SAE AS595

Description / Abstract: This SAE Aerospace Standard (AS) establishes the general requirements for the design, construction, acceptance and qualification testing of flat cut-off pressure compensated, variable delivery hydraulic pumps, used in civil aircraft hydraulic systems. It also provides parameters for a Procurement Specification to be used in conjunction with this AS for each pump.

NOTE: Hydraulic pumps may incorporate features such as a clutch in the input drive, which will not be covered by this standard.

Field of Application

This AS is primarily for hydraulic pumps driven by an engine; however, it also can be applied to pumps driven by other power sources such as electric motors, ram air turbines and engine bleed air turbines. These pumps may be soft cut-off pressure compensated, variable delivery type due to input power limitations.

Pumps conforming to this standard are intended mainly for use in commercial aircraft hydraulic systems conforming to the general requirements of ARP4752, and to the regulations of 14 CFR Part 25 and/or CS-25/JAR 25. However, pumps conforming to this AS can also be used in:

• Civil aircraft hydraulic systems conforming to the regulations of 14 CFR Part 23 and/or CS-23/JAR 23. For these applications, the equivalent 14 CFR Part 23/CS-23/JAR 23 requirements should be used in place of the 14 CFR Part 25/CS-25/JAR 25 requirements.

• Helicopter hydraulic systems conforming to the regulations of 14 CFR Part 27 and/or CS-27/JAR 27. For these applications, the equivalent 14 CFR Part 27/CS-27/JAR 27 requirements should be used in place of the 14 CFR Part 25/CS-25/JAR 25 requirements.

• Helicopter hydraulic systems conforming to the general requirements of ARP4925, and to the regulations of 14 CFR Part 29 and/or CS-29/JAR 29. For these applications, the equivalent 14 CFR Part 29/CS-29/JAR 29 requirements should be used in place of the 14 CFR Part 25/CS-25/JAR 25 requirements.