About a quarter century ago, my wife and I were flying out of Moscow on our way to London. We somehow scored seats 1A and 1B on a big British Airways jet and after a month in Mother Russia, well, we had "wound down" on some pretty good stuff as we approached the Baltic.
On board were, of all things, a group of Germans who were the offspring of German families caught up in WWII and living in Siberian villages until even the Russians grew tired of them and let them out. Germany wouldn't take them. England would. The pilot announced we were just about out of Russian airspace and there was a big cheer and British Airways treated the whole lot of them to some pretty decent hooch.
I looked out the window to see what I could see, prompted by the announcement and whooosh, a Lufthansa jet seemed to pass by about a foot away. It was actually pretty scary....I think I could see the rivets in the wing. I mentioned this to the attendant who went into the cockpit and soon came back and asked if I would like to join the pilots for a bit and talk about it. I had some diplomatic status but nothing like this, so, martini in hand, up I went.
Seems as just about the instant when Moscow air traffic control is about to hand off to Tallinn, Estonia and radio contact is switched off or over, the pilots of oncoming planes liked to scare the Russian controllers half to death and "stage" a close call. 1,000 feet not 100 like it seemed, but on radar, it looked like a smash sure to happen.
It puts Ukraine into some context.