My ears hurt sometimes on planes, so last time we flew I got both dd and me these nifty ear plugs called "Ear Planes" - they look like corkscrews, and they totally worked, although they felt a little weird. If you can find a child-size set, you may be able to reassure her that they will prevent ear pain.
Even if she hasn't experienced it before, feeling that her worry has been 'taken care of' may help.
Otherwise, as you say, chances are she'll be fine once she's up in the air.
Even if she hasn't experienced it before, feeling that her worry has been 'taken care of' may help.
Otherwise, as you say, chances are she'll be fine once she's up in the air.