  Our objective is to study the observability and unique continuation property
of the adjoint of a linearized compressible fluid structure interaction model
in a 2D channel. Concerning the structure we will consider a damped
Euler-Bernoulli beam located on a portion of the boundary. In the present
article we establish an observability inequality for the adjoint of the
linearized fluid structure interaction problem under consideration which in
principle is equivalent with the null controllability of the linearized system.
As a corollary of the derived observability inequality we also obtain a unique
continuation property for the adjoint problem.
