Two things:

1. As I understand it, most turbulence is annoying. Only the most extreme is dangerous. I have flown into thunderstorms across oceans, been hit by lightening, and had the plane plummet. Although those are frightening for the passenger, the pilots seem to take it as part of the flight and it's forgotten before they land.

2. The fear/anxiety is from the motion. There is data to support that the abrupt changes in orientation affect the inner ear and that is the cause of the panic.

With these things in mind, you can feel safe flying and if alarmed remember that this can be a normal response. Some people enjoy riding a roller coaster because of the thrill of vestibular stimulation. Others may not, but that does not mean that the over stimulation is dangerous. It's best to distract yourself with other auditory input. I discovered how enjoyable the movie Top Gun was while on a coast to coast flight during the summer thunderstorm season.

Also, planes are very noisy and affect the auditory circuit, cause fatigue, and hence can overstimulate you. I find wearing ear plugs, headphones, or noise canceling earphones to be a big help.

I used to be terribly afraid of flying and now I find that I fall asleep before takeoff and then wake up after the plane has leveled off. No more tranquilizers for me through the use of understanding airplane safety, and how to combat the negative effects of overstimulating the inner ear.