The UAV revolution

Today, much smaller UAVs have emerged with miniaturised navigation, propulsion, control and surveillance systems. Some have amazing endurances. The Scan Eagle boasts more than 24 hours’ endurance and can operate to 24,500ft at speeds between 48 and 80kt. The Warrigal, meanwhile, operates at spends between 24 and 40kt depending on conditions and mission type.

One of the emerging issues, of course, is how UAVs and manned aircraft sharing the same skies are managed, with both demanding the same control and separation standards. Scan Eagles, undertaking pilot operator training, mix regularly with all manner of aviation operations at Watts Bridge near Amberley.

Miniaturised GPS and inertial navigation systems – like those on a 747 or A380 – are the navigation hearts of small ‘smart’ UAVs. The Warrigal uses the world’s smallest autopilot weighing in at a meagre 16.7gr, while allowing fully automatic flight and scanning unless the ground-based pilot intervenes through a patented ‘click-N-fly’ system.

A UAV’s detection systems offer precise measurement and reconnaissance using their day/night optical systems and can fly any pattern by commanded by an operator and at a fraction of the cost.

The 20kg Scan Eagle can be launched from land or ship and is retrieved by skyhook or in a malfunction can be descended at very low speed. The V-TOL Warrigal, weighing in at just 1.1kg uses improvised strips or a deep stall.

Exemplifying the potential value of small UAVs in the Australian environment, a NSW report into helicopter-based shark detection trials showed an average detection rate of around just 15 per cent.

Although this number is woefully low to any reader, it is exacerbated by the superior performance a small UAV could offer for which an appreciation of search planning methodology is useful. Track data – which is determined by the area of interest – and intelligence govern a search area. Secondly, the detectability of the target against the background surface determines the optimum height for detection, track spacing and speed used, with the aim of 100 per cent coverage. This in turn should create as close as possible to a 100 per cent probability of detection (POD), an outcome that also governs the number of aircraft and observers necessary to fulfil the mission.

Compared to the 15 per cent success rate of helicopter operations, both the Scan Eagle and Warrigal offer 100 per cent coverage and POD – at minimal cost flying closer-spaced runs as low and slow as the mission demands.

Both UAVs can be easily reconfigured for night searching and flown in visibility conditions aircraft and helicopters can’t. Importantly, both not only offer a higher probability of detection, but would do so at negligible risk to the public, something highlighted in 1950 when a shark patrol Wirraway crashed at Maroochydore killing and injuring 13 people.

Optimum UAV operations would favour mobile Scan Eagles being flown by dedicated UAV operators, while the smaller Warrigal would be flown by trained emergency response people in the area of immediate interest. In the recent floods, fires and some searches, Scan Eagles could have quickly covered vast areas while Warrigals could have immediately responded in their own localised areas.

Both Insitu Pacific and V-TOL Aerospace provide professional training to operators at UAV ‘pilot’ schools.

As the demand for emergency services helicopters has grown – just as has the variety and complexity of missions – the size of rotary-wing aircraft has grown from Jet Rangers to now Bell 412s. These larger helicopters are now becoming the accepted norm as medical and rescue and recovery equipment increases in scale.

Tasking a Bell 412 on some distant search that a Scan Eagle or Warrigal could do at a fraction of the cost and arguably more efficiently has the effect of robbing a community of its critical emergency vehicle.

Furthermore, UAVs are not without their own rescue devices. Whereas once before a 35-man inflatable raft and buoyant supply containers linked by 400m of floating rope – all in weighing around 200kg – and dropped with the accuracy of an eyeball from 200ft, the Warrigal, for example, can drop two 80g inflatable rafts each capable of supporting 120kg person for 24 hours.

“Tasking an AW139 on some distant search that a UAV could do at a fraction of the cost has the effect of robbing a community of its critical emergency vehicle”

If emergency services and their government and private sector sponsors want cost-efficiency and immediate response, small UAVs represent a clear benefit. They also preserve helicopters for their primary airlift functions that a UAV simply cannot perform.