way to leave a clean operating surface for aircraft.
At the Pegasus site, construction activities dur-
The 45 cm of snow is left as a wearing surface
ing the experimental phase generated large berms
and to provide a soft surface for the aircraft tires
along both sides of the runway. Each time the
to pass along, as mentioned earlier.
runway snow cover is removed, snow is added to
Other mechanical means could perhaps be used
these berms. We are currently studying means of
to remove the protective snow cover. However,
removing the snow berms using natural means.
we doubt that any could be more efficient than
During the 19941995 austral summer season, we
the gradersnowblower combination. Natural
will establish test plots to try out several schemes
methods, such as taking advantage of strong
of slightly accelerating snow loss in a controlled
winds of a favorable direction, may not occur at
manner using the wind, warm air temperature,
the right time and are probably unreliable at most
peak solar radiation, and combinations of these
sites.
as driving forces (Lang and Blaisdell 1997).
Using the snowblower, we add the stripped
snow to the natural snow along the sides of the
runway. This will have the effect of placing the
MONITORING AND
runway in a depression, which is not generally
DATA ACQUISITION
desirable since the potential for snow drifting on
the runway is greatly increased. Consequently,
All measurements made during the process of
following opening of the runway (stripoff and
siting, construction, and maintenance of a glacial
beginning flights), these flanking snow berms will
ice runway should be entered into some form of
require attention. The most important detail is to
computer database. Long-term operation, main-
shape the berms so that they minimize the poten-
tenance, and reliability of the facility will rely
tial for slowing the wind stream enough to allow
heavily on knowledge of the site and its unique
airborne snow to drop out. This is accomplished
characteristics. It is unwise to rely solely on
by ensuring a smooth surface on the berms (i.e.,
individual's personal experience and knowledge
no scarps) and keeping the slopes of both sides
to manage the runway. An ideal database would
of both snow berms at or below 14%. Using the
be PC-based and would be divided into several
means discussed in the section on snow manage-
sections. It should have the capacity for entering
ment, these berms should ultimately be reduced
general information (such as observations of en-
or removed entirely. Ideally, except for the run-
vironmental patterns and operational techniques),
way surface itself, the site should be brought back
input of infrequent measurements, and output
to the surface topography present before any con-
from automated data gathering systems (such as
struction began. This will probably require main-
AWS information or thermocouple readings). Soft-
tenance crews to work on reducing a given year's
ware should be available for user-driven printing
snow berms during the following season's cold
and plotting of synoptic data and for displaying
period, when snow strength is great enough to
short-term and long-term trends. Any informa-
support heavy equipment. Snow berms along the
tion that could be of use in making decisions
flanks of the runway can become a serious prob-
about the maintenance and operation of the facil-
lem, since each year another layer of protective
ity should be conveniently stored in the database
snow cover will be removed from the runway
and regularly updated and accessed by facility
and placed along the sides.
managers.
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