a fee upon request to the National Crash Analysis Center:
Telephone is (703) 726-8226
FAX is (703) 726-8358
email: library@ncac.gwu.edu