Sound absorbing panels

A noise reducing system comprising an acoustic panel attached to a surface that defines a passenger compartment of a transportation vehicle, the acoustic panel comprising:

• a backing layer;
• a honeycomb core attached to the backing layer with a first adhesive layer, the honeycomb core comprising a first side, a second side, a thickness that extends from the first side to the second side, and a plurality of walls that define a plurality of honeycomb cells, wherein the plurality of honeycomb cells extend through the thickness of the honeycomb core from the first side to the second side;
• a mesh layer comprising a second impregnated adhesive layer attached to the honeycomb core;
• and
• an acoustic fabric face sheet attached to the mesh layer with a third adhesive layer comprising an acrylic, a polyester, a urethane, a rubberized adhesive, or a combination thereof, wherein the acoustic panel is configured so that the acoustic fabric face sheet is visible to passengers during use of the transportation vehicle, and the third adhesive layer is arranged such that it overlies only the plurality of walls of the honeycomb core and is not directly on the plurality of walls of the honeycomb core.

A method for forming an acoustic panel, comprising:

• attaching a backing layer to a first side of a honeycomb core with a first adhesive layer, wherein the honeycomb core further comprises a second side opposite to the first side, a thickness that extends from the first side to the second side, and a plurality of walls that define a plurality of honeycomb cells, wherein the plurality of honeycomb cells extend through the thickness of the honeycomb core from the first side to the second side;
• attaching a first side of a mesh layer comprising an impregnated second adhesive layer to the second side of the honeycomb core;
• and
• attaching an acoustic fabric face sheet to a second side of the mesh layer with a third adhesive layer comprising an acrylic, a polyester, a urethane, a rubberized adhesive, or a combination thereof, wherein the acoustic panel is configured so that the acoustic fabric face sheet is visually exposed during use of the acoustic panel, and the third adhesive layer is arranged such that it overlies only the plurality of walls of the honeycomb core and is not directly on the plurality of walls of the honeycomb core.