29 Hydrolic Power Flashcards
what is the purpose of a hydraulic system
make accomplishing mechanical tasks easier (require less force)
draw a diagram of a basic hydraulic system. Include the following labels: actuator, reservoir, pump, valve, accumulator, high pressure relief valve, suction line, return line, high pressure line
see picture.
what are the main components of the hydraulic system of the aircraft
accumulator, resevoir, pump, high pressure relief valve, actuator, valve
what are the three lines in the hydraulic system
high pressure line, suction line, return line
what is a typical pressure of the high pressure components of the hydraulic system
200 bar or 3000 psi
what makes a good hydraulic fluid
- trend is lower density
- good performance at low temps
- nonflamable (mostly)
- non reactive with metal (to no damage metal)
what is typically used in aircraft as the hydraulic fluid
phosphate ester-based fluid (synthetic)
what is included in the ATA 29 system?
components used in creating hydraulic power. includes pumps, lines, .. not the systems which they power
how does a servo valve operate
there are three stages with different connections between the highpressre + return line and the two hydraulic chambers of the actuator. The default stage is no connection between either. The second two are high pressure to either the right of left hydraulic chamber of the actuator. The valve can slide “slowly” between stages to allow for proportional control.
what is a key feature of the servo valve (as opposed to a selector valve) that allows it to be used for flight controls. (as opposed to langing gear)
it valve moves gradually in between positions for proportional control
what are typical uses of a selector valve and servo valve
selector -> landing gear
servo-> flight controls
