Even the 777 has very little in way of mechanical backup (it has a couple of spoilers and the horizontal stabilizer with mechanical linkage). The main differen

Even the 777 has very little in way of mechanical backup (it has a couple of spoilers and the horizontal stabilizer with mechanical linkage). The main difference is the duplicated controls in the cockpit are mechanically interlinked, so moving one will always move both. I believe the 787 is Boeing's first (commercial) aircraft with no mechanical backup, but there's not been much for decades.