US Patent 11130564 Strut shrink using accumulator as energy source

Systems and methods for enabling aircraft shock strut shrink are provided. The system may comprise a shock strut comprising a shrink piston, an accumulator comprising a gas piston and a hydraulic chamber, wherein the gas piston is configured to apply gas pressure to the hydraulic chamber, and a first valve in fluid communication with the accumulator. The system may further comprise a second valve, wherein the second valve is in fluid communication with a vent, the pneumatic cylinder, and the gas piston, wherein the first valve is in fluid communication with the hydraulic chamber and the shrink piston.