"Arnie" Knepper (October 10, 1930 – June 6, 1992), was an American racecar driver.
Born in Belleville, Illinois, Knepper also died there from cancer.
He drove in the USAC Championship Car series, racing in the 1963–1972 seasons, with 75 career starts and finished in the top ten 21 times.
Knepper earned a small place in Indianapolis lore when he crashed on the 87th lap of the 1969 Indianapolis 500, and instead of making the typical dash to trackside safety, stood up on his car and, facing 180-mph oncoming traffic, frantically waved his arms to warn oncoming drivers of the danger.
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