Unmanned aerial systems are commonplace for many air forces around the world, but the technology can often be expensive and bespoke systems can take years to build. Now aerospace manufacturers are looking at ways they can bring down the costs of these aircraft by equipping tried-and-tested legacy systems like the F-16 and Black Hawk with optionally manned capabilities.
"Sikorsky selected the optionally manned route rather than full autonomy to support its aims of improving safety across its entire military and civilian product range."
A medevac helicopter lands near the site of an attack of an armoured patrol and its crew members carry injured personnel on board before taking off for the nearest trauma centre. In flight, the condition of an injured combatant deteriorates and all hands are needed - including the medically-trained pilot. The pilot flicks a switch and the helicopter automatically takes over navigation to its designation and lands safely on arrival, avoiding hazards en route.
This is the vision for a new generation of unmanned and optionally manned aircraft evolved from current and legacy manned systems that could not only save cash-strapped militaries money and time but also offer new mission capabilities. Three new programmes are demonstrating just how far this exciting new technological development could take military aircraft.
Sikorsky Manned/Unmanned Resupply Aerial Lifter (MURAL) programme
In March, Sikorsky carried out the first demonstration of optionally piloted flight using a Black Hawk helicopter. Then, in May, the company announced it had developed the first product to feature Matrix Technology -- hardware and software that replace traditional mechanical control systems -- by converting a retired UH-60A Black Hawk helicopter into an optionally piloted variant capable of a wide spectrum of missions.
"The aim of the programme is to show we can insert autonomous technology into the Black Hawk platform to enhance its mission flexibility, improve its safety of operation and enable it to operate with greatly reduced pilot workload," says Chris van Buiten, vice president of Sikorsky Innovations.
"It's not just making an autonomous platform; it's making it more capable and functional when it's carrying people as people. That creates a whole new set of requirements and raises the bar in terms of the integrity of the autonomy system."
Sikorsky selected the optionally manned route rather than full autonomy to support its aims of improving safety across its entire military and civilian product range, incorporating technology from manned platforms, starting with fly-by-wire then adding high-level augmentation and pilot assistance.
"You can call it autonomy except that the operator is sitting inside the aircraft," explains Igor Cherepinsky, Sikorsky's chief engineer for autonomy. "We will eventually see piloting this vehicle becoming very mission-oriented, where pilots become mission managers, and their actual location is mission-dependent. There are plenty of missions where you still want human eyes there at the event, but you don't necessarily want the human being to be doing all the control of the aircraft. Our optionally piloted vehicle allows them to be there, in the cockpit of the aircraft, or in the back of the aircraft."
To achieve this, the converted UH-60A will first operate using a fly-by-wire kit before demonstrating full unmanned capabilities with perception-system-in-the-loop using a variety of sensors installed on board. These, integrated with normal airfield data, will enable the helicopter to perform a fully autonomous mission where it can take off, fly avoiding obstacles, find its own landing zone and land.
While Sikorsky is also developing a purely unmanned full-size platform through its X2 programme with Boeing, using existing platforms to develop an optionally manned system the size of a Black Hawk from scratch would be a billion-dollar plus.
"This isn't a little quad-rotor that you make in your basement in a month; these are very large sophisticated systems," says van Buiten. "We're leveraging the existing design, its global support network, and, in the case of both those aircraft, millions of hours of safety record and improvement really create a great foundation."
Crew safety is equally important, and Sikorsky wants its technology to reduce the incidence of 'controlled flight into terrain', the leading cause of fatalities in military and civilian rotorcraft.
"A good helicopter with a flight crew that is confused, disorientated, overloaded, experiencing very high workload can result in the loss of the aircraft," says van Buiten. "We see this technology that makes the aircraft safer and easier to fly as giving the aircraft 'virtual bumpers' to avoid controlled flight into terrain."
However, the new technology is likely to drip-feed into new models of aircraft rather than being delivered as a fully-fledged final product.
"It's not just a big bang of all of a sudden you get the entire kit to convert the Black Hawk into a fully-autonomous platform," says van Buiten. "There's functionality that can be added along the way to improve the existing platform and its handling qualities before inserting fly-by-wire technologies that will enable new levels of autonomy. We've seen an example of that in the commercial world; we offer automated offshore oil rig approach software that has been very popular with the commercial customer, which falls short of full autonomy, but takes one of the highest workload tasks and automating it."
Sikorsky is working with a number of specialist partners on the MURAL programme. Think-A-Move has contributed the speech recognition engine, Kutta Technologies supplies the portable back-pack ground station, and the company is in discussions with Advanced Optical Systems to use its sensors to identify loads on the ground.
The company sees the demonstration as a step towards a future where all Sikorsky military and civilian products will be offered as optionally piloted models where the operator skill set required fundamentally changes from a traditional pilot to a mission manager.
"In the MURAL demonstration, we saw the first glimpse of a minimally-trained operator," says van Buiten. "We took a young flight-test engineer who did not know how to fly a Black Hawk and gave him the Kutta ground control system and let him mission-manage a Black Hawk in flight. It was really the first glimpse of what this future is going to look like."