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Palmer Station, Antarctica, which is located on Anvers Island west of the Antarctic Peninsula, has been supported entirely by ice breakers and cargo ships during the austral summer; a capability for air support would extend this season, improve the movement of essential cargo and personnel, and provide for emergency support. This technical note presents the feasibility of establishing a skiway for ski-equipped C-130 aircraft on the Marr Ice Piedmont about three miles from the station. It also describes the reconnaissance techniques used in February 1969 to locate the skiway site and safe access route through the marginal crevasse zone between this site and Palmer Station for one-ton capacity tracked carriers.

The annual sea ice on McMurdo Sound, Antarctica, is extensively used as a runway by heavy cargo aircraft. Safe utilization requires a better understanding of thickness, temperature, and strength - basic properties affecting the load-carrying capacity of ice sheets. Thickness and temperature are the two parameters required to use load-carrying curves being developed by the Naval Civil Engineering Laboratory (NCEL). Annual sea-ice thickness varies seasonally between 8 and 11 feet by the end of the growth period. Thinning by bottom melting starts about mid-December and continues until breakout in late January or early February. The average ice-sheet temperature has increased each season since Deep Freeze 65 (DF-65), and becomes essentially isothermal about the same time bottom melting begins. For operational safety, the ice sheet should be monitored for thickness and temperature as described in this report. The surface temperature, T sub s, measured at a depth below the influence of diurnal air temperature fluctuations, is needed to select the correct NCEL load-carrying curve. A depth of 24 inches is beyond the influence of this fluctuation and is suitable for determining T sub s on a daily or weekly basis. The average ice-sheet temperature, based on the freezing point of seawater, is (T sub s + 1.8)/2. Both the surface temperature and the average ice-sheet temperature gradually change with time. (Author)

A two part study was conducted to determine the snowdrift characteristics of the new South Pole Station and properties of snow foundations at the South Pole. Snowdrift characteristics were studied using 1:150 scale models in a wind cut and 1:10 scale models in the field. From the scale model tests, areas of high and low snow accumulation rates were determined for a static undisturbed state in the vicinity of the station. The physical properties of natural and compacted snow were determined for the South Pole and three load settlement tests were conducted on different foundation materials. The load settlement tests showed that the settlement rate of footings on natural snow is several times greater than footings on compacted snow. (Author)

The Naval Civil Engineering Laboratory (NCEL) investigated problems concerning subsurface temperatures, snow accumulation, and potential frost heaving beneath buildings at McMurdo Station, Antarctica. Two buildings were selected for a comparative study of their effects upon earth-fill foundation and underlying permafrost. One building has an open below space beneath it for air circulation and the other is completely enclosed. (Author)

The sea ice adjacent to McMurdo Station, Antarctica, has been used extensively since 1956 for aircraft operations, travel, freight hauling, and loading and unloading ships. A study of some factors affecting the safety and efficiency of these operations was made during the summer of 1964-65. The factors included cracks, seal holes, pressure ridges, and breakout of the ice in this area at the end of the 1964-65 summer season. It was found that cracks which did not penetrate the ice sheet, and seal holes in thick ice did not seriously affect the bearing capacity of the ice; however, flooding in pressure zones and around seal holes on the ice sheet created a hazard to travel where the ice was covered with snow. In addition, it was observed that breakout of the ice south of McMurdo Station began about 3 weeks after the ice exhibited minimum strength, maximum temperature, and a rapid decrease in thickness, and 4 to 6 weeks after maximum daily air temperatures were observed at McMurdo Station. It was concluded that additional research is needed to provide adequate knowledge on the influence of those factors affecting the safe and efficient utilization of sea ice in Antarctica.