By Kristy Gilligan
They are sometimes called unsung heroes, mythical creatures, life savers or just crazy cowboys. Sometimes we laugh at them, other times we beg for them but most times we don’t even notice them. I am talking about those infamous Ag pilots and the amazing aircraft they put to the limits every day.
It’s a special breed who don’t mind flying below the trees, under the power lines and breaking just about every safety precaution an everyday pilot is ever taught. But these guys aren’t everyday pilots. Strange thing is, this group probably contains the most competent and reliable pilots that take to the skies and without their amazing skills and dedication, the whole agricultural industry might come to a screeching halt.
DH 82 Tiger Moths were the first aircraft used in Australia for agricultural operations. They started dusting in 1947, spraying in 1948 and spreading the following year. Modifying what once was a training aircraft basically involved removing the front cockpit and replacing it with a hopper. The Tiger Moth had a mere130hp and had a payload of 33 gallons of spray or 330 pounds of super-phosphate. Due to a high accident rate and low availability of aircraft, eventually the Tiger Moths were replaced in the 1960s by such aircraft as the locally assembled CA28 Ceres and Transavia PL12 Airtruck and the imported Cessna 188, Piper PA 25 Pawnee, DHC-2 Beaver, G-164 Ag Cat, and the Snow Commander S-2D amongst others.
By the late 1970s the US manufactured Air Tractor and Ayres Thrush models were being introduced into Australia. The Air Tractor AT301/2, 401/2, 501/s and 802 model numbering system followed the hopper size in US gallons. The first turbine engine model was the 400, powered by a Pratt and Whitney Canada PT6A-15 Ag engine with a reversible pitch propeller. The AT-502 introduced in the late 1980s is the largest production ag plane in the world powered by a PT 6A-35 Ag turboprop engine of 750hp.
The Ayres Thrush models are descended from the Rockwell Thrush Commander and consist of the Thrush S2R-600; the Bull Thrush and the Turbo Thrush. Another imported aircraft is the Dromader manufactured in Poland by PZL-Miele. The latest Australian ag aircraft is the GA-200 ‘Fatman’ produced by Gippsland Aeronautics at Latrobe Valley, Victoria. There are also several makes and models of helicopters, all imported, used for spraying, spreading and stock mustering. They include the Bell 47 and 206, Hiller 12 E, Hughes 269 and Robinson R-22.
So with all these aircraft getting around and nearly 70 years of history, its easy to see that agricultural aviation is essential to growers and here’s a few reasons why. The use of aerial application means a faster application than ground based methods. It also means a more even application and usually less volume of spray leading to less likely water contamination. In addition, the time and money spent driving machinery across the ground, including extra labor and man hours can be saved while also preventing the damage done by wheels and other ground apparatus.
Crops commonly protected or sewn by aerial application include rice, bananas, cotton, cane, potatoes, fruit and veg. This explains why the aerial ag business is far more prosperous in the wetter areas of northern New South Wales and Queensland than other drought ridden areas down south. There is an aerial ag industry further south, but it is more for application of fertilizer than fungicides or aerial sewing.
When all is quiet there is another role for the aerial ag sector, and that is fire bombing. As if we aren’t already so reliant on this mob, we also need them to provide a source of available aircraft in times of emergency. It’s not cost effective to keep dedicated fire bombers on the ground year around, so the ag industry is called upon to fill their hoppers with fire fighting chemicals and water and fly into one of the most dangerous flying situations to be found. Aircraft are particularly helpful with small fires, such as lightning strikes, when a fast initial response can stop the fire's progress. They can also reach rough and remote terrain to control the fire until ground units arrive. The experience and training of ag pilots is valuable in fire fighting, as is the maneuverability of the plane. Experience in low-level flying, topdressing and flying in less than ideal conditions creates the ideal skill set for fire-bombing work.
Some little known emergency roles of the ag aircraft include locust control, mice and rat baiting, fire ant baiting and oil spill control. Since the late 1970s aircraft have been used to drop dispersants due to their quick deployment and excellent off shore range.
Despite the ‘cowboy’ image sometimes given to the aerial ag sector, it’s suprising to find how well regulated and precise it really is. Operating high powered aircraft loaded with dangerous chemicals is no joke, and every operator must meet strict regulations, not only from CASA but also chemical authorities. The Aerial Agricultural Association of Australia (AAAA) provides lobbying and support to operators and assists CASA in the management of the industry. The AAAA are holders of an industry standard Ops Manual which meets the new CAR 137, to which all fixed wing aerial ag operators must be compliant by May 26th this year. The association also assists their members in meeting regulatory requirements while maintaining flourishing businesses.
Gone are the days of accidentally dusting a neighboring paddock. Today the industry is more reliable than ever with the use of GPS for mapping application. Once requiring little men with flags to run around as ground markers, using GPS a pilot can punch in the key points of the field's layout and the swath width required and leaves it to the computer to indicate when the pilot should position the aircraft to carry out the spraying within centimetre accuracy. The same course can be flown over and over again with sub-metre accuracy - that is, less than one metre's difference in the flying course no matter how much time passes between flights.
GPS also allows for accurate mapping of paddock shapes, hugely improving the accuracy of spraying and the productivity of the crop involved. Furthermore, data logging through GPS has allowed pilots to prove what was sprayed, where it was distributed and what the prevailing wind conditions were at the time of spraying, making it easier for the farmer on the ground to be convinced he was not over charged and got a good application.
Agricultural aircraft pilots are not cowboys but are in fact highly trained and licensed, and can only be described as professionals. To obtain an ag rating a pilot must first have a commercial pilots license and then attend a school approved and supervised by CASA for an intensive agricultural flying and theory course.
Following the course and the appropriate flying and written examinations that all us pilots adore, a pilot is issued with an Agricultural Class 2 Rating. During the initial introduction to the industry, he operates under the supervision of a CASA approved Chief Pilot. After a total 1,000 agricultural flying hours, he is again examined (argh!) and issued with an Agricultural Class 1 Rating. All States require pilots to hold an Agricultural Chemical License or Rating. This involves a Spraysafe examination conducted by the AAAA and accepted by the regulatory authorities such as Primary Industries & Environment.
By lifting a little of the mystery surrounding this industry and its operators, hopefully the term cowboy can be kept for a man on a wild horse in the future. And while the business of aerial agriculture may be down and dirty, it is only through great people, exceptional aircraft and the wonder of technology that we continue to rely on it today. In the future I hope to speak to more ag operators and learn more about the challenges they face I our very volatile aviation industry. To date I have found them to be the most accessible and easy going of all the aviation sectors to deal with. Perhaps that has got to do with being able to deal with everyday people who live on the land.
