I shoot medium format (6x7cm), and this gives me an advantage over 35mm shooters for one simple reason: Each 120 or 220 roll of film has an inner plastic core around which the film is rolled. There's no metal. This means that I can stuff my pockets with film and walk through the metal detector - bypassing the X-ray machine - without being hassled.
I make sure that all metal objects, such as coins and keys, are out of my pockets and that I'm not wearing a metal belt buckle and my shoes don't have any hooks or supports that contain metal.
When I wear six-pocket pants and a shirt with two large breast pockets, I can carry 80 rolls of 220 film. It's a bit comical, but it works. Inside the plane, I then put all the film back into my camera backpack - or, if I must make a connecting flight, I use the air sickness bag to dump my film so I'm comfortable in the seat. Then, before deplaning, I load up again.
For 35mm shooters, I'd suggest the following. The next time you walk through a metal detector, put five rolls of film in your pocket. Take them out of the box and out of the plastic container. See what the reaction is on the part of security. If they simply see that you have film and pass you through, you'll know that you can increase the number of rolls in the future. If they insist that you put the film through the X-ray machine, you'll know this tactic doesn't work.
If you are seriously concerned and don't want to stress yourself at the airport, you can Fed-X the film to the first hotel on the itinerary a few days ahead of your departure. You can then call the hotel to make sure it arrived. It has been my experience that Fed-X, DHL and UPS won't tell you whether or not their parcels are X-rayed. However, it just doesn't make sense that they would do this.
When returning, you can send your film to your home or a photo lab using one of the overnight couriers and again avoid the unpleasantries at check-in.
Article by Jim Zuckerman. To learn more about photography, explore the many online photography and Photoshop classes offered here at BetterPhoto.com.