Chaos at the track as wreck happens before race even starts, then one car flies over another

How does this happen?

The IndyCar race at Gateway Motorsports Park devolved into early chaos, and the best way to describe it is to show you want happened.

First Tony Kanaan spun out on the final parade lap, bringing out a caution flag.

NESN reported that his crew was able to repair the damage, though Kanaan started three laps behind.

Then, on the restart, Josef Newgarden the championship leader, made a move around the outside of Will Power, and Power spun out. Driver Ed Carpenter then went over the TOP of Power's car and into the wall.

Both driver's were ok.