The tripod jack is used in routine maintenance procedures that requires raising the nose, wing or tail section to allow maintenance personnel to work on those parts of the aircraft. Multiple tripod jacks placed in the correct locations under an aircraft will allow the entire aircraft to be lifted off of the ground. Some jacks are able to be used on many different aircraft provided the correct aircraft jack pads are used. Jack pads allow jacks to make contact with the aircraft without damaging the surface.
Most aircraft jacks, especially those used with larger aircraft, are hydraulic, however, mechanical jacks are still in use on some lighter aircraft. One main advantage of using the hydraulic jack is that a small piston pump is able to generate the large pressures required to move the jack ram and aircraft upwards with minimal effort on the part of the operator. Although they both have similar mechanical structures, the hydraulic principle which the hydraulic jack uses makes it a more complex system and as such needs additional maintenance to maintain its operation.
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