Originally Posted by
calypso
(1)Display blanking for a few seconds (no cases at all in operational service in millions of hours). Or a few minutes or until landing
(2)at precisely the wrong moment (must happen at critical phase of flight. Or at any time at cruising altitude. Have you tried flying visually at 41000 feet?
(3) Simultaneously to BOTH PF and PNF displays) and
(4)Simultaneously with a standby systems failure (ever seen standby instruments fail?) Yep, I have.
(5) IMC see (2)
(6) with a pilot who cannot cope (vanishingly small chance ). Some can hardly cope WITH the displays working.
You miss the point - all 6 have to happen at precisely the same time.
Now just calculate the chances even if you put them at low highish probabilities. The probabilities almost certainly meet the required level of safety.
Re 2 - yes I have; there was considerable invective on this board against the crew of AFR447 who lost instruments and were unable to fly for a few seconds without their main instruments - it was felt that any competent pilot should have been able to maintain control. However, you make an excellent case for unmanned commercial aircraft.
