To a formulation of the flutter problem for a conical shell with a small apex angle / I. A. Kiiko, M. A. Nadzhafov. // Vestnik Moskovskogo Universiteta. Seriya 1. Matematika. Mekhanika. 2009. ? 4. P. 49-53 [Moscow Univ. Mech. Bulletin. Vol. 64, N 4, 2009. P. 89-92].

The well-known piston theory formula for the excessive aerodynamic pressure is used in the majority of works devoted to the panel flutter of shells. In this paper a refined expression for the excessive pressure is proposed to take into account the irregularity of undisturbed flow parameters. The case of moderate supersonic velocities is studied in detail. The critical velocity problem is reduced to a new eigenproblem in the panel flutter theory.

Key words: conical shell, internal flow, irregularity of flow, flutter.