But wait, there's more... MEs do up automotive to a typical x2 safety factor. Aviation, doesn't like excess weight, and does it up around x1.2 to x1.4, except for really critical areas (wing spar) and that might be x2. Redundant in aircraft? Youbetchya, most stuff is triple redundant, and some double failure monitored. One system down means go home. Two systems down means land immediately. There's just no place to pull over if something breaks down. Beefier no, stronger, yes. Using exotic alloys and materials. Automotive would do that also, but no one would be able to afford it.