Abstract: Microwave communication and radar systems that employ a blazed microwave reflection grating are disclosed in which the grating comprises an array of electrical conducting scattering elements having plane parallel surfaces that face in the same direction. The plane parallel faces are positioned in parallel equally-spaced planes to provide a generally stair-step, or Venetian-blind type structure. Microwave energy beamed onto the plane parallel surfaces of the array exits at a diffraction-mode angle within the reradiation pattern of the individual scattering elements of the array. Frequency steering of the exit beam in one plane of the array is provided by varying the frequency of the illuminating beam.

Abstract: In an automatic flight control system of the type having automatic stabilizer trim control, the long term, constant altitude cruise trim threshold limits which alter the maximum and minimum pull-in/drop-out deflection of the elevator relative to the stabilizer minimize the steady-state downward deflection of the elevator, thereby reducing unnecessary aerodynamic drag and realizing significant savings in fuel costs.