I will be traveling from the United States to Eastern Europe on Tisha B'av. When the sun sets after I arrive, it will be much less than 24 hours after the sun sets in the states that I'm leaving. Other than changing the day of my travel, how should I time my fast? Thanks!
There are reasons not to travel on Tisha B'av. For one, you shouldn't occupying yourself with matters which divert your attention from the sense of mourning for the destruction of Jerusalem.
However, if you do fly, you fast according to local time. That is, you go according to the time wherever you are. So if you travel from west to east you will indeed have a short fast.