Why do accidents still happen? Well, taking Tarnished's "45.7% of statistics are made up on the spot!" (almost), around 80% of military aircraft accidents are caused by human error. But, as illustrated, we need aircraft to operate military aircraft in an operational environment. So, while we can continue to push technology to make unstable aircraft flyable etc etc, and continue to try and make systems safer, the biggest risk area is still putting someone in the cockpit, and its is a risk are that engineers will continually strive to reduce. But it is a risk 'we' (society, our lords and masters and above all, military aircrew) are prepared to take. When societal perceptions change, that's when you'll see unmaned airliners. But the military will still want the man in the loop.
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