Abstract: The intensity and spectral content of a jet aircraft and/or missile plume is simulated with a xenon lamp that derives an optical beam which propagates through a filter. The filter prevents optical energy in the visible light region from propagating through it, to prevent eye damage, and enables an output beam to be derived that simulates the intensity and spectral content of the plume. The lamp is normally maintained in a keep-alive status, and its beam power is increased to simulate sudden changes of plume intensity. The beam is selectively passed and blocked by a shutter downstream of the filter to simulate plume presence and absence. The distance between the simulated plume and a target is simulated by controlling the opening of an iris in the beam path. The lamp, filter and drive mechanism for the shutter are cooled by air drawn into a housing by a fan and by fins inside of the housing. The fins are in dull black, radiation absorbing, optical energy trapping structures.