Worksheetsinstru 51-100
Total questions: 51
Worksheet time: 26mins
Sound propagates through the air at a speed which only depends on:
temperature and the pressure.
temperature.
pressure.
density.
If the ambient temperature decreases, the TAS of an aircraft cruising at a constant Mach number will:
remain constant
increase because local speed of sound decreases
increase because local speed of sound increases
decrease because local speed of sound decreases
The Mach number is a function of the
humidity of the air.
Absolute temperature of the air.
Isobaric gradient of the fluid.
relative air temperature.
The response time of a vertical speed detector may be increased by adding:
return spring
bimetallic strip
correction based on an accelerometer sensor.
second calibrated port
The vertical speed indicator (VSI) is fed by:
dynamic pressure
static pressure
total pressure
differential pressure
The advantages provided by an air data computer to indicate the altitude are: 1. Position/pressure error correction 2. Hysteresis error correction 3. Remote data transmission capability 4. Capability of operating as a conventional altimeter in the event of a failure The combination of correct statements is:
1, 2, 3, 4
1, 3, 4
2, 3,4
1, 2, 3
In An Air Data Computer (ADC), aeroplane altitude is calculated from:
Measurement of elapsed time for a radio signal transmitted to the ground surface and back
The difference between absolute and dynamic pressure at the fuselage
Measurement of outside air temperature (OAT)
Measurement of absolute barometric pressure from a static source on the fuselage
An Air Data Computer (ADC):
Measures position error in the static system and transmits this information to ATC to provide correct altitude reporting
Is an auxiliary system that provides altitude information in the event that the static source is blocked
Converts air data measurements given by ATC from the ground in order to provide correct altitude and speed information
Transforms air data measurements into electric impulses driving servo motors in instruments
The measurement of SAT (static air temperature) by direct means is not possible on some (fast) aircraft because
the boundary layer around the aircraft gets very turbulent.
most temperature sensors have a low recovery factor.
of the effects from adiabatic compression and friction.
the airflow causes too much cooling of the sensing probe.
The ram air temperature (RAT) is defined as:
the OAT (outside air temp.) plus the SAT.
the temperature of the ram rise.
the temperature raise caused by adiabatic compression.
SAT plus the ram rise.
To obtain total air temp. (TAT) the airflow to the sensor
must not be submitted to adiabatic compression and friction.
must be laminar without any turbulence or vortex.
must be brought to rest without addition or removal of heat.
must be brought to rest with the removal of the ram rise.
Compared with a conventional gyro, a laser gyro:
is influenced by temperature
has a longer life cycle
has a fairly long starting cycle
consumes a lot of power
A laser gyro consists of:
a) a gyro with 2 degrees of freedom
b) 2 electrodes (anodes+cathodes)
c) a laser generating two light waves
d) two moving cavities provided with mirrors
In the building principle of a gyroscope, the best efficiency is obtained through the concentration of the mass:
on the periphery and with a high rotation speed.
close to the axis and with a high rotation speed.
on the periphery and with a low rotation speed.
close to the axis and with a low rotation speed.
Precession in a gyroscope is:
the tendency it has to remain in its plane of rotation
a caging device
the angular limits to which the gimbals may travel before the gyro topples and the indication becomes useless
the reaction at 90 degrees in direction of rotation caused by a applied force to the spinning wheel
Why do some gyro instruments topple when the aircraft is placed in an extreme attitude?
because the air supply to the gyro is discontinued
because the wedge-shaped erection device is displaced beyond its operating range
because the gimbals reach their limiting stops
because the air jet hits the buckets at an extreme angle
The error in a direction indicator caused by the convergence of the meridians in northerly and southerly latitudes is called:
mechanical error
drift error
transport error
turning error
Failure of the electrical supply to an electrically driven direction indicator may be indicated by:
A low ammeter reading.
A red warning flag.
Low suction.
A low voltmeter reading.
Erection systems are provided for the purpose of:
Erecting the gyro to its vertical position.
