he is banging a black woman
In their world, it could be just a business move.
Lucas stated he has been trying to get funding for this movie for about 20 years. The black woman he is dating is president of Ariel Capital, a mutual fund based in Chicago. The founder of that fund is a black man from Chicago who first started with Charles Schwab, the large stock discount brokerage.
It wouldn't surprise me if much of "his" funding came from that mutual fund.
As far as the movie goes, anyone who knows about the Tuskegee Airmen knows it was Eleanor Roosevelt, wife of then president Franklin Roosevelt who pushed to have black pilots. President Roosevelt was going to scrap the project because many of his advisors told him blacks weren't smart enough to fly planes. Eleanor Roosevelt had saw a black man fly a plane during the Paris World Fair in France in 1912. He was the best pilot of all of them which really impressed Eleanor.
If they really wanted to push a white person for the central theme, they could have pushed her out in front. But putting a white woman out front in a World War II movie may have seemed a bit much for some.
During World War II, the general of the Air Force for the United Stated was a black man, General Benjamin O. Davis. He was in charge of the unit that escorted B-52 bombers during bombing raids in Europe which was what the Tuskegee Airman were trained to do. That plus the fact that the military was segregated at that time and I can see why it was hard press to find a white person who was involved with the Tuskegee Airman success other than Eleanor Roosevelt.
When I was growing up in Detroit, the mayor of the city was a former Tuskegee Airman. We use to read about them when I was in junior high school which is why I know so much about them. They would also come to our schools on career day.