Abstract:
Commercial air freight operations have grown in importance in
recent years, due mainly to cost reductions caused by increasing aircraft
and freight-terminal efficiencies. The bulk of this traffic is carried
in the underfloor holds of wide-body passenger aircraft, but there is
a significant sector of the market served by 'dedicated' freighters
such as the 747F and DC8-63F. These aircraft are often equipped with
standard containers and pallets which are loaded at factories or freight
depots. The largest and most efficient container is the 8 ft x 8 ft x 20 ft
size
NASA felt the need to study the air-freight market and commissioned
the extensive C.L.A.S.S. study (Ref.1). This report suggested that
significant operating cost savings would be required, together with
improved ground interfaces, to make more inroads into the surface transport
market.
It studied the economics of aircraft derived from current types,
together with new designs. The former was more immediately attractive,
but a market existed for new aircraft from the mid 1990's.
The most attractive new type would be a long range aircraft with
payload in the 75 to 165 ton range. The lower size aircraft was
slightly more economic, but would pose grave airport frequency
saturation problems and therefore a larger aircraft was preferable. Aircraft
much above the 165 ton class however, would lead to development
costs higher than the market could stand.
An aircraft of about 165 tons payload seemed to be a good solution
which could be made more attractive if it were designed to satisfy both
civil and military requirements, thus spreading development costs. This
philosophy was aimed at during the design of the Lockheed C-141 but
too much emphasis was placed on military properties and no civil versions
were sold. This should be avoided on a new design which should be capable
of augmenting and partially replacing current fleets of 747F, DC10 CF
and Lockheed C-5A aircraft … [cont.].
