Originally Posted by
Ahernar
Not going to argue much around this but there are no laws of physics preventing tailles rotor flight . You have to equalise the rotor drag with drag from the body of the aircraft . If this requires 130 rpm , 130 rpm will be necessary ,if that's not humanly pilotable does not mean some autostab will find it impossible too .Most problems will be around oscilations and vibrations in the rotor disk but for an emergency descent it should work
130 rpm (Nr) is well below the normal operating range of modern helicopters. Most run around 275 - 350 or even higher for smaller machines, with a minimum in flight of 90% of that figure for aerodynamic reasons. Going lower would cause the blades to stall and loss of control of the rotor disc.