The formulation to account for effects of propeller angle of attack on
acoustic radiation by propellers is presented. A propeller operating
at an angle of attack presents a nonuniform inflow situation that is k
nown to have a pronounced influence on noise, Noise predictions, based
on this new formulation, are compared with measured wind-tunnel data,
Predictions for observers fixed in the propeller plane are also inclu
ded to assess the influence of shaft angle of attack.