The “Phoenix” aims to take autonomous variable buoyancy powered craft to higher altitudes to operate like satellites in low orbit.
The UK’s Manufacturing Technology Centre (MTC) based in Coventry has undertaken a significant role in an innovative project to develop the world’s first unmanned variable buoyancy-powered ultra-long endurance aircraft.
Now, the autonomously-controlled Phoenix aircraft has undergone successful test flights and has shown that it has the potential to take the lead in the world development of pseudo-satellites.
Pseudo-satellites are able to fly, remotely-controlled or autonomously, at very high altitudes for long periods of time, in some cases often during months of flight. They can fly above commercial aircraft routes and above turbulence and moisture. In this way, they complement conventional satellites and can be used for earth-mapping, scientific observation and intelligence gathering.
The Phoenix aircraft has been developed by a consortium of industrial partners, universities and members of the High Value Manufacturing Catapult. The Catapult centres that were involved were the MTC’s advanced production systems group, the National Composites Centre and the Centre for Process Innovation. University partners included the University of Bristol, Newcastle University and the University of the Highlands and Islands. Industrial partners were Banks Sails, Stirling Dynamics, IQE and TCS Micropumps.
MTC engineers made extensive use of National Instruments’ hardware and software suites to build, program and test the aircraft’s control system including hardware-in-the-loop (HIL) tests of its autonomous pilot system developed by Stirling Dynamics. The MTC has also provided testing facilities and expertise for hardware components including pumps and actuators provided by TCS Mircropumps. In addition support was provided to the flight trials including assembly, piloting and testing.
The use of such “catapult” centres enabled expertise and facilities to be gathered to provide the development, simulation and testing capabilities required for a project of such technical complexity. Without such collaboration between catapults, industry and academia, the length of time required to achieve such goals as those in the Phoenix project would be significantly extended.
MTC technology director Ken Young said the Innovate UK-funded Phoenix project was an exciting collaborative venture at the cutting edge of aerospace technology.
An interesting element of the aircraft is its propulsion. The 15 metre long Phoenix spends half its time as a heavier than air aeroplane and the other as a lighter than air helium balloon. The repeated transition between these two states provides its sole source of propulsion.
This capability comes partially from a transfer of marine engineering into the field of aeronautics and, according to Young, the variable-buoyancy propulsion technology has been used before for remote controlled underwater vehicles but has never been used for the propulsion of a large aircraft. The power for moving the flight-control surfaces, the valves and pumps comes from a battery charged by an array of lightweight flexible solar cells.
“The technology involved in this project is truly cutting-edge and has the potential to take the UK into the lead when it comes to this kind of innovation,” says Young.
Founded by three universities in the Midlands area and a commercial partner, the MTC now has an industrial membership base that includes some of the UK’s major global manufacturers.
According to Young, the Phoenix project is a good example of how the MTC is able to provide a competitive environment to bridge the gap between university-based research and the development of innovative manufacturing methods.