Old 16th Nov 2018, 15:17
  #796 (permalink)  
chopjock
 
Join Date: Nov 2008
Location: UK
Age: 61
Posts: 901
Twin tail rotors would simply be two shafts running down the tail boom, each driving a tail rotor, so there would be one rotor on each side of the tail boom instead of just one on one side.
And contra rotating, it's not difficult to do, I designed and built one for a ROV. It worked great when one of the gearboxes failed...
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