A commission of inquiry will begin next week to determine how a Department of Defence training exercise sparked a major bushfire in the Blue Mountains.
The inquiry, to begin on Monday, comes after Defence apologised for sparking the fire through an explosives ordinance training exercise on October 16.
A NSW Rural Fire Service investigation found the State Mine fire, near Lithgow, started at the Marrangaroo training area.
The fire burnt through 50,000 hectares and destroyed at least three homes in the Lithgow area.
Retired Sydney judge John O'Meally will oversee the inquiry in Sydney.
Brigadier Jane Spalding and Air Commodore David Steele have been appointed members of the inquiry.
Three Australian Defence Force legal officers have been appointed counsel assisting the inquiry.
The inquiry will investigate how the fire started, conditions at the time and the adequacy of Defence orders, instructions and procedures.
Defence has said the aim was to help prevent a similar occurrence in the future.
Some of the commission of inquiry hearings may be closed in the interests of Defence.
