Drivers want to save time, and local transportation agencies want to improve traffic flow, but at what cost? With posted speed limits increasing on roadways around the country, a vehicle's ability to protect drivers in crashes is in doubt.
Small speed increases can have huge effects on crash outcomes, as shown in new crash tests by the AAA Foundation for Traffic Safety, the Insurance Institute for Highway Safety (IIHS) and Humanetics.
The safety organizations conducted crashes at three different impact speeds---40, 50 and 56 mph. They found the slightly higher speeds were enough to increase the driver's risk of severe injury or death.
Drivers often travel faster than posted speed limits, but when officials raise limits to match travel speeds, people still go faster. Today, 41 states allow 70 mph or higher speeds on some roadways, including eight states that have maximum speeds of 80 mph or more.
A 2019 IIHS study found that rising speed limits have cost nearly 37,000 lives over 25 years. AAA and IIHS urge policymakers to factor in this danger from higher speeds when considering speed limit changes.
"We conducted these crash tests to assess the effect of speeds on drivers and learned that a small increase could make a big difference on the harm to a human body," said Dr. David Yang, executive director of the AAA Foundation for Traffic Safety. "A speeding driver may arrive at their destination a few minutes faster, but is the tradeoff of getting severely injured or even losing one's life worth it if a crash occurs?"
The AAA Foundation collaborated with IIHS and Humanetics to examine how speed affects the likelihood and severity of occupant injury in a crash.
Three 2010 Honda CR-V EX crossovers were used because they represented the average age---11.8 years---of a typical vehicle on U.S. roadways and earned the top rating in the IIHS moderate overlap front test.
Calspan Corporation conducted all the tests in its crash laboratory in Buffalo, NY.
As the crash speed increased in the tests, researchers found more structural damage and greater forces on the dummy's entire body.
"Higher speed limits cancel out the benefits of vehicle safety improvements like airbags and improved structural designs," said Dr. David Harkey, IIHS president. "The faster a driver is going before a crash, the less likely...