Sensors and instruments Flashcards
Formúlan fyrir capacitance (C) er hver?
a = area of plates
d = Distance between plates
e) dielectric permittivity
C = dielectric permittivity * area of plates / distance between plates
Where is fuel pressure normally measured?
Inlet of the fuel injection metering unit
1 kg af fuel = X lbs
2.2 lbs
An aneroid capsule measures differential/absolute pressure and is used for low/high pressure measurement?
Aneroid capsule measures absolute pressure and is used for low pressure measurements.
Hver er formúla Power?
P = ?
W: Work done
T: Time
P = W / T
Hver er formúla Torque?
T = ?
mátt nota eitthvað af:
F: Force L: Lever arm R: RPM
Torque = Force * lever arm
Hvað lestu úr N1 gauge?
Engine speed
Þú getur mælt torque með því að mæla computed _____ at the fixed crown of an epicycloidal reducer of the main engine _____.
oil pressure, gearbox.
Engine torque may be expressed by:
a) Newton meter
b) Newton per meter
Newton meters
Principle of detection of a vibration monitoring system is based on the use of two ______.
accelerometers.
The engine pressure ratio (EPR) is the ratio of the ___ outlet total pressure to the compressor inlet total pressure.
turbine
Ef það kólnar og bensín minnkar í volume, hvað gerist fyrir density og hvað gerist fyrir dielectric value (Er) ?
Density eykst og dielectric value increasar líka. Muna bara að density og dielectric value virðast haldast hönd í hönd virðist vera.
vibration is indicated in the cockpit as:
a) direct reading
b) frequency
c) proportion to the speed of motor
a) direct reading
Electrical type tachometer measures the ______ of a synchronous motor energized by an alternator
rotation speed
Hvað mælir electronic torque meter system?
a) The twist in the output shaft of an engine
b) The gearbox oil pressure
a) The twist in the output shaft of an engine
The operating principle of a vibration-monitoring system can be done by using the following type of sensors: piezoelectric ___ or magnet
crystal
Hvað er eitt bar mörg PSI ?
15
Hvað mælir capacitive fuel quantity? Fuel ____
mass
Ef þú ert með electrical induction tachometer, hvað ertu laus við?
a) sensitivity to line resistance
b) dependance on aircraft power supply
c) dependance on temperature variations
a) sensitivity to line resistance
b) dependance on aircraft power supply
Ert enn dependant on temperature variations.
A float type fuel gauge is typically a ____ powered system
DC powered
The disadvantage of a single-phase AC generator tachometer is:
the importance of line _____ on the information value
resistance
Unit flow meter measures the ____ of fuel movement
quantity
Hvað táknar “4” sem þú sérð á jet engine vibration indicator?
a) 4%
b) 4 Hz
c) indication of vibration
d) 4% or 4 Hz, depends on type
c) indication of vibration
No units are specified
Pressure is defined as force per unit voume/area
area
A magnetic tachometer consists of a _____ turning inside a non magnetic drag cup
permanent magnet
1 bar = x pascals
1 bar = 100,000 pascal
Electrical induction tachometer, þarftu aircraft power supply? Er display sensitive to line resistance?
Þarft ekki aircraft power supply. Display er ekki sensitive to line resistance.
Þú þarft samt í “electronic tachometer” að vera með “power supply”. Kannski er bara trikkið að þú þarft ekki AIRCRAFT power supply. Kannski bara sitt eigið power supply.
Bourdon tube er notað í:
a) vibration detectors
b) pressure sensors
b) pressure sensors
A paddle-wheel placed in the fuel circuit of a gas turbine engine initially measures _____ by a tally of the impulses
volumetric flow
Ef þú ert með single-phase AC generator tachometer, ertu með spurious signals due to a DC generator commutator, sem ókost?
Nei. Ókosturinn er importance of line resistance on the information value.
A basic fuel flow meter incorporates a:
a) float
b) spring loaded vane
b) spring loaded vane
Q = Charge (Coulombs) C = Capitance (farads) U = Potential difference between the plates (volt)
Q = ?
