The helicopter departed Breeza (south-west of Tamworth) for Northern Sydney on Saturday night, with three people on board.
AMSA Search and Rescue was informed on Monday morning that those on board the twin engine helicopter had not been heard from since it left Breeza on Saturday evening.
AMSA has narrowed the search area down to a 345 square kilometre area, south of Cessnock, NSW.
AMSA’s dedicated search and rescue Dornier 328 plane was tasked for the search, which also involved ten helicopters on Monday.
AMSA’s search and rescue plane will continue to search throughout the night, using its Forward Looking Infra Red (FLIR) technology.
There has been no mayday call or emergency distress beacon signal associated with the helicopter.
AMSA Search and Rescue is setting up a forward field base near Cessnock where the aircraft involved in the search will stage from on Tuesday.
AMSA Media will provide further updates as information becomes available.
Media are advised to follow @AMSA_News on twitter for updates.