CAP 4 Haydraulic System

Question 1

Primary flight controls?

Answer 1

Roll spoilers,rudder,aileron and elevator

Question 2

1bar in psi?

Answer 2

1bar= 14.8psi

Question 3

Pascal’s law

Answer 3

Pressure transmitted equally in all direction throughput the fluid.
Fluid is incompressible ,but air it is

Question 4

how to change fluid on systems?

Answer 4

Oil of correct specification and from an unopen container

Question 5

Transmission of power

Force x displacement

Answer 5

Input force x input stroke = output force x output stroke

Question 6

Pressure?

Answer 6

Force/area

Question 7

Active hydraulic sys?

Answer 7

Active hydraulic system is the circulation of fluid system.

Driven by hydraulic pump

Question 8

Passive system ?

Answer 8

Driven by human

Question 9

Active system can supply?

Answer 9

Constant pressure&raquo_space; closed centred sys

Pressure only when demanding» opened centred sys

Question 10

Typical hydraulic operating pressure values?

Answer 10

High pressure sys»3000/4000 psi (for easa exams.)

Low pressue sys» 2000psi

Question 11

Hydraulic fluid properties?

Answer 11

>low viscosity
>resistance to foaming (emulsifying)
>lubricator and corrosion resistence
>resistance to heat ( thermally conductive)
>chemically stable (Neutral reaction with maerils)
>Low freezing point (-70c)
>high boiling point (80c)
>non flammable (flash point above 100C)
>good storage properties

Question 12

Two types of hyd fluids?

Answer 12

Mineral base E.G. DTD 585» colour red,suitable for high press sys, synthetic rubber seals and hoses only

Synthetic Skydrol»colour purple ,fire resistant does not support combustion,used in sys with butyl rubber /teflon seals.

Question 13

From where Hydraulic leakages can come from?

Answer 13

From hydraulic systems

Or from IDG

Question 14

ADVANTAGES OF HYD SYS

Answer 14

> GOOD WAY TO PROVIDE LARGE AMOUNT OF POWER
VERY LITTLE ENERGY LOSE IN TRANSMISSION OF POWER
LEAKS ARE RELATIVELY EASY TO SPOT
LIGHTER THAN EQUIVALENT MECHANICAL SYS
PROVIDE POWER ADVANTAGES

Question 15

HYDRAULIC SYS DISADVANTAGES?

Answer 15

> fluid highly corrosive
the force being generated require strong structures
large sys will still be quite heavy
susceptible to fluid contamination and damage line
health risk and environmental hazard

Question 16

Elements of hyd sys?

Answer 16

>reservoir
>accumulator
>Double acting cylinder
> non return valve
>pump 
 >Selector valve

Question 17

What EDP stands for?

Answer 17

Engine driven pump

Question 18

TWO WAYS TO POWER THE HYD SYSTEMS?

Answer 18

EDP (ENGINE DRIVEN PUMP)

ELECTRICALLY DRIVEN PUMPS