I'm with A and C
Are you (LowNSlow) saying that the pressure from my hand is going to puncture through the steel spar? Or is the total load on the spar more than there normally would be?
AC-DC
I thought the ribs were to keep the skin from being sucked out by the low pressure. As such they aren't the main load bearing members because they transfer their force onto the spar for transmission to the fuselage. That's what I thought anyway.
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Confident, cocky, lazy, dead.