A gas turbine jet noise reduction apparatus including a variable geometry gas turbine engine nozzle comprising a circumferentially distributed array of nozzle flap panels supported for alternate collective splaying and gathering motion, with the collective splaying motion of the flap panels being from a narrow position defining a minimum cross-sectional area at a nozzle exit plane, to a wide position defining a maximum cross-sectional area at the nozzle exit plane. A plurality of nozzle seal panels is supported in a circumferentially distributed array within the array of nozzle flap panels. A seal panel actuator is operatively engageable with the seal panels to deflect the seal panels radially inward into respective deployed positions to reduce jet noise by increasing exhaust stream mixing with ambient air.