I have read the replies, and just wanted to add that even if you have to stop for the trip (stop a few days ahead because breaking the fast properly is more important than fasting properly), you would still be doing the Master-Cleanse for longer than the 10 days that most people set for their goal.
I'm starting another Master-Cleanse tomorrow as well, so we could be online buddies if you like. I have completed 2 fasts that were about 16 days each, and one 21 day fast. I have also started many times but the timing was off, and I didn't make it.
I have regained most of my weight in the last 2 months of horrible eating habits, and am ready mentally to jumpstart my healthy eating again.