Inside the Tower; Unmanned; Wonder of the World | 60 Minutes Full Episodes [0:00-1:49]

Last year's collision of a passenger jet and Army helicopter in Washington, D.C. killed 67 people. For the first time, you will hear from an air traffic controller who worked inside the tower. Was there pressure to get more planes in that house? And what we discovered about continuing problems at that airport. Why do we always have to wait? Until people die to take action. Forget everything you think you know about warfare. The traditional front line in Ukraine has expanded to a 10 mile wide swath where anyone spotted by a drone can be hunted down. Tonight, lessons from Ukraine's kill zone. Excellent, Scott, that's really good. Nothing could prepare us for the majesty of the largest cave passage on earth. Sky scrapers would fit in here. A 747 could fly through. Maybe most remarkable, all of this was discovered only recently. And there aren't a lot of places on earth that you can discover for the very first time. You have to look pretty hard for them. I'm Leslie Stahl. I'm Bill Whittaker. I'm Anderson Cooper. I'm Sharon Alfonci. I'm John Wertheim. I'm Cecilia Vega. I'm Scott Pelley. Those stories and in our last minute, a final four legend has a game plan for America. Coach Mike Shoshesky, tonight on 60 minutes.