One-element vs two-element design

Sat Jan 17 23:23:42 UTC 2004

> This is why commercial airliners have multiple engines even though the
> system is less reliable overall than a well designed single engine craft
> the failure of a single component does not entail the catastrophic failure
> of the entire system.  (there are exceptions to this but the overall
> concept does work).

Last year, a Boeing in flight over the middle of the pacific ocean had 
its entire glass cockpit system go dark.  After frantic conversation 
with the air traffic controllers a decision was made to toggle the 
circuit breakers for the TRIPLE-REDUNDANT computer system onboard, which 
brought back the displays.  Even with a 2+1 setup, things can still go 
wrong...