Abstract: The invention concerns a sandwich designed for making multilayer structures resistant to impact and thermal aggressions of the type including a core 2 interposed between an external skin 1 and an internal skin 3.The external skin panel 1 consists of an assembly of at least three layers made integral by sealing or bonding: a first layer 4 made of composite material, a second layer 5 made of a synthetic cellular material with a low thermal conductivity coefficient, a third layer 6 obtained by lamination of a composite material. The second layer 5 consists of a honeycomb and the composite material of the first layer 4 and third layer 6 consists of glass fiber reinforced epoxy resin. A nonwoven polyester layer 7 is interposed between layers 4 and 5. The sandwich panel includes a metal sheet 8 adhering by cofusion to layer 5 via a thermal plastic film 9, said sheet being made of aluminum or aluminum alloy, steel or titanium which can be in the form of a film with a thickness below 1 mm.