This SAE Aerospace Recommended Practice (ARP) is intended as a guide in defining the requirements for aerospace piston separated hydraulic accumulators, including details pertinent to the design, fabrication, and performance of the accumulator. This type of accumulator has a piston separator and contains both high-pressure gas and fluid. The accumulator is used in aerospace hydraulic systems of the following types as defined in SAE AS 5440 with design operating pressures of up to 8000 psi (55,160 kPa).Type I: -65 to +160 mDF (-54 to +71 mDC) fluid temperatureType II: -65 to +275 mDF (-54 to +135 mDC) fluid temperatureFor commercial aerospace or helicopter applications, the information and guidelines of SAE ARP 4752 or SAE ARP 4925 respectively, are considered.