Civil UAV-iation

Robot airships capable of operating as flying security guards, environmental sensors and communications platforms are due to undergo flight tests in the UK next month.

The unmanned airships, which will operate automatically without a remote pilot, could be used to carry out surveillance for the police, monitor air pollution, inspect power lines, track wildlife and act as low-level communication satellites, according to their UK developer, UAV specialist Remote Services.

A number of companies are investigating the potential for High Altitude Platform Station (HAPS) systems to replace expensive communications satellites, including NASA.

As well as having a wide range of applications, the airships will be cheaper to operate than manned alternatives and, unlike conventional aircraft, could stay in position for hours, said Andre Clot, director of Remote Services.

The flight tests in Dorset will check the airship’s automatic take-off and autonomous flight systems, said Clot, the industry’s representative on the government’s UAV operations working group, and its national air traffic management advisory committee.

Speaking at this month’s Unmanned Vehicles 2003 conference in Paris, Clot said the company had met considerable difficulties while attempting to tackle some of the technical issues involved in developing unmanned airships, particularly in dealing with an aerospace industry too geared towards manned aircraft.

‘The market is not ready for people like me. Looking for a transponder, a VHF box, for example, the weight is just too high. And the cost: when a Cessna transponder is just £800, why are we faced with £10,000 for a UAV?’

Clot has been researching unmanned airships since 1999, and in 2001 Remote Services completed an EU-funded exploratory study into the technology. The company’s prototype airship is a helium-filled 10m oval balloon, slightly larger than a Cessna aircraft. It uses ducted fans – propellers partially enclosed in a nacelle. These are powered by lithium ion batteries and solar panels. The panels are also used to recharge the batteries.

Using these power sources the ship can stay up for five hours, but Clot believes future, larger, airships could operate overnight.

To gain Civil Aviation Authority approval for the airships to operate in UK airspace, the company still has more development work to undertake on the avionics and sensor systems needed to ensure safe flying, and to allow the ships to monitor the ground and sea below. Development work on the avionics systems will include a radar with a 25km range, which is necessary for collision avoidance.

The airship technologies are being developed by a European consortium, the Airscan programme, with 1.5 million Euros (£1million) of funding from the EU and 110,000 Euros (£77,000) from the European Space Agency. This covers the commercial and technological challenges that will be faced by future operators of civil UAV systems, and is supported by four partner firms, including Remote Services, and three contractors from the Netherlands, Sweden and the UK.