The development of aerial firefighting and forestry in southern Australia ran in parallel with the rapid improvements in aircraft technology over the last century. As more advanced and capable aircraft became available firefighters and foresters quickly sought opportunities to utilise and adapt them.
Aircraft have three main advantages over ground resources: speed, access, and observation.
Aircraft have been used for a wide range of tasks including reconnaissance, firebombing, crew transport, aerial ignition, back burning, gathering infrared imagery as well as operational forestry tasks like aerial photography, surveys, spraying, fertilising and seeding.
Much of the early pioneering work in Australia was led by the Forests Commission Victoria in collaboration with other State forestry and fire authorities including the Western Australia Forests Department, Forestry Commission of NSW, Woods and Forest Department of South Australia and Forestry Tasmania. Federal agencies including the CSIRO also contributed significantly.
Overseas forest and fire agencies, particularly the US Forest Service, the US Bureau of Land Management and State agencies such as the California Department of Forestry and Fire Protection (CalFire) as well as the Canadian Forest Service faced similar challenges and proved strong and willing partners in sharing knowledge, equipment and expertise over many decades.
Major bushfires Internationally, southern Australia and particularly the State of Victoria combined with the adjacent States of New South Wales (NSW), South Australia together with the island State of Tasmania, is commonly regarded one of the three landscapes on Earth most prone to damaging bushfires. The other two are southern California and the Mediterranean coast.
Moreover, much of eastern Victoria and alpine parts of NSW are remote, mountainous and inaccessible and bushfires are often caused by multiple lightning strikes which can grow quickly in size. Even with the aid of modern firebombing aircraft to slow the spread of a bushfire, the control of these fires usually remains reliant on ground crews getting to the fire edge to extinguish it completely. Although, heavy rain is sometimes sufficient.
History
Major Victorian bushfires occurred on Black Thursday in 1851, where an estimated 5 million hectares were burnt, followed by another blaze on Red Tuesday in February 1891 in South Gippsland when about 260,000 hectares were burnt, 12 people died, and more than 2,000 buildings were destroyed. This deadly pattern continued with more major fires on Black Sunday on 14 February 1926 which saw the tally rise to sixty lives being lost and widespread damage to farms, homes and forests. On 7 February 1967, the Black Tuesday bushfires in Tasmania were the worst the State had ever experienced, leaving 62 people dead, 900 injured and over seven thousand homeless.
However, when considered in terms of both loss of property and loss of life, the Black Friday bushfires on 13 January 1939 were one of the worst natural disasters to have occurred in Australia and certainly the worst bushfire up to that time. The 1939 Black Friday fires in Victoria burnt 2 million hectares, 69 mills were destroyed, 71 people died, and several towns were entirely obliterated. Only the Ash Wednesday bushfires in Victoria and South Australia in the summer of 1983 and the Black Saturday bushfires in 2009 have resulted in more fatalities.
Bushfires have undoubtedly always been a feature of Australian summers. In an average year, more than 600 bushfires occur in Victoria's National Parks and State Forests which burn about 110,000 hectares and retardant is used on about 10% of these. However, the impacts of bushfires are expected to rise as a result of population pressures and housing growth along the interface between forests and rural communities. Also, while the impacts of global warming are not fully known, Victoria is very likely to experience an increased number of days with extreme fire danger.
Bushfire reconnaissance Experience has consistently shown that early detection and aggressive first attack is the key to keeping bushfires small and gives the best chance for control.Forests Commission, Victoria (1970). Air Operations for Forest Fire Control. In the early part of last century, there was limited road access to the extensive mountain forests, particularly in the remote and uninhabited eastern ranges of Victoria so there was a strong level of enthusiasm for aerial bushfire reconnaissance. While there are differing accounts, it's generally acknowledged that the world's first aerial forest patrol was flown as a demonstration for the US Forest Service on 29 June 1915 at Trout Lake, Wisconsin in a Curtiss Flying Boat by aviation pioneer and wealthy Chicago sportsman Logan “Jack” Vilas. The idea took hold and US Forest Service later joined with the Army Air Service in 1919 to operate regular aerial fire patrols over national forests. However, lack of wireless radios for communication between the pilot and the ground was a major problem and the program paused in 1925.Discussion took place between the Forests Commission Victoria (FCV) and the Air Board as early as 1926, and then over a period of years prior to 1929–30, with the view to commencing regular fire patrols using RAAF aircraft but a lack of safe landing areas proved the main obstacle. Eventually, the first fire spotting aircraft in Victoria was deployed on 18 February 1930Mervin Ellis Bill (1939). Forests Commission Chief Draughtsman; in evidence to the 1939 Victorian Bushfires Royal Commission - near the end of Day 30 (Evidence Transcript - page number 2280). when a RAAF Westland Wapiti from No.1 Squadron operating out of Point Cook near Melbourne flew over the nearby Dandenong Ranges. This is also believed to be an Australian first.
