Calculate Main Rotor Downwash
With the advance ratio components evaluated, the main rotor downwash can now be calculated using the iterative technique described in an earlier chapter:
A good starting value, for the iteration, is that for hover, namely:
Ai OLD — 2^/~Ct
This now determines the downwash AiM.
A.3.1.3 Assemble Main Rotor Powers
The main rotor power components can now be calculated. Induced (note that the induced power factor kiM is included):
PiM = kiM • Tm • VTM • ^iM
PpARAM = D • V
Summing for the total:
Ptot M = PiM + Ppm + Pparam
A.3.2 Tail Rotor
The main rotor torque is now obtained from the total main rotor power, from which the tail rotor thrust value necessary for torque balance is calculated.