We all know that after the "9/11" tragedy this game received some changes and one of them confirmed to be a "cut" to the DeaDodo's flying path. It was heavily shortened to avoid DeadDodo to fly around the skyscrapers.
Thankfully, developers forgot to replace these paths in the first ever PS2 PAL release (1.40). If you wonder, shortly after, Rockstar released a new PAL version (1.60) where this bug was fixed. (Both of these versions were available starting from day one.)
Thanks to this, we can take these paths from the first ever PAl release and use them on PC and see where it was meant to fly if the tragedy wouldn't have happened.