Abstract: A ground testing installation for an aircraft jet engine having a nozzle that is steerable relative to the longitudinal axis of said engine, the installation comprising:a silencer having a body that is generally in the form of an elongate cylinder and intended to be disposed behind the nozzle of said engine; anda funneling device for funneling the jet of exhaust gases from the engine, which device is disposed between the engine and the silencer, said device comprising a generally cylindrical outer shell which flares in the vicinity of its end for facing the engine under test, and a generally cylindrical inner shell which is concentric with said outer shell and is intended to deflect the jet of exhaust gases when said jet or the nozzle of the engine under test is at some angle of inclination relative to the longitudinal axis of said engine.

Abstract: An electrical apparatus and method for electrically simulating noise resulting from the thermodynamic expansion of a gas inside a chamber whose volume is varied, is characterized in that it comprises, in series, a capacitor of fixed capacitance and means for varying with respect to time the potential at at least one of the terminals of the capacitor, the potential variation depending on the variation of the volume with respect to time and on the nature of said expansion.