CHAPTER 5. MAINTENANCE
A site chosen at a natural blue-ice field at high
ment maintenance, this person will be respon-
latitude may require essentially no maintenance
sible for making sure that all vehicles are clean
short of cleaning up any contaminants that drop
and free from any fluid leaks.
onto the ice. Snow management will likely be the
The maintenance crew and supervisor should
most important maintenance issue associated with
have unrestricted access to persons familiar with
the majority of glacial ice runways. We see this to
snow and ice science and to the body of literature
include both protection of the runway from melt
on this subject. Consultation with specialists will
problems and protection against snow accumula-
greatly assist in dealing with these issues in a
tion and inundation. The goal of runway mainte-
timely manner so that action can be taken as soon
nance should be to preserve the natural balance
as possible. This can often significantly reduce
of conditions at the site. If properly sited, the
the amount of work necessary to respond to un-
runway will be able to reside at this location in
expected conditions and may mean the difference
usable form with an absolute minimum of pertur-
between maintaining and losing the runway in a
bation from what would happen at the site if it
given season. It will certainly extend the life of
was uninhabited. To do otherwise is unnecessary
the runway.
and inefficient. In polar regions, huge amounts of
energy are required to maintain an area the size
SNOW MANAGEMENT
of an airport at a state other than natural.
Obstacles, even small surface features, can trap
snow and initiate accumulation. Depending on
PERSONNEL
the need at the time, runway maintenance per-
The number of persons required to maintain a
sonnel will either want to encourage or limit this
glacial ice runway will vary considerably accord-
behavior. At the Pegasus site, we identified sev-
ing to the site and its environmental characteris-
eral means of encouraging snow accumulation
tics. Further, variations may exist from year to
when it was in our interest to cover an area of
year, and at times throughout the year. These
exposed ice on the runway surface. The most con-
latter variations in required workforce size can-
trollable method was to generate small windrows,
not be anticipated with any degree of accuracy,
spaced a meter or so apart, perpendicular to the
and a flexible workforce might be best suited for
direction of the prevailing wind. Depending on
the site. However, this will only work if the col-
the amount of loose snow available in the area
lateral duties of the flexible members of the
and wind speed (which governs the amount of
workforce are not also dictated by adverse
snow carried by the wind), these windrows will
weather. We discovered that it was almost al-
trap on their lee side an amount of snow at least
ways the case that when the Pegasus runway
equal to the volume of the windrow. Windrows
required a large effort, as did many other facili-
can be produced by using a grader, or more effi-
ties in the McMurdo area, and that personnel
ciently, a windrow drag such as we fabricated
who might normally be available to assist us were
(Fig. 68).
frequently occupied with other important tasks.
Once the windrows were "full" we found that
A site supervisor will be essential. In the case
it was necessary to level the area (using snow
of a polar camp with multiple airfields (e.g.,
planes or drags; Fig. 69, 70, and 71) and to com-
McMurdo), it may make sense to have one indi-
pact the snow using a pneumatic-tire roller (Fig.
vidual supervise all runways so that decisions
72). By compacting the snow onto the ice or exist-
can be made with a attitude toward what is most
ing snow surface, it became bonded to the surface
beneficial for the entire polar program.
and dense enough to resist wind erosion. We
For the Pegasus facility, we recommend two
found that, even using heavy rollers (3550 tons
full-time maintenance personnel with intimate
or 3245 tonnes, with greater than 690-kPa or 100-
knowledge of the site. There should also be access
psi tire pressure), compacting was important as
to one or two other operators who can be avail-
soon as the snow reached a depth that resulted in
able when storms and drifting snow occur. The
a compacted layer of no more than 10 cm. Com-
maintenance staff should also include a half-time
pacting more snow than this results in a strong
mechanic/fabricator. In addition to usual equip-
density distribution in the compacted layer which
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