Unmanned Aerial Vehicles (UAV) - Scientific Technique
The British Antarctic Survey (BAS) took delivery of four Unmanned Aerial Vehicles (UAVs) late in 2006, ready for shipping to Halley on board RRS Ernest Shackleton. The two metre wing span aircraft will be flown over the Weddell Sea during the polar winter to measure the physics of sea-ice formation.
The UAV project is a collaboration between BAS, The Technical University of Braunschweig (TUB) and Mavionics, GmbH. Whilst BAS are focusing on sea-ice, Mavionics will use the wintering opportunity to test the system under harsh conditions, whilst TUB aim to study unique aspects of turbulence over an ice shelf using Halley's Instrumented Clean Air Sector.
The 4.5 kg planes each carry a light weight miniaturised turbulence probe, which measures the detailed structure of wind and temperature along the flight path. Motion sensors embedded within the probe correct for the aircraft movement; combining these records gives the heat flowing from the ice into the air. A down-looking infrared sensor measures the heat radiated into space. The difference is the rate of cooling of the ocean or sea-ice.
The UAVs are fully robotic, being programmed with GPS waypoints prior to launch. Once airborne, the computer pilot takes over, and flies the aircraft along the desired track, out of sight and out of radio range, with the data logged on board for post-flight download. Awaiting their return will no doubt be a nail-biting experience.
The aircraft are fully electric and have a range of 40 miles. To make full use of the flight they will be launched from the coast and the BAS’s Vehicle Section have modified new Tucker Terracat, a QSB 5.9 litre Cummins powered snocat to be a mobile Flying Ops. room, complete with generator, computer ports and heaters.
If all goes according to plan during 2007, additional science tasks will explore the limits of the UAV capabilities. We aim to fly them over the katabatic winds flowing off Coats Land, measure the vertical extent of surface ozone depletion, and chase atmospheric waves crossing the ice shelf. The sky’s the limit!
BAS takes delivery of four UAVs:
left to right Michael Böhm (Mavionics GmbH) John King (ACES PI), Nadine Buchmann (Braunschweig University) and Phil Anderson (ACES/FOCAS)