New Royal Australian Air Force (RAAF) overland military flying training area airspace across the state became active on Thursday, November 30.
A Department of Defence spokesperson said the new North West NSW military airspace replaced the current Williamtown Western Airspace.
The spokesperson said the new airspace boundary extended from Carinda and Walgett in the west to Bellata in the east, and south to Gunnedah, Gilgandra, Mudgee and Scone.
"The RAAF requires improved restricted areas to support its Hawk and new Joint Strike Fighter (JSF) aircraft training operations," the spokesperson said.
"Airservices supports this change by providing new and amended routes that will allow the movement of civilian aircraft to go around the restricted areas when they are active.
"The North West airspace design process prioritises the safety of flight for military and civilian aircraft operating within and near the airspace.
"It will also deliver efficient air route access into and out of Western Sydney Airport, while considering environmental and community requirements, aviation industry requirements and RAAF flying training outcomes."
Visit the Royal Australian Airforce website, airforce.gov.au for further details about flying airspace.