Small Cars Need Improvements In Side, Rear Collisions

New small cars generally received good ratings for frontal crashes, but they fare worse when tested in side and rear collisions, according to the Insurance Institute for Highway Safety (IIHS).

IIHS said it tested seven 2009 small car models from various auto manufacturers. All cars tested earned the highest rating of "good" for frontal crashes, but only the Suzuki SX4 and Toyota Matrix (and its twin, the Pontiac Vibe) earned good ratings for side crashes.

However, the IIHS said side protection has improved since 2006. For the 21 current small cars rated by IIHS, 11 earned good ratings for side protection. IIHS said in 2006, only three of 19 small cars tested earned good ratings, and most cars earned poor ratings.

Additionally, IIHS senior vice president Joe Nolan noted, "Side airbags were mostly optional in the 2006 round of small car tests. A major change is that side airbags are standard in all of the seven small cars we tested this time around."

And side airbags designed for head protection are crucial for smaller cars, the IIHS said, because of where these cars are struck in a side collision.

The IIHS said side impact tests for small cars are "especially challenging" because the barrier that strikes the test vehicle represents the front end of a pickup truck or SUV, and therefore the barrier hits the car at head level.

For rear impacts, the IIHS said many automakers haven't paid as much attention to this area compared to front and side impacts.

Mr. Nolan said neck sprains or strains, which are frequently reported in U.S. insurance claims, occur when a vehicle is struck in the rear, and the head of the occupant lags behind the forward torso movement, causing the neck to bend and stretch. Good seat/head restraints can mitigate the consequences of rear collisions, but the IIHS said that, in small cars, only the Ford Focus received a good rating in this area out of the seven tested cars.

"In stop and go commuter traffic, you're more likely to get in a rear-end collision than any other kind of crash," Mr. Nolan said. "It's not a major engineering feat to design seats and head restraints that afford good protection in these common crashes."

Speaking to improvements that should be made for small cars, the IIHS said electronic stability control (ESC) should be standard for these vehicles. ESC helps reduce rollovers, the IIHS explained, and even though small cars are not as susceptible to rollovers as SUVs, the consequences for small cars can be deadly.

Out of the seven tested cars, only the Chevrolet HHR and Pontiac Vibe have standard ESC. It isn't available at all on the Chrysler PT Cruiser, and it is optional on the rest. "The smallest cars that most need this crash avoidance feature often don't have it," Mr. Nolan said.

The seven cars tested were the Suzuki SX4, the Toyota Matrix/Pontiac Vibe, the Ford Focus, the Chevrolet HHR, the Hyundai Elantra, the Saturn Astra and the Chrysler PT Cruiser.

For side collisions, the SX4 and Matrix/Vibe scored good; the Focus and HHR scored acceptable; the Elantra and Astra scored marginal; and the PT Cruiser scored poor. For rear collisions, the Focus scored good; the Elantra and Astra scored acceptable; the SX4 and HHR scored marginal; and the PT Cruiser scored poor.

The Mini Cooper was also tested in a separate "minicar" category and scored good in front and rear impacts and acceptable in side impacts.

The IIHS said front impacts are based on the results of 40 mph frontal offset crash tests. Side evaluations are based on performance in a crash test in which the side of a vehicle is struck by a barrier moving at 31 mph. Rear crash tests measure head restraint geometry and simulates a collision in which a stationary vehicle is struck in the rear at 20 mph.