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Mission Planning A 900-nautical-mile trackline loop was laid out, based on scientific need, ocean currents and the best available information of ice loca- tion from late July 2011 to the recovery date in mid-September. Local current information was obtained from the U.S. Naval Oceanographic Office's Navy Coastal Ocean Model data. Ice conditions were monitored from the National Ice Center and the National Snow and Ice Data Center. Other researchers were contacted for coordination and possible vessels for recovering the AWGs, if needed. Flybys of UpTempO ocean thermistor buoys, which were The Arctic Wave Glider in the Beaufort Sea. developed by scientists at the University of Washington's Applied Physics Laboratory, were carried out in the oper- ating area, and the National Center for Atmospheric Re- search's HIAPER (High-performance Instrumented Airborne Platform for Environmental Research) Pole-to-Pole Observa- tion Flights took Arctic Basin carbon-dioxide measurements from the HIAPER aircraft. Staging was done out of Prudhoe Bay, Alaska, with BP plc (London, England) offering temporary access to storage facilities and to the west dock, where the Liquid Robotics deployment team loaded the RV Ukpik. Beaufort Sea Deployment The AWGs were deployed in July 2011 from the RV Uk- pik 20 nautical miles north-northeast of Prudhoe Bay, Alas- ka, and were held in a box pattern for 24 hours for observa- tion prior to being sent to the first waypoint. During the mission, both vehicles followed the same route, separated by 12 hours to observe diurnal signals. Tem- perature data were collected at one-minute intervals, tagged for time and position, stored on board and transmitted every five minutes for the 54-day mission. Waypoints were adjust- ed according to ice location, and in one instance, the AWGs were turned south to avoid getting too close to the forecast location of the ice pack. Adverse currents were encountered several times, mainly in the northwest sector of the operating area, but active pilot- ing by Liquid Robotics kept the vehicles within a few miles of track and separated by 12 hours. Twenty images were cap- tured and transmitted, including one from August that had ice in the background. Upon recovery in September 2011, some minor ice-damage to the hulls was evident, but did not affect the performance of the vehicle. Mileage for AWG-1 was 1,325 nautical miles and for AWG-2 was 1,418 nautical miles, exceeding the goal of 900 www.sea-technology.com SEPTEMBER 2012 / st 29