Indianapolis - Five major crashes, some involving cars becoming airborne and flipping over, have raised concerns entering Sunday's 99th running of the Indianapolis 500.
The famed IndyCar oval classic, 200 laps around the 2.5-mile (4km) Indianapolis Motor Speedway, will start with New Zealand's Scott Dixon in pole position followed by Australian Will Power and France's Simon Pagenaud.
But tensions are raised at the "Brickyard" after wrecks that prompted officials to alter qualifying specifications to reduce turbo engine boost and increase downforce to slow cars in hopes of avoiding more spectacular crashes.
Three-time Indy 500 champion Helio Castroneves went airborne and had his car flip end over end in practice.
While Britain's Pippa Mann stayed on the track when she hit the outer wall and outer pit wall entrance, American Josef Newgarden also found the safety fencing in a testing session.
When two-time pole sitter Ed Carpenter went airborne in a crash ahead of Sunday's qualifying, IndyCar officials made last-minute safety changes, somewhat controversially since only Chevrolet-powered cars were having the issue at speed and those powered by Honda engines were not affected.
"We've said all along we want to go faster, but we want to do it safely," IndyCar parent company chief executive Mark Miles said. "Safety for drivers and fans is the top priority."
Officials forced teams to use slower race set-ups for time trials, but there is some uncertainty about what will happen when the full 33-car field takes the green flag even after the qualifying slowdown.
"We don't want to see cars getting in the air and there's only a few tools that you have in the toolbox to use and IndyCar, whether it's the right or wrong situation, for safety, it's kind of all they had," Dixon said.
"If you look at oval racing as some of the most dangerous... it's always in the back of your mind."
On Monday, Canada's James Hinchcliffe suffered pelvic and left thigh injuries that have sidelined him indefinitely in a crash caused by the failure of a suspension component.
Aussie Ryan Briscoe will replace him in the lineup on Sunday.
Although Hinchcliffe was seriously injured, at least his car stayed on the ground.
AFP
