The noise of a pusher-propeller was tested. The noise frequency spectrum characteristics of propeller at different revolution speeds with fixed pitch were obtained to research the noise level varying with revolution speed and pitch. The directivity characteristics at typical operating condition were also tested to get the directivity of tone noise
broadband noise and overall noise. The results showed that as the revolution speed and pitch increased
the contribution of broadband noise to overall noise increased. The broadband noise was comparable with the tone noise at large pitch and high revolution speed. The directivity of broadband noise agreed with the characteristics of blade self-noise. It is probable that the broadband noise is dominated by blade self-noise.