A double layer structural honeycomb sandwich noise suppression panel for use in severe environments such as aircraft turbine engine housings. Two honeycomb core sheets having multiple cells transverse to the sheets are sandwiched around and bonded to a septum sheet consisting of a wire cloth sheet alone or bonded to a sheet of perforated material. A thin sheet of impervious material is bonded to one surface of the sandwich and a facing of thin perforated sheet material is bonded to the other sandwich surface. The panel has improved simplicity, structural strength with unusually light weight.