It happened decades ago. Unwad your panties.
And no, it's not particularly dangerous. I've been on job sites where heavy equipment was lifted over rooftops. As long as a certified operator is running the equipment, it's safe enough.
If it was incredibly dangerous, those of us that sat in grand-dad's lap while he drove, and learned to drive like that would all be dead.
Lord, I dislike sissies.
/johnny
I've seen pictures of a suburban home with it's attic sliced clean through to the eves and a crane boom still laid out nearly horizontal. the crane itself was standing on two outriggers with the base plate near 70° out of plumb. I assume the operator was a pro but you need more counterweights when you lift over the side, oops!
I also saw a real life mobile hydraulic crane laying on it's side with the boom helplessly laying out horizontal. It was a brand spanking new model and was rolled out for a promotional photo shoot with the CEO and the Chief Engineer in attendance. The professional operator just extended the boom out with a modest load and forgot to set his outriggers. I know the operator was a pro because he worked for the company that built the machine. The "accident" happened in the company parking lot (SE Pennsylvania). They had to bring in another crane to stand it back up again!
Then of course there was the crane disaster with the 15,000 ton mobile crane lifting sections of the movable roof for Miller Park Stadium in Milwaukee. Big Blue collapsed with a load of 450 tons on the hook. Three people were killed, several injured and millions of dollars in damage and lost time. The "accident" was blamed on side wind loading. The entire job was staffed by a steel erection firm and it still managed to collapse.
The best advice is to have a care where you stand when there is high steeel flying overhead.
Regards,
GtG