Collision warning, emergency braking cut rear-end crashes in half, study finds

WASHINGTON — Front-to-rear crashes were slashed by about half when the striking vehicle was equipped with forward-collision warning and automatic emergency braking, according to a study from a partnership between the U.S. Department of Transportation and several automakers.

The Partnership for Analytics Research in Traffic Safety on Tuesday released the results of what it called "the largest government-automaker study to date" exploring the real-world effectiveness of advanced driver-assistance systems in passenger vehicles.

The group, formed in 2018, is a voluntary partnership between the Transportation Department and automakers such as General Motors, Honda, Mazda, Nissan, Stellantis and Toyota.

Ford Motor Co. also has joined the partnership, and its vehicles will be incorporated into future studies, the group noted.

Tesla Inc., whose Autopilot driver-assist system is under federal investigation, is not part of the group.

The study — conducted by Mitre Corp., a nonprofit that operates the partnership as an independent third party — comes as automakers add more advanced driver-assistance features to their vehicles and as NHTSA collects data on crashes linked to those technologies.

"These emerging technologies can substantially reduce the number of crashes and improve safety outcomes," said Tim Czapp, industry co-chair of the partnership's governance board and a senior manager at Stellantis. "Demonstrating industry's proactive commitment, [automatic emergency braking] is approaching standard deployment and with real-world effectiveness is helping mitigate injuries and lives lost."

In addition to forward-collision warning and automatic emergency braking — including those systems with pedestrian detection — the group assessed lane-departure warning, lane-keeping assistance and lane-centering assistance.

The study relied on vehicle equipment data provided by participating automakers for 47 million light-duty vehicles from the 2015-20 model years, and data provided by NHTSA from 12 million police-reported crashes across 13 states.

Overall, the study found that driver-assist features such as forward-collision warning and automatic emergency braking provide "substantial safety benefits across a variety of situations," while others such as lane-departure warning and lane-keeping assistance provide "some benefit."

Features such as automatic emergency braking with pedestrian detection require "more data to make estimates of effectiveness," according to the findings.

Still, front-to-rear crashes resulting in injury were reduced by 53 percent for vehicles with both forward-collision warning and automatic emergency braking equipped. Front-to-rear crashes considered "serious" were reduced by 42 percent in vehicles with the two technologies, the analysis showed.

When vehicles are equipped with just forward-collision warning, the estimated reduction for all front-to-rear crashes is 16 percent, and 19 percent for front-to-rear crashes resulting in injury.

The study also demonstrated that automatic emergency braking performs "extremely well in all conditions, even when roadway, weather and lighting conditions are not ideal."

A study from AAA in September that crash-tested four different makes and models with the feature found plenty of room for improvement, however. Another study released in August by the Insurance Institute for Highway Safety that tested vehicles’ ability to detect pedestrians at night found automatic braking systems performed poorly in that situation.

Jennifer Morrison, Mazda's manager of vehicle safety compliance, planning and development, said in a statement that the latest study is "a starting point for much to be learned from this first-of-its-kind data sharing effort in automotive safety."

Forward-collision warning and automatic emergency braking are standard equipment on all U.S. Mazda vehicles, she noted.

"A crucial part of the 'safe system approach' is making vehicles safer by leveraging innovation to prevent crashes and save lives on our nation's roads," Ann Carlson, NHTSA's acting administrator, said in a statement. "Public-private partnerships are yet another tool to help accelerate the development and adoption of life-saving technology to protect all road users."