I think the purpose of helicopter thing, which was on the surface just a fun photo op, was to capture aerial footage from many different angles that could then be used to add CGI effects later for dramatic effect, such as the [“falling man”](https://www.thechannelling.co.nz/blog/911-and-the-tarot) which didn’t actually happen. I am almost entirely convinced that there were no people in the towers at the time of their destruction.