A number of readers have contacted us about the sensational information in the last issue documenting WW II planes covered with 75 metres (250 feet) of ice. Recalling the common school experiment in which a wire tensioned with weights ‘sinks’ through a block of ice, some wondered whether the planes could have sunk to that depth. However, the wire sinks through the ice in the experiment only if it is done at room temperature. Do the same experiment with the whole apparatus in a freezer, which would mimic the situation with the planes, and it does not work.1 The common explanation for the wire/ice experiment that the pressure of the wire melts the ice is wrong—such a device does not generate enough pressure to melt the ice. Heat transferred from the air in the room by the metallic wire, which is an efficient conductor of heat, melts the ice, which is a poor heat conductor, to allow the wire to ‘cut’ through.
So the planes could not have sunk through the ice; they were buried by the accumulation of snow (which becomes ice as it is compacted).