In my years in both the manned and unmanned aerial survey environment, I have seen the importance of mapping for the farmer. Farmers rely heavily on this information for planning and management. Some may say that farmers are the first geographic information systems (GIS) users despite them not using computers, fancy software or satellite data. To manage large tracts of land requires planning and data, as it is nearly impossible to tackle such operations as they arise or ad hoc.
Traditionally in South Africa, farming boards such as those in the sugar, timber or maize sectors would supply annual manned surveys of large tracts of land. These would be made available to farmers as paper copies. These very large scale ortho-photos had basic contours drawn over them at 5 m vertical intervals or greater. These surveys come at great expense and take a long time to issue to the end user.
As times have changed, so have economies, and such surveys are often not performed these days. Farmers are increasingly using Google Earth for their planning work as a data source. This comes at a risk since satellite imagery is often not ortho-rectified very accurately and can lead to major inconsistencies. The vertical element is often very coarse and may skip entire valleys via interpolation. Acquisition in rural areas (especially in Africa) is typically years apart, meaning farmers may not necessarily have access to the latest imagery for an area.
Thermal, multispectral and high resolution ortho-photo/contour surveys from manned aircraft are now being used on a private basis. Since the most expensive part of the operation comes from the site establishment, many farmers join together, sharing the costs. But this may still be as much as R90,000 (€5,764.74) for 500 ha.
Unmanned aerial vehicles (UAVs) have challenged the traditional manned aviation sector, specifically for smaller to medium growers. It is typically not feasible to survey over 7,500 ha with an UAV due to its slow flying times and operational altitudes. For those smaller areas, UAVs can and do carry the very same sensors as its full scale counterparts, with much lower deployment costs and turnaround times. They can be transported to reach very remote and difficult places easily and do not require prepared surfaces for take-off or landing.
Data generated from UAVs can be viewed in the very same fashion as historically produced data. GIS maps can be generated or interrogated via GIS software both online and offline or via hard-copies. Tools such as line of sight or profiling are easily available to assist with planning irrigation design or water attenuation areas. Multispectral imaging can assist with spot checks of plant health and offer possible reasons for the lack of growth. Even monitoring of livestock and fencing is now possible for the most modest of budgets. High resolution ortho-photos now allow for individual plants to be identified, which in turn can be automatically counted to assist with densification and yield predictions.
Despite the agronomic industries’ benefit from UAVs, South Africa has arguably the most restrictive regulations in the world for their commercial use. This heavy-handed approach has both forced UAV companies to either operate illegally locally, out of the country to stay in business, or close up shop entirely. The regulations recognise that using UAVs as a tool for agriculture means that they are being used commercially and therefore assumes their use should be governed in the same manner as commercial manned aircraft. This requires UAV operators to comply with a number of steps:
- Hold a remote pilots license (RPL)
- Register aircraft
- Hold an air service license (ASL) from the Department of Transport
- Gain a remote operators certificate (ROC) from South African Civil Aviation Authority
The above is only briefly mentioned and contains a number of sub-steps. The regulations are not possible to comply with as a single business owner and require a large number of positions to be filled, such as Quality Assurance Manager, Flight Operations Manager, Safety Officer, Security Officer, etc. The total cost to comply with the regulations runs over R500,000 (€32,600) and takes over 2 years to complete. Often, some sections such as the ASLs will expire and require renewal before the final ROC is issued.
Since the regulations were published in 2014, only 14 companies may legally operate UAVs with a back log of over 400 applications. Of those 14 legal companies, it is questionable whether any of them can even undertake the specialised requirements that are involved in agricultural work. Agricultural work often involves flying long distances away from the operator, meaning that special dispensation must be made to overcome the legal maximum range of 500 m from the operator. This means that the application of UAVs in agriculture is challenged even more as it is up to the company to prove to the authorities that it can perform such work in a safe manner and have manuals to ensure this safety.
It is unlikely that a small to medium scale farmer would even bother to undergo such an expensive and arduous process. They would be correct in trying to enlist the services of a professional company that specialises in such, but few, if any exist due to the current regulations and this pattern will continue at the current rate of ROC approval.
It has been suggested that the South African Civil Aviation Authority does not have the capacity to fully implement and regulate all proposed UAV operations. This can only become worse as the number of registered (over 500) and personnel (over 400) UAV pilots is ever increasing, putting more pressure on the system to approve such operators. Some feel that it would be best to do away with the ASL, as it would assist in speeding up and simplifying the process. Such has been put into plan in other countries with great success.
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