  The information of the Austrian airline flights was collected and
quantitatively analyzed by the concepts of complex network. It displays some
features of small-world networks, namely large clustering coefficient and small
average shortest-path length. The degree distributions of the networks reveal
power law behavior with exponent value of 2 $\sim$ 3 for the small degree
branch but a flat tail for the large degree branch. Similarly, the flight
weight distributions show power-law behavior for the small weight branch.
Furthermore, we found that the clustering coefficient $C$, 0.206, of this
flight network is greatly larger than that of a random network, 0.01, which has
the same numbers of the airports ($N$) and mean degree ($<k>$), and the
diameter $D$, 2.383, of the flight network is significantly smaller than the
value of the same random network, 18.67. In addition, the degree-degree
correlation analysis shows the network has disassortative behavior, i.e. the
large airports are likely to link to smaller airports. Furthermore, the
clustering coefficient analysis indicates that the large airports reveal the
hierarchical organization.
