According to sources I've read online, Tom went on a hundred H.A.L.O. drops including extensive training in wind tunnels and other kinds of skydiving to prepare for the one stunt that you see in the trailer to the movie. It was so dangerous, that Tom Cruise prevented Henry Cavill from participating. He cited something like, "You would get the rest of us killed because there are things I need to do in the air that you are not trained for." Holy crap.
Tom Cruise actually broke his leg leaping what looks like a huge gap between actual buildings. He learned how to fly a helicopter, and he and Cavill (in helicopters) were actually four feet from each other's rotors and at points, less than that from an actual cliff in New Zealand (filming the Kashmir sequence). Cavill said that one mistake, and they would both be dead.
There's another stunt in the film where Cruise climbs a rope that's connected to a payload beneath a helicopter. This was absolutely real, and the helicopter is flying through the air. Cruise falls and catches the netting. It was a planned stunt, but the people on the ground didn't know that was going to happen and actually thought for a few moments that Cruise had just fallen to his death. Of course, Cruise just climbs the rope again and gets into the helicopter.
Look...again I'm no fan of this guy's real life work. I think he belongs to a cult that worships him like a god. But there are parts of my brain that think...hey, maybe he is one. A demigod at least. It's absolutely insane what he does to make these movies. In comparison, I had a piece of siding come loose on my house that needed to be snapped into place, and I was terrified to get up onto my roof so that I could fix it, and I'm ten years younger.
When I suggested to the collective mind of my Dungeons and Dragons group that Tom Cruise is the new "Chuck Norris" as in the whole "Chuck Norris" meme that went wild online about a decade ago, they all shot it down. My friend Matt said, "Tom got his start in movies by just being pretty. Chuck Norris had actual talent."
Eh...that may be completely true. But at 56, it's hard to argue that Tom Cruise is not doing things that put anything Chuck Norris ever did to complete shame.