Erecting the gyro to its horizontal position.
Maintaining the gyro in its vertical position.
Erecting and maintaining the gyro in its vertical position.
The operating principle of the pendulous vane unit erecting system is:
The air flow reaction through the open vanes.
The influence of gravity on the pendulous vanes.
The influence of gravity on the gyro rotors.
The influence of gravity on the pendulous vanes and the gyro rotors.
The indications on a directional gyroscope or gyrocompass are subject to errors, due to: rotation of Earth, aeroplane motion on Earth, lateral and transversal aeroplane bank angles, north change, mechanical defects. Choose the combination with true statements only:
1, 2, 3, 5.
3, 4, 5.
1, 2, 4, 5.
2, 3, 5.
The characteristics of the directional gyro (DG) used in a gyro established compass system are:
two degrees of freedom, whose horizontal axis corresponding to the reference direction is maintained in the horizontal plane by an automatic erecting system.
two degrees of freedom, whose axis aligned with the vertical to the location is maintained in this direction by an erecting system.
one degree of freedom, whose horizontal axis is maintained in the horizontal plane by an automatic erecting system.
An airborne instrument, equipped with a gyro with 2 degrees of freedom and a horizontal spin axis is:
an artificial horizon
a directional gyro
a turn indicator
a fluxgate compass
An airborne instrument, equipped with a gyro with 2 degrees of freedom and a horizontal spin axis is:
an artificial horizon
a directional gyro
a turn indicator
a flux gate compass
A directional gyro is: 1- a gyroscope free around two axis. 2- a gyroscope free around one axis. 3- capable of self-orientation around an earth-tied direction. 4- incapable of self-orientation around an earth-tied direction. The combination which regroups all of the correct statements is:
1 - 4
2 - 4
2 - 3
1 - 3
The input signal of the amplifier of the gyromagnetic compass resetting device originates from the:
error detector.
erector system.
heading indicator.
amplifier.
A gyromagnetic compass or heading reference unit is an assembly which always consists of: 1- a directional gyro, 2- a vertical axis gyro, 3- an earth's magnetic field detector, 4- an azimuth control, 5- a synchronising control. The combination of correct statements is:
a) 2,5
b) 2,3,5
c) 1, 4
d) 1,3,5
Among the flight control instruments, the artificial horizon plays an essential part. It uses a gyroscope with : Note : in this question, the degrees of freedom of a gyro are determined by the number of gimbal rings it comprises.
one degree of freedom, whose vertical axis oriented in the direction of the real vertical to the location is maintained in this direction by an automatic erecting system
two degrees of freedom, whose horizontal axis corresponding to a reference direction is maintained in a horizontal plane by an automatic erecting system
one degree of freedom, whose horizontal axis is maintained in a horizontal plane by an automatic erecting system
two degrees of freedom, whose axis is oriented and continuously maintained to local vertical by an automatic erecting system.
When an aircraft has turned 270 degrees with a constant attitude and bank, the pilot observes the following on a classic artificial horizon:
too much nose-up and bank too high.
too much nose-up and bank too low.
attitude and bank correct.
too much nose-up and bank correct.
When an aircraft has turned 360 degrees with a constant attitude and bank, the pilot observes the following on a classic artificial horizon:
too much nose-up and bank too high
too much nose-up and bank too low
too much nose-up and bank correct
attitude and bank correct
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 correct
attitude and bank correct
too much nose-up and bank too low
too much nose-up and bank too high
A Stand-by-horizon or emergency attitude indicator:
Is automatically connected to the primary vertical gyro if the alternator fails
Contains its own separate gyro
Is fully independent of external energy resources in an emergency situation
Only works of there is a complete electrical failure
During an acceleration phase at constant attitude, the resetting principle of the artificial horizon results in the horizon bar indicating a:
constant attitude
nose-down attitude
nose-up attitude
nose-down followed by a nose-up attitude
A gravity erector system is used to correct the errors on:
an artificial horizon.
a directional gyro.
a turn indicator.
a gyromagnetic compass
You have just taken off in a fast aircraft fitted with a vacuum operated attitude indicator. While climbing straight ahead - still accelerating - the instrument may for a short while indicate:
a) a high nose-up attitude
b) a flatter attitude than actual
c) a climbing turn to the left
d) a climbing turn to the right
What angle of bank should you adopt on the attitude indicator for a standard rate (rate 1) turn while flying at an IAS of 130 Kt?
