What is the differences between Aircraft Hydraulic and Pneumatic systems?
Hydraulic systems utilize fluid to transmit force. Examples are brake systems, landing gear struts and (in more complex aircraft) flight control or landing gear actuator systems. Pneumatic systems utilize gas (usually air) to transmit force. Examples are gyroscopic instrument air systems and (in more complex aircraft) deice boot inflation systems. Since gasses are compressible, and fluids are not, hydraulic systems have a greater speed of response and transmit higher forces. Pneumatic systems are generally supplied by atmospheric air (pumped), or engine bleed air from the compressor sections of turbine engines. Hydraulic systems are supplied by on-board reservoirs and/or accumulators. Pumps are used to amplify control forces input by the pilot when higher forces are required to move an actuator. Pneumatic systems are generally lighter than hydraulic systems, due to the absence of fluid. If you are a student pilot or mechanic, please take time to go back and study these topics in your c
