A pair of lightweight, robotic planes have made the first unmanned flights over Antarctica’s icy expanses.

Driven by propeller, the machines made 20 low-altitude sorties, including four over the Weddell Sea. The unmanned aerial vehicles (UAVs) were launched by catapult but flew autonomously until landing. During some of the test flights the machines were fitted with miniaturised instruments to collect data for use in predictive climate models.

One of the biggest uncertainties in those models is the physics of sea-ice - how it freezes and how it melts,” said Dr Phil Anderson of the British Antarctic Survey (BAS), one of the team that carried out the tests. A lot of this happens during the Antarctic winter - the nine-month period when we can’t get ships and aircraft to the bases - so we decided to see if we could [collect this data] by robot aircraft.”

Flying the UAVs in the extreme conditions of the Antarctic is not without problems. As well as the difficulty of handling the machines in thick gloves and mitts, the cold played havoc with the sensitive electronic equipment and even the elastic bungee cord used to loft the craft into the air.

“We found that it set solid at -10C; so we had to build a very long, snaky duvet cover to go over the bungee just to keep it warm enough, long enough, to do the launch,” he explained.

However, Dr Anderson believes the craft will play a big part in future exploration of the continent, surveying hard to reach and dangerous places. This capability has been exploited for a long time by the military which uses UAVs for surveillance and communication.As such, research efforts are ongoing around the world to boost the endurance, range and capabilities of craft.

Last year, UK defence firm Qinetiq smashed the official world record for the longest-duration unmanned flight when its vehicle flew for 54 hours during tests. The Zephyr plane could be used for military applications, as well as for Earth-observation and communications, according to the company. Earlier this year, the US National Oceanic and Atmospheric Administration (Noaa) announced a $3m (£1.5m) investment into the technology. It will use UAVs to track hurricanes and Pacific storms, as well as monitor summer ice-melt in the Arctic.

“Their time has come,” said Dr Anderson.

Another interesting development has been announced by Flight Global who are also experimenting with UAV’s.

Officials from Flight Global have said that DARPA will probably sign a contract to create an UAV that is able to stay in the air for about 5 years at a time. The spokesmen from DARPA characterise their project, entitled “Vulture,” as a “persistent pseudo-satellite capability in an aircraft package.” Generally speaking the aircraft is able to fly over a single area, communicating or performing analysis for years at a time.

Having such grand goals the company has to overcome some serious barriers. One of the major obstacles is linked with the fact that designers have to figure out the way to supply power to such an aircraft during the long missions. One solution would be to panel the outer edge with solar panels. At the moment this is not a feasible idea as there are no high quality solar cells developed which are upto the challenge of such a large scale project. In addition it is worth mentioning that the aircraft will carry a 1000 pound (450 kg) payload in terrible winds at an altitude of 60,000 to 90,000 feet. In regard to the design of the aircraft, it will probably be the one seen in the picture, developed by NASA, however, there is no certain time table on when the craft will actually be ready.

Besides problems with providing power to the craft, engineers are working on maximizing aero-structural efficiency and avoiding the deterioration of materials during their long-time exposure to stratospheric flight.

Basically the aircraft operates like a satellite, which is, however, not regulated by orbital mechanics. “It could be positioned over the battle, at 65,000ft versus 260 miles,” outlined DARPA’s Wade Pulliam. According to Pulliam, the Vulture is a pseudo-satellite, the operation of which in the stratosphere and not in the low Earth orbit would give a 65 dB upgrading in communications capability and considerably increase on-board sensor resolution.