As a kid I was around a lot of prop driven planes, including a B-17. Yes I am old. lol

In high school we were right next door to the Confederate Air Force, when they were in Harlingen Texas. They even parked 4 of them on our parade grounds when we had a VIP visit.

I do remember something like a heat shimmer coming off them as they warmed up on the ground.

I am sure as they assembled in tight formations at lower altitude before moving up and out that 1000 big bombers would put off some heat and shock waves in the air.

I am afraid that all those I knew who flew or worked on those planes in the war are gone now.

I remember very little of all the things they told me anymore, but it must have been an amazing sight.