A tornado hit Lambert-St.Louis International Airport on Friday evening and caused major damage.  An EF-5 is the biggest kind of tornado, and this one an EF-4.  In fact, it was the biggest tornado to hit the area since 1967.  Luckily, no one was seriously hurt.  But when you see the security footage from inside, it's hard to believe no one was killed.  There's no sound, but you can see things falling from the ceiling, and then about ten seconds of total chaos.