This paper introduces the method of short distance navigation, path characteristics and parameters of fighter plane, presents calculation methods of fighter plane attack envelope and missile launch envelope based on short distance navigation effciency.

The great changes have taken place in the operational environments of modem wars due to the development of military techniques and the performance improvements of weaponry equipment provide attacking aircraft many opportunities to show its predominance.

The corresponding simplified autopilot,the influencing factors and the searching algorithm of attack area are also analyzed.

Base on the models builds up model of attack area of general air to air missile ,and calculates the general attack air to iar missile ,and calculates the general attack area.

By calculating and simulating,the three dimensional attack area of the bomb has been got,and the three dimensional animation technology is applied to the software development of the real time simulation system.

Through the model,we can form the launch area of all kinds of attack conditions.

It is put forward that the optimal launch point should be selected in the common segment of attacking path and attacking area according to the rule of maximizing the overall kill probability.

Improved distinguishing attack on Py;

In this paper,the authors improve the lower bound of the linear complexity of the balanced shrinking sequences,and analyze the security of the generator with correlation attack and distinguishing attack.

A distinguishing attack on this structure is presented.