本文发表在 rolia.net 枫下论坛All other things being equal, occupants in a bigger, heavier vehicle are better protected than those in a smaller, lighter vehicle. Both size and weight affect the forces people inside a vehicle experience during a crash. The magnitude of those forces is directly related to the risk of injury.

In the case of size, the longer distance from the front of the vehicle to the occupant compartment gives a bigger vehicle an advantage in frontal crashes, which account for half of passenger vehicle occupant deaths. The longer that distance, the bigger the crush zone, and the lower the forces on the occupants.

Weight comes into play in a collision involving two vehicles. The bigger vehicle will push the lighter one backward during the impact. As a result, there will be less force on the occupants of the heavier vehicle and more on the people in the lighter vehicle. Heavier vehicles also fare better in some single-vehicle crashes because they are more likely to move, bend or deform objects they hit.

IIHS demonstrated the role of size and weight in a series of crash tests in 2009 in which a microcar and two minicars were each crashed into a midsize car from the same manufacturer. The Smart Fortwo, Honda Fit and Toyota Yaris all had good ratings in the Institute’s moderate overlap frontal test, but all three performed poorly in the crashes with midsize cars. 1更多精彩文章及讨论，请光临枫下论坛 rolia.net

本文发表在 rolia.net 枫下论坛A lighter vehicle will always be at a disadvantage in a collision with a heavier vehicle. Beyond weight differences, SUVs and pickups historically have posed a danger to people in cars because their energy-absorbing structures didn’t line up with those of lower-profile vehicles. As a consequence of such incompatible designs, cars would often underride SUVs and pickups, resulting in more severe damage and a higher risk of injury and death. An analysis of crashes in 2000-01 involving 1997-99 model vehicles showed that SUVs and pickups were much more likely than cars or minivans of the same weight to be involved in crashes that killed occupants of other cars or minivans. 4


This mismatch has faded as a problem in recent years, thanks to new designs of SUVs and pickups. The energy-absorbing structures of these vehicles are now lower so that they line up better with those of cars. The new designs came out of a voluntary agreement forged by automakers, the government and IIHS in 2003. A more recent study of 2008-09 crashes involving 2005-08 models showed that SUVs were no more likely than cars to be in crashes in which occupants of other cars died. 5 Pickups still killed people in other vehicles at a higher rate, but the difference was much smaller than it was previously.更多精彩文章及讨论，请光临枫下论坛 rolia.net

http://www.iihs.org/iihs/topics/t/vehicle-size-and-weight/fatalityfacts/passenger-vehicles