I think the main problem with aircraft is lack of redundancy. They still count on the ability of letting the pilots control the aircraft (e.g. .1% of the time as you mentioned), I think they should just try to go all the way as much as possible. For example, if they had 4 redundant pilot tubes on different places and other redundant methods to measure altitude and airspeed the AP would never have disengaged. For a large plane those sensors are basically free, and it&#x27;s very easy to tell whether they&#x27;re working correctly by cross-verification&#x2F;calibration (i.e. maintenance&#x2F;reliability is easy) -- they just don&#x27;t go all the way because they&#x27;re still on the paradigm that &quot;well if a couple pilot tubes and&#x2F;or other systems fail we can just hand it to the pilot&quot;.