Fluid attenuator systems and methods for attenuating fluid ripple waves within a main fluid line (e.g., a main hydraulic fluid line of an aircraft hydraulic system). At least one attenuator branch conduit may be provided in fluid communication with and at substantially a right angle to the main fluid line with a porous material positioned therewithin (e.g., at an open inlet or a closed distal end of the at least one attenuator branch conduit). The porous material may be a metallic or ceramic open-cell foam material. Multiple attenuator branch conduits may be provided with each having a different length as compared to the others. In such embodiments, the porous material may (or may not) be positioned within the different length attenuator branch conduits (e.g., at an open inlet or a closed distal end of respective ones of attenuator branch conduits).