A starter air valve comprising: a housing comprising an inlet at a first end , an outlet at a second end opposite the first end , and a center portion between the first end and the second end , the outlet being fluidly connected to the inlet through a fluid passage ; a first piston located within the housing between the first end and the center portion , the first piston comprising: a first cupped portion configured to form a first chamber with the housing proximate the first end ; and a second piston located within the housing between the second end and the center portion , the second piston comprising: a third cupped portion configured to form a third chamber with the housing proximate the second end ; wherein the first piston is configured to regulate airflow through the fluid passage by adjusting at least one of a first pressure within the first chamber and a second pressure within a second chamber ; wherein the second piston is configured to regulate airflow through the fluid passage by adjusting at least one of a third pressure within the third chamber and a fourth pressure within a fourth chamber , and characterized by said first piston comprising a second cupped portion opposite the first cupped portion , the second cupped portion being configured to form the second chamber with the housing proximate the center portion and said second piston comprising a fourth cupped portion opposite the third cupped portion , the fourth cupped portion being configured to form the fourth chamber with the housing proximate the center portion . a housing comprising an inlet at a first end , an outlet at a second end opposite the first end , and a center portion between the first end and the second end , the outlet being fluidly connected to the inlet through a fluid passage ; a first piston located within the housing between the first end and the center portion , the first piston comprising: a first cupped portion configured to form a first chamber with the housing proximate the first end ; and a second piston located within the housing between the second end and the center portion , the second piston comprising: a third cupped portion configured to form a third chamber with the housing proximate the second end ; a first cupped portion configured to form a first chamber with the housing proximate the first end ; and a second piston located within the housing between the second end and the center portion , the second piston comprising: a third cupped portion configured to form a third chamber with the housing proximate the second end ; wherein the first piston is configured to regulate airflow through the fluid passage by adjusting at least one of a first pressure within the first chamber and a second pressure within a second chamber ; wherein the second piston is configured to regulate airflow through the fluid passage by adjusting at least one of a third pressure within the third chamber and a fourth pressure within a fourth chamber , and characterized by said first piston comprising a second cupped portion opposite the first cupped portion , the second cupped portion being configured to form the second chamber with the housing proximate the center portion and said second piston comprising a fourth cupped portion opposite the third cupped portion , the fourth cupped portion being configured to form the fourth chamber with the housing proximate the center portion . <EOS>