It's Probably Safe to Drop That Top: IIHS

Just apply sunscreen first.

While most Americans hold reservations about going topless, preferring staid modesty over outlandish exhibitionism, many still enjoy kicking up their heels and getting the most out of life. Luckily for them, several automakers are only too happy to play along. And if that sort of thing’s your bag, the Insurance Institute for Highway Safety has good news for you.

Your convertible is likely just as safe as the coupe version of the same vehicle.

While the days of massive Detroit land yachts with bodies as rigid as Gumby and windshield frames thinner than Kate Moss are long behind us, the stigma they lent to top-down driving still looms over some psyches. No one wanted to be involved in a T-bone or rollover accident in one of those machines. As such, driving one took on an element of danger.

Clearly, their drivers were full of life.

Nowadays we have reinforced A-pillars and sturdy door beams and stability control and, in some cases, pop-up roll bars. Rollover protection is greatly increased in all new models, regardless of roof type.

This seems to be borne out in fatality data collected by two National Highway Traffic Safety Administration reporting systems and combined by the IIHS. In studying the rate of crashes and subsequent fatalities in 1- to 5-year-old vehicles from 2014 to 2018, the institute found that “both crash rates and driver death rates were lower for convertibles than for nonconvertible versions of the same cars.”

The IIHS noted that the difference in death rates between the two weren’t great enough to be significant. Still, the data shows that the old misconception about driving a drop-top is exactly that.

From the IIHS:

[IIHS Director of Statistical Services Eric Teoh] found that convertibles were involved in 6 percent fewer police-reported crashes per miles traveled than their conventional counterparts. Driver death rates were 11 percent lower. However, the likelihood that the driver was ejected from the vehicle in the event of a fatal crash was higher for convertibles than conventional versions.

Previous research has shown that for conventional cars a stronger roof reduces the risk of a serious or fatal injury as well as the likelihood of ejection in the event of a rollover crash. IIHS added a roof-strength evaluation to its crashworthiness testing program in 2009, making a good rating a requirement for the TOP SAFETY PICK award a year later.

It’s worth noting that convertibles currently on the market are either pored-over, painstakingly optimized sports cars or high-end fare (or both). Gone are the days when you could hop into a Chevrolet Cavalier or Dodge Shadow drop-top. Whether the elimination of the mainstream, low-end convertible market skews these findings in favor of coupe-convertible safety parity is unknown.

While the NHTSA data shows you’re not more likely to die in a convertible, the manner in which you depart this earth could indeed differ. The types of crashes incurred by both body styles were near identical, but convertible drivers are more likely to die via ejection than coupe drivers (21 percent vs 17 percent). Not surprisingly, the frequency of occupant ejection increases during rollover crashes.

Does data suggest that free-spirit convertible drivers flout road rules? Not really.

“Convertible drivers were slightly more likely to be wearing seat belts and slightly less likely to be speeding, though they were a bit more likely to be impaired by alcohol,” the IIHS stated. “These differences were too small to suggest a big variation in driver behavior for the two vehicle types.”

[Image: Ford, Murilee Martin/TTAC]