Backburning to build or thicken a control line from a strategic fuel break, road, ridgeline or 4WD track is a common and effective dry firefighting technique, particularly in remote and rugged country.
But indirect attack using backburning increases overall fire size and therefore fire perimeter. It also introduces more fire into the landscape, often under unfavourable fire weather conditions.
Backburning is often done in conjunction with aerial ignition and burning out the remaining fuels.
However, backburning ahead of a fast-moving fire front is often a last resort strategy, one that requires great skill and courage, as well as a generous dollop of good fortune to execute successfully, which presents a serious dilemma for all forest firefighters.
Backburning operations can be a spectacular success at stopping the run of bushfire, but many a backburn has either got away or split the main fire to create a troublesome second fire front.
It also should be noted that there is a huge difference between Fuel Reduction Burning (FRB) which is done in the cooler months, under prescribed weather and fuel conditions and within a predefined boundary, compared to a backburn constructed as a control line (often under difficult fire weather conditions and with limited time to plan and prepare), to stop the passage of a running bushfire.
Victoria’s Forests & Bushfire Heritage 