The New Zealand Agricultural Aviation Association conference was held in Nelson this year focusing on the theme of an industry revitalised. The president of the NZAAA John Sinclair was quick to point out however that insurance for agricultural aviators has risen 120% because of the disaster in New York. "And they are talking it could go up 3-400%, so the prices have to go up, you can't absorb that," he said.
Despite this, the industry is booming and John explained that two years ago they were trying to find overseas homes for 30-40 old agricultural planes to try and rationalise an industry with too many planes. "Now we could do with 30-40 more. Farmers are having a good time out there at present - and so are we."
Two innovations highlighted at the conference of clear benefit to farmers were advances in differential GPS systems, and the new through valve spray boom (TVB™).
Differential GPS systems have been developed that control hopper doors, allowing them to be automatically adjusted as the ground speed of the aircraft varies, going up hill, down hill, into wind or down wind, and keeping a constant flow. Most work today is done using GPS from which printouts can be produced for farmers, and on display were new systems that can print that information directly onto computer generated 1-50,000 topographical maps of the clients farms, clearly painted with where product has been applied.
John Sinclair was also a speaker at the conference, sharing with the attendees his own first hand assessment of the TVB™ spray system. He noted this was not a new innovation, as he had seen a picture of one working on a Bell 47 helicopter spraying strips in regenerating forests in the late 80's, but it has only recently become commercially available - at least in this part of the world. "We bought one after the conference last year and have been using it on a Jetranger and I've got to tell you it is an awesome bit of kit," he enthused.
The TVB™ is a precision application spray boom that enables the agricultural industry to apply herbicides, insecticides and plant growth regulators accurately, uniformly and safely. Developed to enable fixed wing operators to apply herbicides quickly and accurately, it is now available for helicopters and it produces large droplets, free of aerosols or fines, at speeds up to 55 knots according to Mr. Sinclair. Optimum spray swaths are achieved at heights of more than 70 to 100 feet above the target, greatly reducing the stress on pilot and machinery. Noting that earlier trials in New Zealand with big droplets showed poor coverage, it has been the advent of organo-silicon penetrants that make the difference now with big droplets having a low surface tension and shattering on impact with the target.
"We believe we are getting 30-40% more chemical onto the target using this gear," John said. "In fact there is a strong argument to reduce chemical rates. We do all our spraying with this boom including spot spraying from the hover, and high volume gorse spraying with Answer. We tested it in a 7 knot crosswind and with a release height of 100 feet we found that the entire swath was displaced 10 metres downwind, but 2 metres beyond that, there was no spray collected at all."
In Marlborough and elsewhere, where vineyards, lifestyle blocks and forestry share common boundaries this is a significant advance. "We can spray right up to sensitive boundaries without worrying about the normal buffer zones. Even when the wind is blowing towards the sensitive boundary it is safe to spray although in this situation we do keep the height down to 50 feet."
By the time the system was fitted it had cost $77,000 NZ but the improved productivity will see that recovered in 12 months. The swath width has increased 20% and it has bought in more work, meeting the environmental expectations of the large forestry companies. Because it can be used in the wind there are more and longer spraying windows, and with less need to contour fly it is easier on the helicopter offering enormous safety benefits for the pilot as the spraying height is above most of the wires and other obstacles. And as John summed up his assessment, "all this impacts on the bottom line".
