september 11th, extraordinarily sophisticated in its planning and execution and now we are at that point we have the unsophisticated attacks in london with cars started in the west bank and then these very sophisticated attacks being planned allegedly, we learned that now you can't bring laptops on some planes because terrorists are working to hide a bomb in a laptop and take her to an airport that has less than stellar security. >> addressing the aviation domain terrorists are highly interested in that avenue of attack because it is so disruptive. what happened in this instance is we know that bonds and bomb materials are constantly being reviewed, updated and changed and that means our airport security systems whether that is technology or people have to constantly be alert for changes in order to be sent problems.