There are a wide variety of vehicles that are used in and
around McMurdo. These are some of the passenger carrying shuttle vehicles
that Sharon might be driving to take people to work and "around town". These
vehicles are also used to get people to and from the airfields.
For vehicles that are not going to leave base, tyres are
adequate, even if they are extra large, extra fat and extra knobbly tyres.
Around McMurdo the vehicles run on "roads" that are flat
and smooth. Away from the base, the terrain is not like this and while such
vehicles as these could get a long way off base, if they became bogged down
in soft snow or slushy ice, they would have problems in getting out again,
and that's not even mentioning what would happen if one or more wheels found
a crevasse or broke through the sea ice.
In the winter months, vehicles are hooked up to a "hitching
rail". This is a power supply rail that keeps a heater in the vehicle going
so that it is possible to start when required. Without a heater, it would
take a long time, possibly many hours to get the engine to a state where
it could start up.
Vehicles that are not required during the winter months
such as the larger passenger carriers are either garaged or raised up so
the weight is not taken on the wheels if they are left outside. Cold temperatures
mean that tyre pressures decrease if they are not pumped up. This would
cause the weight of the vehicle to flatten the tyre in conditions where
the tyre is rather brittle and so could be permanently misshapen. When the
spring arrives again, temperatures increase and the vehicles are required
again, so they are let back down to earth and put back into use.