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What are the actual benefits or advantages of using Hydraulic energy in aircraft systems, compared to pneumatic and electrical systems.


marked as duplicate by RedGrittyBrick, Pondlife, mins, SMS von der Tann, FreeMan Oct 23 '17 at 17:47

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  • $\begingroup$ It's very compact. $\endgroup$ – user3528438 Oct 23 '17 at 15:27
  • $\begingroup$ This is a broad question, I'm sure whole books could be written on this subject. $\endgroup$ – RedGrittyBrick Oct 23 '17 at 15:35
  • $\begingroup$ Just imagine using an electric motor on an excavator. It's possible, but more complex. Hydraulic is powerful, we just need a small jack to move a huge mass. $\endgroup$ – mins Oct 23 '17 at 16:21
  • $\begingroup$ Hydraulics don't compress so more positive displacement. Hydraulics run at high pressure so smaller actuators can be used. Hydraulic leaks are visible. Pneumatic leaks aren't. $\endgroup$ – Transistor Oct 23 '17 at 19:34
  • $\begingroup$ A comparison with electric motors/actuators can be seen in this thread: Why do most commercial airplanes use hydraulics instead of electric/servo motors? $\endgroup$ – Neil Patrao May 15 at 10:12