pteen times it can be repeated and it's still beyond any comprehension. While it is so simple. A truss is falling down and there's a moment when it is on a right height and then it stops and is not falling down any more. It's enough to count the upheaval momentum. When it is already known, then it's enough to be in the right moment in the right place. Everybody knows that it's too late after, while it's too early before.

But where is this truss falling down from?
Yes. That's right – where is it falling down from?