logical data can identify a predominant wind di-
available (vehicle types) and the nature in which
rection for the majority of normal conditions and
the runway will be used. For instance, if the gla-
for storms or high wind circumstances. Since the
cial ice runway will be used for daily operations,
sites considered for a glacial ice runway will most
the establishment and runway should be situated
likely not be in areas where suitable weather
close to each other and the connector route will
records are kept, a weather station will need to be
need to be durable and fairly easily traveled.
installed, or indirect evidence of winds will need
There will need to be a large area adjacent to
to be used. It is mandatory that at least a year of
the glacial ice runway that can support parked
wind speed and wind direction data be collected
aircraft for loading, unloading, fueling, and main-
for any site of interest, in particular during the
tenance. These ramp areas should be viewed as
time of year most likely for aircraft operations.
expendable, since contaminants such as exhaust
These data will assist greatly in choosing runway
soot, fuel and lubricant leaks, and melt due to
alignment.
aircraft and vehicle engines will degraded the ice
Obstructions are another major factor for con-
surface. They must be situated within easy access
sideration in alignment of runways. Mountains
of the runway, but they may, in time, become
are the most obvious type of obstacle encoun-
degraded to the point where they will need to be
tered. Minimum climb out and glide slope re-
abandoned. Ideally, there should be several loca-
quirements for the design aircraft will dictate the
tions where a ramp area could be situated, so that
zone of acceptable air traffic and thus the runway
when one is discarded another can be employed
headings. Besides the usual precautions concern-
without losing the runway facility.
ing obstacles as accounted for with minimum glide
The nature of the aircraft payload may also
slopes and climb-out gradients, the site specific
influence siting of the glacial ice runway. If only
katabatic winds (gravitational/thermal winds)
passengers, personal luggage, and small scien-
that often occur in regions of exposed glacial ice
tific instruments are to be delivered to the site,
should be considered.
essentially no cargo handling equipment will be
At the Pegasus site the prevailing wind is from
required at the runway and transportation to the
the east at approximately 1.12.4 m/s (2.55.5
main camp will be straightforward. However, if
mph) and the strong (storm) wind from the south
building modules or other heavy and/or bulky
at approximately 1123 m/s (2550 mph) (Keller
cargo will regularly be ferried to or from the air-
et al. 1995). In the development of the Pegasus
port, the ramp areas must be able to support air-
runway, there were not resources available to con-
craft unloading equipment (e.g., loaders, Fig. 20)
struct two runways of 3050 m to accommodate
and there must be suitable areas for staging and
both wind directions. With this constraint, and
stockpiling cargo.
noting that the glaciological conditions at the site
favored a north-south trending runway, we
Access for construction
elected to align the runway with the strong wind
Site selection may also be influenced greatly
direction.
by the ability to get runway construction equip-
To the south, the selected runway alignment
ment and facilities to the site. Most potential sites
aims toward the gap between Black and White
are likely to be remote and the logistics of the
Islands (Fig. 19). The runway headings are desig-
initial deliveries will need to be considered care-
nated 34 and 16 (true headings). The first rise
fully. Overland traverse will be the most eco-
above the ice shelf to the south is 26 km distant
nomical in most cases, but it may not be feasible
and is about 250 m high along the vector of the
due to crevasse fields, soft snow conditions, large
runway. To the north, there is only level ice and/
distances, or prohibitive terrain between the site
or water for a significant distance.
and the nearest trailhead. It may be possible to
airlift with heavy-lift helicopters the necessary
equipment, but this may seriously limit the size
Logistical suitability
Any site considered for an airfield must allow
of equipment used or require major disassembly
reasonable accessibility to the camp or establish-
of some pieces.
ment that the runway supports. Suitable surface
Another potential option is to first establish a
traffic routes to and from the runway should be
skiway on snow fields near the glacial ice runway
identified, and their length and the terrain en-
site. The skiway may require some grooming or
countered must be carefully considered. These
could be situated where minimal roughness and
issues will need to be compared with the assets
long-wavelength bumps exist. This runway would
19
Previous Page
