Harry Barr soloed on January 16, 1955 and passed his private license check ride on July 3, 1955. With his partner, Donald Duncan, he founded Duncan Aviation, currently employing more than 1,700 aviation professionals. They also created Panhandle Aviation, operating a fleet of helicopters to support missile site construction.

For twenty-four years, he contracted for support services for government operations for the United States Bureau of Land Management in Alaska. As an active member of the Lincoln Sport Parachute Club, Barr made more than seventy jumps. He is a founding member of the Midwest Aerobatic Club and participated in numerous aerobatic contests and air shows.