||SR 80-3, cores, drilling, drills, geophysical prospecting, glaciology, greenland, ice, ice caps
||The "Danish Deep Drill" was developed at the University of Copenhagen. The drill, which will be used to obtain ice cores from the Greenland Ice Sheet, was tested at the U.S. Army Cold Regions Research and Engineering Laboratory. The drill is battery-operated and has a down-hole microprocessor-based control section and delicately balanced chip removal system. It is a lightweight, electro-mechanical drill designed to obtain a 10.2-cm-diameter core in 2-m lengths. There are potential problems in chip recovery and storage, malfunctions of the computer of batteries, leaks in the pressure chamber, spin-out or rotation of the drill, and the very close tolerances required by the drill design. Tests are recommended that will help eliminate some of these potential problems and determine the drill's overall strengths and weaknesses. The drill is a very complex and delicate instruments that will require constant maintenance, modification and monitoring when in use.