404 POLAR PROBLEMS 



minutes be covered with rough pack-ice that would either crush the 

 machine or hold it fast for an indefinite period. Landing on the Arctic 

 tundra during summer would be extremely dangerous owing to the 

 swampy condition of the surface and to the growth of large clumps of 

 tufted grass, known in Alaska as "niggerheads." Accumulated 

 driftwood and other obstructions would make forced landings on the 

 Arctic beaches hazardous but would not be so dangerous as landing 

 on the tundra. High, offshore winds are a source of danger to water 

 craft in the Antarctic, and the steep ice-cliff coast lines of the Antarctic 

 Continent afford few sheltered harbors in the event of an onshore 

 drift. 



If the purpose of the expedition is to take limited ground observa- 

 tions at many points in the Arctic, the airship offers advantages. 

 Under normal conditions personnel can be landed from an airship 

 for an hour or so and picked up again when their observations have 

 been made, the airship hovering in sight during that time. Because of 

 the greater numbers carried in airships the results of observations can 

 be worked out quickly and in greater comfort, and further observations 

 can be taken in the vicinity if necessary. From the writer's experience 

 in making three airplane landings far from shore on the Arctic pack 

 ice and from observations taken during 2000 miles of flying over the 

 Arctic Sea there seems to be a possibility of finding many safe landing 

 fields on the Arctic pack ice, both for airplanes and for men from an 

 airship. 



Although perhaps 90 per cent of the pack-ice surface is too rough 

 for safe landings and a forced landing there might lead to disaster, 

 there are many stretches of level ice on which a plane might be landed 

 with safety. The essential knowledge to make landing on the Arctic 

 pack-ice a safe procedure can be gained only by actual experience in 

 travel on foot over a variety of ice surfaces and long experience in 

 observing from an airplane. Various colorings and shades indicate 

 various thicknesses of ice, but the colorings and shades differ under 

 different conditions of light, and only long personal experience on the 

 ice and in the air in the Polar Regions will give an aviator the necessary 

 qualifications for sound judgment in this respect. 



Other necessary qualifications for safe landings on the ice are 

 experience of pack-ice movement and the ability to interpret meteor- 

 ological conditions skillfully. The navigator or pilot should be able to 

 determine whether it is safe to remain on an ice floe for even an hour or 

 whether there is danger from ice fracture or pressure. 



Wireless Communication Between Base and Plane 



With modern wireless apparatus it is now possible to maintain 

 communication between an airplane in flight and its base of supplies. 



