sounds like

I heard a  bird that sounded like a soft pneumatic drill along the Greenway inner west Sydney.  I wasn't sure if it was actually a bird at first, I know that bird sounds are so subjective and so its difficult to ID.

I did get a glimpse of the bird, but no distinquishing features, about the size of a Red Wattle Bird.  It is unlikely to be a bird not usually found in suburbia,so i am a bit stumped, perhaps a jjuvenile begging.  Any ideas gratefully received.