Get a case with a screen protector built in. I'd get an Otterbox Defender at this point, but when I bought my case that wasn't available yet. So I've been using this one combined with some separate rubber grips (probably wouldn't be necessary for the Otterbox).

You're gonna want some kind of rugged-ish case. After 1,000+ hours flying small planes, you're gonna drop your iPad at least a few times. Mine has fallen or been knocked off the wing by the door probably five times.