Q = C * U
Charge = Capacitance * Potential difference between the plates
Ef þú ert með single-phase AC generator tachometer, ertu að fá með því suppression of spurious signals due to a DC generator commutator?
Já, þú ert líka að fá “independence of the information in relation to the airborne electrical power supply” sem ég held að þýði bara að þú ert með eigið power supply og ert ekki háður flugvélinni…… eða hvað.
Total fuel consumption is obtained by
a) integrating the fuel flow with respect to time
b) subtracting the initial fuel quantity from the remaining fuel.
a) integrating the fuel flow with respect to time
Any vibration displayed on an engine vibration monitoring system for a turbojet indicates rotor ____.
imbalance.
Mismunandi sensorar eru notaðir eftir því hvað mikill þrýstingur er á kerfi.
Hvað er notað fyrir mestann, mið og minnsta þrýstinginn:
Bellows type, Bourdon tube type, Aneroid capsule type.
Aneroid capsule type er notað fyrir minnsta þrýstinginn.
Bellows fyrir venjulegan þrýsting.
Bourdon tube type er notað fyrir mikinn þrýsting.
A three-phase electrical tachometer consists of a three-phase generator, a synchronous motor and a magnetic ____
tachometer
Held að svona three-phase electrical tachometer sé með sitt eigið small generator
Hvað er bellows sensor notaður í:
a) fuel flow indicator
b) cabin differential pressure gauge
b) cabin differential pressure gauge
Ókostur við single-phase AC generator er: the presence of spurious signals due to a DC generator commutator. Rétt eða rangt?
Rangt. Þú ert væntanlega laus við þetta með því að nota AC generator tachometer.
Er “the influence of temperature on the tachometer information” a disadvantage of a single-phase AC generator tachometer?
Nei
Það er til “stærðfræði” þrýhyrningur með
a) Coulumbs b) Volts c) Farads
Hvað er efst í þrýhyrningnum?
Coulumbs
In a 3-phase synchronous motor type tachometer indicator, the speed indicating element is a synchronous motor driving a ____ tachometer
magnetic
The electronic tachometer sensor is composed of a notched wheel rotating in front of an _____.
ATH Electronic er ekki það sama og Electric.
electro-magnet.
Is the synchroscope reducing vibrations?
Nei (ööö jú).. þetta stillir vélina svo vélar snúist á sama RPM og þá verður ekki vibrations.
Considering a modern thrust computer during a steady climb, hvað stillir tölvan af?
a) N1
b) N2
N1 is automatically adjusted as the aircraft climbs.
The probe used to measure the air intake pressure of a gas turbine engined powerplant is:
a) differential capsule
b) bellows sensor
c) aneroid capsule
d) bourdon tube
c) aneroid capsule
A vibration indicator receives a signal from different sensors (accelerometers) which indicates vibration amplitude/frequency ?
A vibration indicator indicates vibration amplitude at a given frequency.
Hvað er oftast the “master engine”?
a) outer right engine
b) outer left engine
c) inner right engine
d) inner left engine
b) outer left engine
A synchroscope shows if one engine is _____.
rotating faster
The dielectric constant of fuel is ___ that of air and varies directly/inversely with density.
Dielectric constant of fuel is twice that of air.
Varies directly with density. Því má segja: Meira density of fuel = dielectric constant verður meiri.
Ef þú ert með vatn í tönkunum þá er capacitor gauge að sýna mass of water different from zero, hvað þýðir þetta og er þetta nákvæmt?
Sýnir þetta vera að geta lesið hvað það er mikið vatn en þetta er ónákvæmt.
Hvernig sveiflast dielectric value og density saman?
meira density, meira dielectric value.
By integrating a fuel flow with respect to time we can obtain..
the volume or mass of fuel.
Hvaða græju notar þú til að mæla hydraulic pressure?
Bourdon tube
If an EPR is set at a constant value, with an increasing OAT, what happens to the thrust?
remains constant.
Lesson? Eina sem þú pælir í varðandi thrust er EPR, það er bara hitastigið sem hefur áhrif á EPR en ef EPR er fast þá náttúrulega er thrust óbreytt.
