DAYTONA BEACH, Fla. — Dale Earnhardt Jr. traded in his T-shirt, jeans and sneakers for a head-to-toe pilot uniform, climbed up the portable stairs and slipped into the cockpit of the iconic Goodyear Blimp. He kept his head down and turned away from a 65-year-old military veteran who thought he was onboard for a once-in-a-lifetime ride.