Investigations after fatal NSW plane crash

A pilot has died in an ultralight plane crash in a semi-rural area of Sydney's southwest.

Police are treating the discovery of human remains near Taree as suspicious. Source: AAP

Recreational Aviation Australia is to investigate why an ultralight plane plunged to earth, killing the male pilot in Sydney's southwest.

The man died when the craft struck the ground at Oakdale about 4.20pm on Friday, a Civil Aviation Safety Authority spokesman told AAP.

Investigators initially thought the plane, which crashed about six kilometres from the The Oaks Airfield, was a Drifter but later realised it was a Fisher Mark 1, the spokesman said.