Originally Posted by
helispotter
Otterotor: Are you saying the flapping consideration is what motivated a swap 'back' to left-hand side tail rotor on the UH-1Y? If so, does that relate specifically to its 4 blade tail rotor? On earlier 2-blade Hueys the flapping clearance would presumably have been same whether tail rotor was on left or right side?
I had read in one discussion that HU-1 / UH-1 tail rotor changed from right to left and back to right over its evolution, but I haven't so far found any photographic or drawing evidence of an initial right hand side placement. Anyone know more?
As for terminology for tail rotor turning direction, I noticed several ways to describe the same thing (including up into main rotor wash) but created yet another description! Twin screw ship propellers are described as being either "inwards over the top" or "outwards over the top" direction of rotation which is fairly unambiguous.
Ray Prouty's books are a good start - yes it makes a difference empirically, but he was struggling to say exactly why, but had some fair "assumptions". Met the man a couple of times and always great conversation and extremely humble. He had time for anyone regardless.
ref: the Bell 205A LHS like a UH-1 to 205A1 RHS those were just 212 parts retrofitted.