Sensors and Instruments Flashcards
The EPR is computed by:
dividing turbine discharge pressure by compressor inlet pressure.
The position error of the static vent on which the altimeter is connected varies substantially with the:
Mach number of the aircraft
The density altitude is :
the altitude of the standard atmosphere on which the density is equal to the actual density of the atmosphere
When an aircraft has turned 90 degrees with a constant attitude and bank, the pilot observes the following on a classic artificial horizon :
too much nose-up and bank too low
A gravity type erector is used in a vertical gyro device to correct errors on:
an artificial horizon
The QNH is by definition the value of the:
altimeter setting so that the altimeter, on the apron of the aerodrome for which it is given, reads the elevation.
In a standard atmosphere and at the sea level, the equivalent airspeed (EAS) is:
equal to the true airspeed (TAS).
A thermocouple type thermometer consists of:
two metal conductors of different type connected at two points.
One of the disadvantages of an electronic tachometer is the:
necessity of a power supply.
The principle of capacity gauges is based on the capacitance variation of:
a capacitor with the type of dielectric.
A synchroscope is used on aircraft to:
set several engines to the same speed.
Modern low altitude radio altimeters emit waves in the following frequency band:
SHF (Super High Frequency).
The operating frequency range of a low altitude radio altimeter is:
4200 MHz to 4400 MHz.
The “Bourdon tube” is used to measure:
pressure.
Given: M is the Mach number Ts is the static temperature Tt is the total temperature
Ts = Tt /(1+0.2. M²)
A pilot wishes to turn left on to a southerly heading with 20° bank at a latitude of 20° North. Using a direct reading compass, in order to achieve this he must stop the turn on an approximate heading of:
160°
If a manifold pressure gauge consistently registers atmospheric pressure, the cause is probably;
leak in pressure gauge line.
The operation of the radio altimeter of a modern aircraft is based on:
frequency modulation of the carrier wave.
In an engine vibration monitoring system for a turbojet any vibration produced by the engine is:
amplified and filtered before being fed to the cockpit indicator.
In order to measure temperature the cylinder head temperature (CHT) gauge utilises a:
thermocouple consisting of two dissimilar metals.
According to the range of pressure to be measured (low, medium, high), different types of pressure sensors are used.
Classify the following sensors by order of increasing pressure for which they are suitable:
1- bellows type
2- Bourdon tube type
3- aneroid capsule:
3,1,2
The signal supplied by a transmitter fitted with a 3-phase AC generator, connected to RPM indicator, is:
a three-phase voltage, the frequency of which varies with the RPM; the indicator is provided with a motor which drives a magnetic tachometer
The signal supplied by a transmitter fitted with a magnetic sensor, connected to an RPM indicator is:
an AC voltage, the frequency of which varies with the RPM; the indicator converts the signal into square pulses which are then counted
A vibration indicator receives a signal from different sensors (accelerometers). It indicates the:
vibration amplitude at a given frequency
