4-Inch Drill

The 4-Inch Drill is an electromechanical ice coring drill that takes a 104 mm (4-inch) diameter core. Cores can be retrieved from depths to approximately 400 meters. Winches with 100-, 200-, and 400-meter cables are available. The drill is of a mature design and has been used successfully for several decades. It is particularly useful on projects requiring a larger diameter core than produced by the Badger-Eclipse or Foro 400 drills. Depending on configuration, the drill can be transported by light aircraft or helicopter.

An electrothermal version of this drill, which melts an annulus around the core, can be substituted for use in ice warmer than -10° C. Both versions use core dogs to break the core off and hold it for retrieval.

IDP currently has two 4-Inch Drill systems ready for issue. A new set of core barrels was fabricated with flight geometry similar to that of the Foro drills. The barrels were tested during the 2018-2019 and 2019-2020 Antarctic field seasons. To meet continued demand for a drill of this type, IDP has designed and fabricated a drill known as the Foro 400 Drill. A 4-Inch Drill system will still be maintained; however, the Foro 400 Drill offers new capabilities and substantial weight savings. A new chips bailer was designed for use with the 4-Inch Drill system in 2019 for clearing cuttings from pilot holes drilled by ASIG Drill augers. The bailer was successfully tested in holes augered with the RAID system during the third Antarctic Field Trial (AFT-3) at Minna Bluff during the 2019-2020 field season. In late 2020, new winch crates were implemented, and the readout and control boxes were re-calibrated.