Communications from the aircraft radio were sent in Morse code to the Air Board at RAAF Laverton who then passed the information on to Forests Commission fire controllers. It was claimed that the delay was only a matter of minutes. Over the years effort was focused on more accurately locating fire outbreaks but it was not until the summer of 1939–40 that an aircraft was able to directly communicate by radio with the FCV District Office at Powelltown.
The Royal Commission into the 1939 bushfires conducted by Judge Leonard Edward Bishop Stretton has been described as one of the most significant inquiries in the history of Victorian public administration. Its recommendations led to sweeping changes including stringent regulation of burning and fire safety measures for sawmills, grazing licensees and the general public, the compulsory construction of dugouts at forest sawmills, increasing the forest roads network and firebreaks, construction of forest dams, fire towers and supported further RAAF aerial patrols linked by the Commissions radio network VL3AA to ground observers.
The Forests Commission's communication systems were regarded at the time to be more technicality advanced than the police and the military. These pioneering efforts were directed by Geoff Weste and by 1943–44 direct communication was possible between firefighting crews on the ground using portable, but heavy, RC-16 Radiophones and RAAF aircraft. Although the technology of the portable radios remained primitive and the reception poor unless the user was on a high point somewhere. The HF radio signal was “line-of-sight” and bounced between fire towers and relay transmitters across the mountains back to the district offices.Vintage Radio, By Rodney Champness, siliconchip.com.au, January 2011 In flat mallee desert country of north western Victoria balloons were used in the 1970s to increase radio coverage. Later the introduction of VHF radios, aeronautical radios operating within the airband and then digital mobile phones revolutionised bushfire communications.
By the summer of 1945–46, 114 flights were made with up to eight RAAF aircraft in the air on bad fire days. They operated from RAAF bases at Point Cook, Ballarat, East Sale and Bairnsdale and reported 438 outbreaks. The following year, RAAF Consolidated B-24 Liberators and Avro Lincoln Bombers were made available, supplemented by Avro Anson's and DC3 Dakotas. However, by 1959-60 the use of chartered cheaper flights from private operators in light aircraft became more common and the last RAAF patrol took place in 1963–64. Aerial patrols became common throughout the summer by all forest and fire agencies to supplement the fixed fire tower network.
The Western Australian Forests Department went as far as purchasing four Piper PA18 light aircraft in 1978–79 and employed their own pilots to operate reconnaissance flights in conjunction with private planes.
A major risk to all air fire operations is reduced visibility due to dust, smoke, fog and even low cloud. It was reported as early as 22 March 1945 that visibility was reduced to zero and all RAAF reconnaissance aircraft were grounded with the result that a fire near Toolangi reached a considerable size before being detected.
Mapping
Aerial photography
Aerial photography can be traced back to 1858 but matured during WW1 with the discovery that vertical photos taken with 60% overlap could be used to create a three-dimensional effect when viewed in a stereoscope. Aerial photography was used extensively to map the trenches of the Western Front and in January 1918, General Allenby deployed five Australian pilots from No.1 Squadron AFC on a dangerous mission to photograph 624 square miles in Palestine to update maps of the Turkish positions after the success of the Australian Light Horse at Beersheba and the retaking of the city of Jerusalem. This pioneering use of aerial reconnaissance proved a major aid for the rapidly advancing science of cartography and photogrammetry.
Owen Jones, the young Welsh Chairman of the newly formed Forests Commission Victoria had enlisted as one of Britain's original "Warbirds" in the Royal Flying Corps during WW1 and had long championed the idea of forest surveying, mapping and assessment from aerial photographs so in 1928 the Commission undertook its first major aerial photography project over 15,000 acres of forest. Later, the Tasmanian Forestry Commission undertook Australia's first large scale aerial forest survey in April 1930 when an area of nearly 900 square km (222,000 acres) was photographed in the north-western region by the Air Board. As a result of this initial work, the Commonwealth Government offered in 1933 to conduct an aerial survey of forests in Tasmania at a rate of £10 per square mile or 8 cents/ha including the production of topographic and forest maps. But it wasn't taken up. Needless to say the challenges were formidable for both fledgling forestry organisations including responsibility for vast areas of the rugged, remote country about which little was known. The composite aerial photomosaics were used to produce topographic maps and forest stand mapping.
During the war years, large areas of Victoria were photographed by RAAF aircrews and later used by various state government authorities to produce orthophoto maps. During the war there were a number of military aircraft crashes on State forests. By 1945 aerial photography of 13,000 square miles (3.4 M ha) of the forest was completed, including much of the inaccessible forest in the eastern ranges. The photographs proved invaluable for the design of new road alignments and to map new stands of timber. Accordingly, aircraft were managed within the Forests Commission by the Chief Draftsman, Mervyn Bill.
An interactive map using the 1945 RAAF photography reveals the extent of Melbourne's suburban post-war growth.