I was rereading the last update to the rule book and I noticed this on page 8:

"A ship cannot perform a barrel roll if this would cause
its base to overlap another ship or obstacle token. The
player may measure to see if his ship can perform
a barrel roll before committing to this action."

My question is at what point has the player committed to the barrel roll action?

Under the competitive rules, when he measures and discovers it will fit. If it doesn't fit, there's no penalty, and the player can choose a different direction, or perhaps a different action.

As Parravon says, under the tournament rules you have to announce your direction before measuring and you are commited to that if it results in a legal action. In non tournament rules, I think you are only actual commited once you actually move the ship.

I'm looking in the Tournament FAQ and I can't seem to find it. Anyone have a page for it?

It's actually in the regular FAQ, but in the section on competitive play, page 9 first column

thanks