Hvernig græja er notuð til að mæla þrýsting í fuel pressure gauge?
bellows sensor
P = Power T = Torque Ohm = Angular velocity
Hvernig myndi formúlan fyrir power vera?
P = …
P = Torque (T) * angular velocity (ohm)
A synchroscope for a twin engine aircraft:
a) measures the difference in output frequencies of both alternators (one alternator in each engine)
b) measures the vibration values of both engines with a piezoelectric sensor.
a) measures the difference in output frequencies of both alternators (one alternator in each engine)
Er a single-phase electrical tachometer “a simple design” og er hann indipendant from the aircraft airborne power supply?
já við báðum.
Torque can be determined by measuring the _____ between the torque shaft and the reference shaft.
change in phase.
Ein aðferð til að mæla turbojet thrust er að mæla ___ rotation speed (N1) og hin er að mæla EPR.
compressor
Capacitance measurement is based on the variation of the dielectric of the ____.
capacitor.
The basic principle of a capacitance fuel gauge system is that the capacity of a ____ depends on the nature of the dielectric in which it is immersed.
capacitor.
The signal supplied by a transmitter fitted with a magnetic sensor, connected to an RPM indicator is an __ voltage, the frequency of which varies with the RPM, the indicator converts the signal into square ____ which are then counted
AC, pulses.
ATH ef þetta væri 3-phase AC generator dæmi, þá væri þetta ekki svona, þá væri “the indicator provided with a motor which drives a magnetic tachometer.
The capacitor type content gauges (sensors) measure the:
a) di-electric resistivity of the fuel
b) charge of condensers
b) charge of condensers
Synchroscopes give information about
a) engine speed in Hz
b) Engine speed
c) Engine speed in RPM
b) Engine speed
Hvaða græja er notuð til að mæla “fuel pressure” gauge?
Bellows sensor
The electronic tachometer measures ______ of the electric impulses created by a notched wheel rotating in a magnetic field.
frequency
The sensor feeding the EPR indicator is
a) tachometer við N2
b) temperature probe
c) pressure probe
c) tachometer við N1
c) pressure probe
A synchroscope for a twin engined aircraft measures difference in output frequencies of both _____.
alternators
The basic principle of a capacitance fuel auge system is that the capacity of a capacitor depends on the nature of the ____ in which it is immersed.
dielectric
Á þetta við um single-phase electrical tachometer? “Indication depending on the line resistance”
já
Getur N1 farið í yfir 100%?
já
Hvaða tvö atriði eru notuð til að mæla turbojet thrust?
- Compressor rotation speed (N1)
2. Engine pressure ratio (EPR)
The principle of capacity gauges is based on the capacitance variation of a capacitor with the type of _____.
dielectric
Working principle í sensorum í kerfum þar sem quantity of fuel er fundið út með capacitor type content gauges er
a) charge of condensers
b) di-electric resistivity of the fuel
a) charge of condensers
Turbulent flow around a pressure head may cause:
a. up to 95% in error due to manoeuvre induced error
b. an increase in dynamic pressure
c. up to 95% in error due to position error
d. an increase in density error
c. up to 95% in error due to position error
Static vents are usually fitted to both sides of the aircraft fuselage. This will:
a. enable a greater number of instruments to be fitted
b. reduce the position error
c. require a calibration card for each static vent
d. balance out errors caused by side slipping or yawing
d. balance out errors caused by side slipping or yawing
If the static vent becomes blocked, on an unpressurised a/c, what could you do?
a. compute altitude mathematically
b. select standby pitot source
c. open the window
d. break the VSI glass
d. break the VSI glass
Position error:
a. will depend solely on the attitude of the aircraft
b. will usually decrease as the aircraft approaches the speed of sound
c. may be reduced by the fitting of static vents
d. will usually decrease with an excess in altitude
c. may be reduced by the fitting of static vents.
Þú getur minnkað þennan error um 90%.
