The drivers don't like to talk about it. IndyCar isn't crazy about the subject, either. But there's no getting around the danger of open-wheel racing.
You don't have to be a genius to figure out why. Take Sunday's Grand Prix of Baltimore.
For openers, you'll have 25 cars racing at ridiculously high speeds around a tight 2.04-mile course in the heart of a city.
Throw 25 super-competitive drivers into the mix. Now add road surface changes from concrete to asphalt, 300 manhole covers, blind turns and light-rail tracks and the potential for disaster is everywhere.
"These tracks really bring out the animal in a driver," said Arie Luyendyk, a two-time Indianapolis 500 champion who's a steward for Sunday's race. "You have to be in attack mode. If you're going to be apprehensive, you're not going to be quick."
And quick — at straightaway speeds of 170 miles per hour and cornering speeds of 75 — is what every driver shoots for in these races.
Out on the course, apprehension kills.
Maybe even more than speed does.
"Anytime you're driving with hesitation or fear, you're a danger to other people on the track," said Mike Conway, driver of the A.J. Foyt Racing Honda.
That's why that little incident Friday that sent cars airborne at the light-rail tracks on Pratt Street had drivers so stressed.
Airborne isn't good for a car if you're just backing out of the driveway. When you're hitting speeds of 130 over a bump during a practice run, it can be terrifying.
So when Simon Pagenaud's Schmidt Hamilton Honda flew three feet in the air and a couple of other cars had similar experiences, the drivers weren't happy.
"I took off like a plane," Pagenaud said. Only without beverage service and an in-flight movie.
"Some drivers were complaining that their backs hurt from the concussion, too," Luyendyk said. "They're not in a Cadillac out there. The seats don't compress to where it's comfortable."
A chicane — a series of turns to slow speeds — was built on Pratt for last year's race. It was originally left out when the track was set up this year because the drivers wanted to go faster and be able to pass.
But when a tire chicane was added Friday after the flying adventures of Pagenaud and the others, none of the drivers thought it was a wuss move on IndyCar's part.
Sometimes courage has to give way to common sense.
Still looming over IndyCar, of course, is the death of two-time Indianapolis 500 champion Dan Wheldon. Wheldon died in a 15-car pileup last October at the IndyCar World Championship in Las Vegas.
The accident shook the sport to its core.
"For sure, losing Dan was a huge blow to everybody, to the sport, to the racing community, to each of us individually for different reasons," said James Hinchcliffe, driver of the GoDaddy Chevrolet. "That's something I think we'll all carry with us for the rest of our lives."