James,

I have to agree with the majority here. Having flown into several North American cities from London, my advice would be to wear an all-leather sporran on a strap, not a chain - you want to reduce the amount of metal you are wearing as much as possible. For security reasons, pack your sgian dubh and kilt pin in your checked-in luggage - don't try to carry either of these items on the plane yourself as they will almost certainly be confiscated.

For sheer comfort during the long flight, I personally opt for a Utilikilt rather than a pleated tartan kilt. Aircraft seats are notoriously cramped and narrow making it almost impossible to get your pleats arranged correctly. With a Utilikilt (other utility kilts ARE available!!) there is far less fabric to sit on and it doesn't matter quite so much if you arrive creased in all the wrong places, which you will after 8 or 9 hours flying time. Such kilts also have capacious pockets, alleviating the need for a sporran.

Oooops! Having written all of that, I realise that you did not say you will be travelling kilted, but I hope you will be!