In high speed flight at high altitude the static source will suffer:
a. Barometric error
b. Lag Incorrect
c. Position error
d. Temperature error
c. Position error
Compressibility error:
a. causes over-reading of the ASI at all densities whenever TAS exceeds 300 kt
b. is calibrated out of the ASI at MSL ISA conditions and is only worth correcting when above MSL and CAS exceeds 300 kt
c. is calibrated out of the ASI at MSL ISA conditions and is only worth correcting when above MSL and TAS exceeds 300 kt
d. causes over-reading of the ASI at all densities whenever CAS exceeds 300 kt
is calibrated out of the ASI at MSL ISA conditions and is only worth correcting when above MSL and TAS exceeds 300 kt
A leak in the pitot total pressure line of a non-pressurised aircraft to an airspeed indicator would cause it to:
a. under-read in a climb and over-read in a descent
b. over-read in a climb and under-read in a descent
c. under-read
d. over-read
c. under-read
The speed at the lower end of the green arc on the ASI is:
a. VNE
b. VNO Incorrect
c. VMC
d. VS1
d. VS1
What does the blue line on an ASI of a twin piston engined aircraft indicate?
a. VYSE
b. VMCA
c. VNO
d. VFE
a. VYSE
Single engine best rate of climb
If the pitot tube is leaking (and the pitot drain is blocked) in a non-pressurised a/c, the ASI will:
a. over-read
b. over-read in the climb, under-read in the descent
c. under-read in the climb, over-read in the descent
d. under-read
d. under-read
Þar hefurðu það, ef hann er leaking (ekki bloced) þá einfaldlega under-readar hann sama hvað.
Excluding blockages, the full list of errors of the ASI is:
a. Instrument error, position error, barometric error, temperature error, manoeuvre induced error
b. Instrument error, position error, density error, compressibility error, manoeuvre induced error
b. Instrument error, position error, density error, compressibility error, manoeuvre induced error
VFE is the maximum speed that:
Select one:
a. the flaps may be extended in a specified configuration
b. the flaps can be operated or extended
c. the flaps may be extended in the landing configuration
d. the flaps may be extended in the take-off configuration
b. the flaps can be operated or extended
VLE and VYSE are defined as:
c. maximum speed for flight with landing gear down, best rate of climb with one engine failed
The full International Standard Atmosphere (ISA) is assumed in the calibration of:
a. The pressure altimeter only
b. The vertical speed indicator and the machmeter
c. The pressure altimeter and the airspeed indicator
d. The vertical speed indicator only
a. The pressure altimeter only
Hélt reyndar að ASI væri líka stilltur svona en greinilega ekki.
The single most significant item which makes a servo altimeter more accurate is:
a. logarithmic scale
b. electromagnetic pick-off
c. multiple pointers
d. temperature compensated spring
b. electromagnetic pick-off
The servo altimeter is superior to the sensitive altimeter because:
a. It reduces barometric error
b. It reduces high altitude error
c. It reduces temperature error
d. All of the above are correct
b. It reduces high altitude error
Nefndu þrjú atriði sem servo-assisted altimeter er að gera fyrir þig.
Increased sensitivity, more power to drive dials, more accurate at height
QNH is defined as:
a. the setting that will indicate airfield height
b. the pressure at the airfield corrected to MSL in accordance with the ISA atmosphere
c. the setting that will give zero indication on the airfield
d. the airfield barometric pressure
b. the pressure at the airfield corrected to MSL in accordance with the ISA atmosphere
On board an a/c, true altitude is shown from:
a. pressure altitude
b. density altitude
c. temperature altitude
d. standard atmosphere
a. pressure altitude
Density altitude is an altitude in the _____ at which the ISA density is equal to the ambient density in the current atmosphere
standard atmosphere
Pressure altitude may be defined as:
a. lowest forecast regional pressure
b. altitude indicated with QNH set on the altimeter
c. altitude indicated with QFE set on the altimeter
d. altitude indicated with 1013 set on the altimeter
d. altitude indicated with 1013 set on the altimeter
Absolute pressure is measured from ___ pressure (vacuum)
zero
