You’re tired, hungry, have a cranky baby on your lap and all you want to do is get off the plane, but you can’t because it’s been on the tarmac for hours waiting to take off. While such delays are rare, they can be more common during the hot summer due to thunderstorms and, this year, because of fewer flights to get you to your destination if your flight is canceled. Information is the best ammunition in such situations. Experts advise that passengers be prepared.