I never cease to be amazed at the first moment when an airplane feels like a kite in the wind right after takeoff.
Rather, what makes me uncomfortable, is that sometimes very important parts of the plane blow up and the engineers can't figure out why. But hey, at least there are two or four engines and three or more power supplies.
I'm anxious because I'm very high up in a small tin can and can't get down.
It doesn't give me much confidence in the quality controls of flying, but the fear mindset is much more insidious - and more importantly - in my own personal control. Whenever that mindset kicks in, I joke to myself that life has been good to me, and usually that takes care of things...
On the flip side, I sat next to a woman who had taken two Xanax and drank two screwdrivers during a three hour flight, and still gripped my hand (a complete stranger) during landing.