Sure you do! say your left pitot/static system gets a clog or decides to go CaRaZy! You wouldnt know your airspeed for the approach you're flying. How bout your vaccuum system thinks its time to expire...well gee whiz without a dual vaccuum system once you lose one you've got no suction and no DG or attitude indicator. Then you're sad. sheesh....
By the way good eyes...never noticed that and i spend a fair amount of time flying supplies and troops.
