A combined hydraulic and pneumatic actuation system including a cylinder, a first piston, and a second piston. The cylinder may include a first cylinder portion configured to hold or retain a first fluid and a second cylinder portion configured to hold or retain a second fluid. The first piston can be operatively coupled or in fluid communication with the first fluid, and the second piston can be operatively coupled or in fluid communication with the second fluid. The second piston may be disposed between the first cylinder portion and the second cylinder portion. In an embodiment, the first piston can move or translate axially within the cylinder independently of the second piston, and an increase in pressure in the second cylinder portion can actuate the first piston and the second piston. Further, in embodiments, the first fluid can comprise a liquid, and the second fluid can comprise a gas.