Cars and SUVs equipped with automatic braking systems intended to prevent or mitigate certain low-speed crashes were involved in 38 percent fewer rear-end injury crashes in Australia and Europe than comparable models without the technology, a new meta-analysis by the Australian New Car Assessment Program (ANCAP) and European New Car Assessment Programme (Euro NCAP) indicates.
Researchers examined the real-world experience of passenger vehicles equipped with autobrake systems designed to operate at speeds up to 30 kph (19 mph). The study looked at two-vehicle injury crashes in which a case vehicle struck the rear of another vehicle or the case vehicle itself was struck in the rear. The analysis compared the ratio of these crash types for autobrake vehicles and similar vehicles without autobrake. Data were from Australia and five European countries and included 2009 and later police-reported crashes.
The majority of the case study vehicles were 2008-12 Volvos (S60, S80, V40, V60, V70, XC60, XC70) with City Safety, a low-speed front crash prevention system standard on Volvos since the 2008 model year. Some autobrake models from Volkswagen (CC, Up) and Mazda (6, CX-5) also were included.
A separate analysis by Swedish insurer Volvia/If found that the overall claim frequency of front-to-rear collisions was 28 percent lower for Volvos with the first or second generation of City Safety with autobrake capabilities up to 19 or 30 mph compared with Volvos without the feature. The study included data from claims filed for crashes in Sweden between July 1, 2012, and June 30, 2014, involving 2010 and later models.
The findings of both studies are in line with HLDI analyses indicating that City Safety is reducing insurance losses.
The ANCAP/Euro NCAP researchers note that an unintended consequence of improved braking could be that vehicles with autobrake are more often struck in the rear. This might result in an overestimation of the autobrake vehicle's ability to avoid striking the rear of another vehicle.
Research by HLDI, however, indicates that vehicles with autobrake aren't more likely than other vehicles to be hit from behind. Analysts examined the point of impact for S60s and XC60s with City Safety and for comparable vehicles without a low-speed front crash prevention system repaired under PDL coverage. These analyses would reveal if there were any increases in crash configurations where another vehicle was at fault. HLDI couldn't find any measurable difference between the study and control groups, indicating that City Safety doesn't increase the likelihood of being struck in the rear.
Euro NCAP says its findings support the group's decision to include autobrake as a factor in its safety ratings program for consumers. Both NCAPs are making a push to require the feature as standard in new vehicles sold in Australia and Europe.
The National Highway Traffic Safety Administration in January announced plans to add autobrake to the U.S. NCAP's list of recommended advanced safety features.
Under the IIHS ratings program, a front crash prevention system with autobrake is one of the criteria required to earn a Top Safety Pick+ award. IIHS assigns models with available front crash prevention systems basic, advanced or superior ratings based on system type and performance in track tests.