Free access to EASA ECQB 2022!


The hydraulic device which functionality is comparable to an electronic diode is a ? Information > helipad

exemple question 142
A diode a one way electricity gate actually a diode means a device that has two electrodes but word has come to mean a one way electricity valve the most common function of a diode to allow an electric current to pass in one direction to block it in opposite direction thus diode can be thought of as an electronic version of a check valve.


Hydraulic fluid entering the hydraulic pump is slightly pressurised to ?

exemple question 143
Hydraulic fluid entering hydraulic pump slightly pressurised to Prevent cavitation in pump. Cavitation occurs when a liquid moves within tubing or pipes at very fast speeds causing absolute pressure of liquid to drop drastically this process occurs with little loss of heat if absolute pressure drops below vapour pressure of liquid cavitation will form this phenomenon more serious in viscous liquids than in thin liquids cavitation causes separation of gases that are within liquid (such as air or water vapour) from liquid itself bubbles would form then collapse in case of a liquid entering suction side of a pump pressure would be low for liquid to move from one place to another it would have to expend energy thus causing a further decrease in pressure if you pressurize hydraulic fluid entering in hydraulic pump you will avoid cavitation in pump.


In the hydraulic press schematically shown what balancing Force would be acting on the right hand side The diagram is not to scale 824 ?

exemple question 144
In hydraulic press schematically shown what balancing force would be acting on right hand side the diagram not to scale 824 Prevent cavitation in pump. Cavitation occurs when a liquid moves within tubing or pipes at very fast speeds causing absolute pressure of liquid to drop drastically this process occurs with little loss of heat if absolute pressure drops below vapour pressure of liquid cavitation will form this phenomenon more serious in viscous liquids than in thin liquids cavitation causes separation of gases that are within liquid (such as air or water vapour) from liquid itself bubbles would form then collapse in case of a liquid entering suction side of a pump pressure would be low for liquid to move from one place to another it would have to expend energy thus causing a further decrease in pressure if you pressurize hydraulic fluid entering in hydraulic pump you will avoid cavitation in pump.


exemple question 145
Assuming an accumulator pre charged with air to 1000 psi and hydraulic system pressurised to 1500 psi accumulator gauge will read Prevent cavitation in pump. Part of an accumulator's job to store energy in form of hydraulic fluid under pressure that can be used short time if main system fails or needs help at peak times pressure gauges installed in hydraulic pneumatic systems are used to indicate existing hydraulic pneumatic pressures the accumulator gauge will read 1500 psi if main system fails it will read 1000 psi.


exemple question 146
Internal leakage in a hydraulic system will cause An increased fluid temperature. As there internal leakage hyd pump will cycle on off (depending on pump type) to maintain system pressure increasing friction with pump fluid thus increasing fluid temp.


exemple question 147
On large aeroplanes equipped with power brakes main source of power derived from The aeroplane's hydraulic system. As there internal leakage hyd pump will cycle on off (depending on pump type) to maintain system pressure increasing friction with pump fluid thus increasing fluid temp.


exemple question 148
When powering up a hydraulic system level in reservoir will The aeroplane's hydraulic system. The air occupies space that would otherwise be occupied hydraulic fluid thus when hydraulic system becomes pressurized some fluids flows into different pipes.


8
An accumulator in a hydraulic system will Store fluid under pressure. The air occupies space that would otherwise be occupied hydraulic fluid thus when hydraulic system becomes pressurized some fluids flows into different pipes.


9
In typical hydraulic system represented in graphic assuming hydraulic pressure throughout and no internal leakage 825 A condition of hydraulic lock exists no movement of piston will take place. a condition of hydraulic lock exists no movement of piston will take place.


10
A hydraulic shuttle valve Enables an alternate supply to operate an actuator. the shuttle valve sometimes fluid must come from more than one source to meet demands of a complex system at other times an emergency system might be needed to provide pressure if normal system fails (the emergency system will usually only actuate essential components) the shuttle valve can isolate normal system from an alternate or emergency one a typical shuttle valve contains three ports normal system inlet alternate system inlet an outlet inside shuttle valve there a sliding part predictably called shuttle whose purpose to seal off an inlet port which itself will contain a shuttle seat when a shuttle valve in its normal position fluid can flow freely from normal system inlet port to actuating unit the shuttle seated against alternate system inlet port held there normal system pressure where it remains until alternate system activated fluid under pressure then directed from alternate system to shuttle valve forcing shuttle to seal off normal inlet port fluid from alternate system then has a free flow to outlet port.


11
To protect against excessive system pressure a hydraulic system usually incorporates A high pressure relief valve. The pressure relief valve there to dump fluid back to reservoir when pressure in system gets too high as it will do when system not being used the engine driven pump working all time .


12
The ram air turbine rat provides emergency hydraulic power Flight controls in event of loss of engine driven hydraulic power. a ram air turbine (rat) a small turbine that connected to a hydraulic pump or electrical generator installed in an aircraft used as a power source the rat generates power from airstream due to speed of aircraft.


13
A hydraulic low pressure alert the first indication of The pump output pressure being insufficient. The pressure transmitter located at pump output.


14
For an aeroplane hydraulic supply circuit correct statement The accumulators constitute a reserve of hydraulic fluid maintained under pressure a pneumatic back pressure (air or nitrogen). The pressure transmitter located at pump output.


15
The reservoirs of a hydraulic system can be pressurized By bleed air from engine. The pressure transmitter located at pump output.


16
A pressure regulator used in a hydraulic system In conjunction with a constant delivery type pump. A constant delivery pump forces a fixed or unvarying quantity of fluid through outlet port during each revolution of pump the pressure regulator unloads or relieves power driven pump when desired pressure in system reached thus it often referred to as an unloading valve when a constant delivery type pump being operated pressure in line between pump selector valve builds up to a desired point a valve in pressure regulator automatically opens fluid bypassed back to reservoir.


17
Filters in hydraulic systems often incorporate pop out indicators to Warn of an impending by pass situation. Filters are necessary in hydraulic systems filtering out contamination debris a filter may include a filter bypass provision a filter bypass allows fluid to flow around (bypass) filter when pressure across filter high (i e filter clogged) a bypass functions similar to a priority valve where pressure overcomes a spring when pressure sufficiently high.


18
Maximum power output and low mass of aeroplane hydraulic systems can be achieved with High system pressure low volume flow. Filters are necessary in hydraulic systems filtering out contamination debris a filter may include a filter bypass provision a filter bypass allows fluid to flow around (bypass) filter when pressure across filter high (i e filter clogged) a bypass functions similar to a priority valve where pressure overcomes a spring when pressure sufficiently high.


19
Parameters to monitor a hydraulic system in cockpit can be Pressure fluid temperature quantity. Filters are necessary in hydraulic systems filtering out contamination debris a filter may include a filter bypass provision a filter bypass allows fluid to flow around (bypass) filter when pressure across filter high (i e filter clogged) a bypass functions similar to a priority valve where pressure overcomes a spring when pressure sufficiently high.


20
The purpose of an accumulator in a hydraulic system To damp fluid pressure variations. Filters are necessary in hydraulic systems filtering out contamination debris a filter may include a filter bypass provision a filter bypass allows fluid to flow around (bypass) filter when pressure across filter high (i e filter clogged) a bypass functions similar to a priority valve where pressure overcomes a spring when pressure sufficiently high.



Exclusive rights: Content under private and protected license, reproduction prohibited and prosecuted.

719 Free Training Exam