Talking to a guy who started his career as a stress engineer at MIL, yesterday. Apparently the FBW intro'd in '94 on the Mi-26, which in an earlier form sourced the Mi-12 powertrain, allows 74 degrees of pitch! This allows some incredible rates of climb, and transition accel. I assume he meant unladen, as machine mass is equal to it's payload.
http://www.b-domke.de/AviationImages/Halo.html
It would be interesting to hear from other sources about that rotorhead. The FBW apparently controls the hydraulics through the ECU, rather than bushless DC motor which is more common now. Kindof wishing i had taken that aero stress engineer job myself (although the salary was awful)...
Dave, from your ref i gather the Mi-12 config was chosen as a compromise over tandem to allow STOL at MAUM, by virtue of wings and both rotors in clean air. Tandem would have allowed VTOL, but at reduced MAUM. Not sure why advancing over wings would have helped clearance though, since flapback would be the same with either rotation.
Mart