Husband has/had a fear of flying, heights in general, and motion sickness. It is a real trifecta of crappiness for air travel. He now has to fly frequently for work. For him part of it was combating the individual things and making the parts he can control as easy/smooth as possible. He takes a motion sickness pill and tries to sit toward the front of the plane (less bumpy helps not only the motion sickness but also lessens the, "OMG something is WRONG" feeling he'd get from even the most minor bumps). He gets an aisle seat if at all possible, asks (politely) to switch if not, and if at the window keeps the shade down (it's really better if he can't see how high he is or that the plane wing is shaking ever so slightly). He also has a noise canceling headphones which has made everything about flying better, makes sure he has media downloaded that will hold his attention, and this year was able to get his job to cover TSA pre-check. This has helped by just making everything feel smoother about the process of getting through security, keeping him more relaxed.
The other thing for him has just been exposure. When you fly all the time, it starts to feel routine even if it still makes you nervous. On a side note, I think at this point he has had enough terrible things happen on his flights (think: plane struck by lightening, plane blown off a runway attempting to land, poor soul passed away from a heart attack while seated directly in front of him, emergency diversion/landing due to heart attack, the list goes on.) that his attitude has just switched too: "well I've survived everything flying has thrown at me so far..."
