A forming system (200) includes a femtosecond laser (202) and a control unit (204) that includes one or more processors operatively connected to the femtosecond laser (202). The femtosecond laser (202) is configured to emit laser pulses onto an inner surface (218) of a face sheet of an acoustic inner barrel (120). The acoustic inner barrel (120) includes an acoustic core (128) comprising an array of hexagonal cells (130) attached to an outer surface of the face sheet that is opposite the inner surface (218) . The control unit (204) is configured to control the femtosecond laser (202) to laser drill a plurality of perforations (150) in the face sheet via emitting laser pulses at pulse durations between about 100 femtoseconds and about 10,000 femtoseconds and at frequencies over 100,000 Hz such that the perforations (150) are formed without burning portions of the face sheet or the acoustic core (128) surrounding the perforations (150).