Arnold won the
1930 Indianapolis 500 after leading all but first two laps of the race, the most ever by a winner of the race and he won by a margin of 7 minutes and 17 seconds. He was 24 years old at the time. In
1931, he led 155 laps but crashed on lap 162 while holding a five-lap lead, sustaining serious injuries along with his riding mechanic
Spider Matlock. A tire came off the car, bounced over the stands and killed 11-year-old Wilbur Brink, who was struck near his parents' concession stand outside the track. In
1932 Arnold led 57 laps before crashing on lap 59. He sustained a broken shoulder and
riding mechanic Matlock sustained a broken pelvis. At the urging of his wife, Arnold retired from racing. == Military service ==