Preserving capacity, General Tom Lawson, Chief of the Defence Staff, Keys to Canadian SAR
Issue link: http://vanguardcanada.uberflip.com/i/196923
unManneD sYsTeMs u and other sensors. They can be smaller and lighter since they do not have to cater to having a pilot or crew aboard, and they can manoeuvre without worry of human limitations. Yet as small as the vehicle may be, the system required to support it is quite extensive: communications both to control the vehicle and to receive down-linked data; the ground station which provides the needed direction and control as well as data reception; payload configuration and support; navigation systems; launch and recovery systems; and ground maintenance support including resupply of fuel and consumables. Without this extended system the vehicle will have no real capability. The vehicles themselves vary in size from extremely small, perhaps the size of a small bird, all the way to the size of a modest airliner. Their range and endurance also vary to a similar degree. The smaller versions can be launched by hand or small slings and they can be recovered through parachutes or entrapment devices. On the other hand the larger ones take-off and land on quite conventional runways and are therefore limited by access to such infrastructure. A further model of UAV, in fact one of which has been successfully designed in Canada by Canadair in the 1980s (the CL-227 Peanut), is one powered by rotary wings rather like manned helicopters. These can launch and recover in a vertical manner and are therefore much more flexible in employment, easily adapted to shipborne deployment as well as in forward field locations in support of army commanders. Their range, payload and endurance are naturally limited, much like their piloted equivalent, but their responsiveness and flexibility are impressive. Communications represent a major challenge in developing UAV capability. Extensive two-way communication is vital to the ongoing control and to downloading the sensors' data streams. In practice this means line-of-sight radio connections, which means close proximity to a ground antenna or satellite communications from above. In either case access to sufficient bandwidth to accommodate these needs will be a considerable concern, as will ensuring the continuity and reliability of these communications. Decoying, intercepting and jamming these signals will represent a significant threat, even if it is just from hobby hackers. A very interesting parameter of UAV design is the degree of automation and autonomy afforded to the vehicle. While the words are similar, the concepts are very different. Automation refers to programmed activity which can be foreseen and planned but then executed by computer-directed devices; automation of the required processes can be accomplished both on the UAV and in the ground station. Autonomy, on the other hand, refers to the degree of human direction exercised in the system. In military applications involving delivery of weapons, full human control of the targeting decisions is axiomatic. Where weapons are not involved, in surveillance, for example, much more autonomy can be envisioned. Major fixed wing UAVs are classified by their operating altitudes and endurance. Those able to operate above 50,000 feet over periods of up to 36 hours are called High Altitude Long Endurance (HALE). The U.S. Global Hawk is the prime exemplar of this class; its main role is surveillance, as it can cover wide areas over long periods. Weapons are unlikely to be employed from such altitudes due to inaccuracies from such distances. At somewhat lower altitudes we have Medium Altitude Long Endurance (MALE) UAVs, generally powered by propeller. Altitudes are up to 25,000 feet and endurance about 24 hours; the best-known example in this class is the Predator or its armed variant, the Reaper, which have been widely used in recent conflicts in Afghanistan, Iraq and elsewhere. Most recently Canada has employed the Israeli-designed MALE Heron UAV to support ground commanders in Afghanistan. At shorter ranges and lower altitudes there is a much greater variety of UAVs, such as Desert Hawk, a hand-launched UAV designed to assist the tactical commander to see over the next hill and to patrol his close-in area of interest. A major challenge for UAVs is to demonstrate the required levels of reliability for safety of flight in relation to other users of the airspace. Up until now civilian UAV flights have been authorized by the Canadian Ministry of Transport on an individual basis through the issue of a Special Flight Operation Certificate. Separation of flight has been handled either through a piloted the canadian government has been exploring systems based on hale models, such as global hawk, for applications in our high north, where the need is urgent and the potential for aerospace conflicts is much lower. www.vanguardcanada.com OcTOBer/nOVeMBer 2013 29