BASIC HYDRAULIC SYSTEMS AND COMPONENTS
Subcourse Number AL 0926
US Army Aviation Logistics School
Fort Eustis, Virginia 23604-5439
4 Credit Hours
Edition Date: September 1994
This subcourse is designed to provide instruction on the concept and operation of the basic components
of the hydraulic system. It also describes the various components of a typical hydraulic system, their
construction and functions, and their relationship to each other.
When the term hydraulics is applied to aircraft, it means a method of transmitting power from one
location to another through the use of a confined fluid. The functions performed by hydraulic systems in
aircraft include assisting in flight control, extending and retracting landing gear, positioning flaps,
operating hoists, raising and lowering cargo doors, and starting engines.
The hydraulic systems used in Army aircraft are dependable and relatively trouble-free. The
maintenance requirements are small in comparison to the work the system performs.
This subcourse is to be completed on a self-study basis. You will grade your lessons as you complete
them using the lesson answer keys which are enclosed. If you have answered any question incorrectly,
study the question reference shown on the answer key and evaluate all possible solutions.
There are no prerequisites for this subcourse.
This subcourse reflects the doctrine which was current at the time it was prepared. In your own work
situation, always refer to the latest official publications.
Unless otherwise stated, the masculine gender of singular pronouns is used to refer to both men and
TERMINAL LEARNING OBJECTIVE
You will demonstrate a knowledge of the basic components of the hydraulic system,
including the devices which actuate, discharge, and control the flow of hydrauli