A pneumatic actuator air flow control system includes a pneumatic rotary actuator (PRA) and a solenoid air flow control valve (SAFCV). The PRA contains an air reservoir and a vane housing allowing pressurized air to rotate an air-driven vane. The SAFCV includes a flow control valve body (FCVB), a pilot solenoid valve (PSV) and a switch system, wherein the FCVB and the PRA can be connected to direct the pressurized air into the air reservoir, and the PSV is used to control the pressurized air in and out of the PRA to change the vane's rotation movement in the vane housing. Additionally, the switch system allows users to switch between a double-acting and fail-safe operation. When there is no pressurized air and/or electrical power and if an emergent need to open or close the valve, a manual override in the PSV can be used without further installation of a declutchable manual gear operator or external piping when there is no pressurized air and/or electrical power.