While most current peacekeeping missions take place in wide areas that are sparsely populated--Iraqi and Afghanistan population densities are respectively 62 and 49 inhabitants/[metre.sup.2] compared to the 115 and 277 of France and Great Britain--most contacts with insurgents still take place in urban areas. Although in Afghanistan 'urban' does not necessarily mean highly built-up areas, the typical mud-built compounds of that nation are intricate enough to generate problems to allied troops, as an adequate level of situational awareness is certainly more difficult to achieve there than on open ground.
The denser the urban scenario, the weaker the level of communications, not to mention that of automatic location systems. Opening breaches to avoid booby traps often installed by insurgents on the most obvious entrance points is another problem, and identifying enemy firing positions adds to the burden. Own movement also becomes a problem in urban areas, especially when more densely populated, and the fact that armed elements can easily merge within the population renders the situation even more hazardous. The irony is that while urban terrain is certainly one of the worst places in which to engage insurgents, it also is where they are most likely to be found--and this alone commands the development and acquisition of ad hoc equipment.
Vertical Awareness
What is better than having a top view of the area in which one is called to operate? An image taken from an adequate height can provide a map that evolves in real time, provided the troops on the ground have the right equipment to receive that imagery. Generically this is known as the Rover, the latest version of which--the Rover 5--is no bigger than a Playstation. Any top observation used to co-ordinate movement on the ground must be available in strict real time. What happened in October 1993 in Mogadishu is still a scorching experience, as a good share of the tragedy was imputable to the delay that occurred between the observation made by the aircraft overflying the area and the reception of the message by the troops on the ground.
The use of large and persistent drone systems over an area of operation is also questionable in this respect. To start with, their numbers are limited, and the amount of tasks they are assigned leaves just a lean portion of their flight time to support ground troops. These valuable systems are normally deployed when major operations are being planned or underway, mainly to provide intelligence before the action and allow upper-echelon commanders to monitor operations in real time. However, when small units are engaged in daily patrols these are not available.
Many armies have acquired much smaller and cheaper systems that allow them to survey their next area of operation themselves before sending in troops. In Afghanistan, platoon or company-level operations are often carried out in isolated villages where troops operate together with Afghan security forces to guarantee security and provide assistance. We normally deploy at night close to the village, and at first light of dawn we launch a Raven before sending the commander of the Afghan forces detachment to talk to the village elders, an Italian officer told Armada.
The Aerovironment Raven is operated by Italy (and many other countries), with each company of its 41st Regiment running its own systems. However, organisational plans for future medium infantry regiments have provision for deployment of three vertilift systems within the regiment itself, leaving the operation of tactical drones and other higher-end assets to specialists.
The current 1.9-kilo RQ-11B model provides endurance between 80 and 110 minutes with single-use batteries. Hand-launched, its operational range is about ten km, which provides a wide-enough radius, as areas to be investigated under those circumstances are usually much closer, and the drone provides more than one hour of over-target time. With two air vehicles overlapping their missions, surveillance time can be stretched, but within limits. The US Armed Forces have recently signed a contract to upgrade the Ravens to full digital configuration, which will provide greater communication security and better performance.
Aerovironment's ruggedised ground control station is also Playstation-sized and weighs 3.37 kg. Not only does it allow one to store multiple pre-planned missions and follow the video images in real time, it also provides for the capture and storage of up to 80 still images taken from the video stream. The station is common to all Aerovironment mini and micro drones and is thus also deployed by the US Marine Corps to operate the Raven, Wasp III and Dragon Eye drones.
Even smaller than the Raven, the 430-gram Wasp III has a 72-cm wingspan and a 45-minute endurance, while the twin-engine 2.7-kilo Dragon Eye has a 1.1-metre wingspan and an endurance of 45 to 60 minutes.
British forces are using the Lockheed Martin Desert Hawk III that was acquired under an urgent operational requirement. It can be equipped with three different payloads, namely a daylight stabilised turret, a thermal or low-light side-looking camera and a low-light illuminator. Tipping the scales at four kilos, the 1.37-metre wingspan Desert Hawk III has a 90-minute endurance and a 15-km operational range.
Another battle-proven mini drone is the Israeli Elbit Systems Skylark I, which is also operated by at least ten other countries. Amongst these, Australia, the Netherlands and Canada have deployed them in Afghanistan and in Iraq. Weighing 4.5 kg with daylight sensors and 4.8 kg with night sensors, the Skylark I has a 90-minute endurance, a wingspan of two metres and is carried in a backpack together with the PC-based control station. A larger and longer-endurance version of the Skylark appropriately suffixed LE was launched in late 2008 and can remain aloft for three hours.
The Bundeswehr and the Dutch forces field the Aladin built by EMT in Germany. With a take-off weight of less than four kilos and a wingspan of 1.46 metres, it offers a one-hour endurance and boasts four daylight cameras: one is used for pilot purposes, two are pointed downwards (one for wide angle and the other for close-up viewing), while the fourth is canted sideways for circling observation mode. Two forward-looking cameras, one thermal and one colour daylight, constitute the night package.
This pretty much rounds up the list of fixed-wing micro and mini drones most widely used in the sub-Asian continent, although the range is widening. Hand-launched, with control stations averaging from compact and light to relatively light with the latter offering a longer range and thus a more powerful datalink, these systems allow troops to work out their own risk assessment from real-time imaging before entering a built-up area. Plug-and-play payloads allow to easily switch from night to day sensors, adapting the air vehicle to the situation, particularly when the urban configuration consists of low, three-level buildings, such as those typical of current theatres of operation.
What these systems cannot provide, because their aerodynamic lift requires them to fly at a certain speed, is continuous target observation, and are thus more to be considered small-area surveillance tools rather than target surveillance systems. Although target surveillance could partially be achieved by circling around the point of interest, endurance limitations would soon cut in, not to mention that an urban configuration can easily deny viewing the target under some angles given the drone's relatively low height above the ground and that while electric motors are relatively quiet the presence of a continuously circling drone would certainly not remain unnoticed for long by the locals.
Not yet used in large numbers, vertilift micro and mini drones are certainly those that can best fill that type of operational requirement. The typical drawback of rotary-wing aircraft is their limited endurance, especially when they are required to hover for long periods of time. In addition, while their noise signature still makes them easier to spot, they are also easy targets when they fly at low speeds or hover. However, where a vertilift system has an edge over its fixed-winged counterpart because of the fact that it can land on a vantage viewing spot, slow down (and even shut down) its engine and remain in position as long as its power source allows, then whoop up the engine, take off to reach another observation position or return to launching point. What it will do once landed in a technique known as 'perching' is up to its payload and to its operator's needs.
A typical payload package will include imagery sensors in the form of day or night television cameras to provide realtime footage to the ground control station; power guzzlers here are more the datalink than the sensors themselves, but change-detection software may well help in the quest to save energy by allowing the system to broadcast the imagery back to base only when something is moving within the scene being observed by the camera, although this will require an onboard image processing system that could certainly add weight to the sensor package. If and when costs are no longer an issue, one could also envisage using the vertilift drone to place a sensor at the right location and then leave it on its own, the air vehicle then becoming the air system used to deploy a series of sensors, possibly networked together.
The drone's payload, whether fixed or droppable, is not limited to imaging systems. They can include radio relays to ensure better coverage of the urban scenario (a typical snag encountered by troops), electronic warfare packages to stop mobile phone communications on the enemy side (often the most widely used system among insurgents) and, while other applications may be found, two punishing factors should never be left unconsidered--weight and power consumption--as they directly take their toll on range and endurance.
Sound of Silence ... and passing presence …
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