The guys who make the belt-based camera "bag" that I use have released a free pdf titled "Fear For Your Gear" which gives you tons of tips for surviving airline travel with your camera gear. I contributed a tiny bit to Part II of the article. The tips have nothing to do with their bags and are useful for anyone who travels with camera gear.
I’ve been using their Airport International bag (shown above) for all my flights lately and I really like the way it’s setup. The bag is sized to be legal carry-on size for domestic and international travel and I’ve had it on all sorts of planes including the ones that only have one seat on each side of the isle and have have never had to check it. It comes with a security cable that I use to lock the back to stuff at airports, hotels and other locations and a TSA approved combo lock for the main compartment. It also has a great pocket on the front that is designed to handle their Artificial Intelligence laptop case, which makes for fast and easy security checks at the airport since I can have my laptop out in about five seconds and back zipped up in the bag in less than 10 seconds (the laptop bag can even fit inside if you order the low divider set, which I use when traveling internationally). I pack the belt-based system into this bag and then leave the bag in the hotel room or car when I’m out shooting (since all my gear is on my belt). I discussed the exact belt components I use in an earlier post.
If you ever end up purchasing any of their products, be sure to do it by visiting this special page and enter code WS-055 so you can get a free item if you end up spending more than $50.