Can I ask a basic question as someone who doesn't know too much about helicopter technology please.
I understand why a conventional helicopter requires a tail rotor - to counteract the natural tendency of the body of the helicopter to try and rotate in oppositional/sympathy with the overhead rotors. I can understand that having two outboard propellors could achieve the same function of a single tail rotor.
But what would happen of one of the two outboard propellers suffered a fault and stopped turning. It would seem to me this could lead to some difficulty with counteracting the natural turning action of the helicopter body as described above.
I'd be grateful for a simple answer using layman's language. Thank you.