15°
18°
20°
23°
Under normal operating conditions, when an aircraft is in a banked turn, the rate-of-turn indicator is a valuable gyroscopic flight control instrument; when it is associated with an attitude indicator it indicates:
3, 4.
1, 2.
1, 3.
2, 4.
The rate-of-turn is the:
yaw rate in a turn
change-of-heading rate of the aircraft
aircraft speed in a turn
pitch rate in a turn
An airborne instrument, equipped with a gyro with 1 degree of freedom and a horizontal spin axis is a:
gyromagnetic compass
turn indicator
fluxgate compass
directional gyro
In a turn at constant rate, the turn indicator reading is:
independent to the aircraft true airspeed
proportional to the aircraft true airspeed
inversely proportional to the aircraft true airspeed
proportional to the aircraft weight
What is an operational difference between the turn coordinator and the turn and slip indicator?
the turn coordinator is always electric; the turn and slip indicator is always vacuum driven
the turn coordinator indicates bank angle only; the turn and slip indicator indicates rate of turn and co-ordination
the turn coordinator indicates roll rate, rate of turn, and co-ordination; the turn and slip indicator indicates rate of turn and co-ordination
the turn coordinator indicates angle of bank; the turn-and-slip indicator indicates turn rate in coordinated flight
While inertial platform system is operating on board an aircraft, it is necessary to use a device with the following characteristics, in order to keep the vertical line with a pendulous system:
without damping and a period of about 84 seconds
without damping and a period of about 84 minutes
with damping and a period of about 84 minutes
with damping and a period of 84 seconds
The heading reference unit of a three-axis data generator is equipped with a gyro with:
2 degrees of freedom and vertical spin axis
2 degrees of freedom and horizontal spin axis
1 degree of freedom and horizontal spin axis
1 degree of freedom and vertical spin axis
In an Inertial Navigation System (INS), the main causes of Cumulative Track errors are
wander in the levelling gyros, which causes a Schuler oscillation.
integrator errors in the second stage of integration.
initial azimuth misalignment of the platform and wander of the azimuth gyro.
because recorded value of the distance run is increasingly divergent from the true distance run.
In order to align a strapdown inertial unit, it is required to insert the local geographical coordinates. This is necessary to:
Position the computing trihedron with reference to earth.
Check operation of laser gyros.
Determine magnetic or true heading.
Re-erect laser gyros.
The sustained oscillation in the Ring Laser Gyro (RLG) is initially caused by:
the gas (or plasma) inside the triangular cavity is ionised by the voltage, causing helium atoms to collide with and transfer energy to the neon atoms.
the spontaneous return of photons to a higher energy level, which in turn produces, excited neon atoms.
the pressure fluctuation in the high pressure mixture of helium and neon gases in the triangular cavity.
the corner mirrors, which reflect the radiation energy, back to the photons.
In the northern hemisphere, during deceleration following a landing in an Easterly direction, the magnetic compass will indicate:
an apparent turn to the South.
an apparent turn to the North.
a constant heading.
a heading fluctuating about 090°.
During deceleration following a landing in Northerly direction, the magnetic compass will indicate:
no apparent turn.
an apparent turn to the East.
an apparent turn to the West.
a heading fluctuating about 360°.
The purpose of compass swinging is to determine the deviation of a magnetic
on a given heading
on any heading
at any latitude
at a given latitude
The compass heading can be derived from the magnetic heading by reference to a:
map showing the isogonic lines
map showing the isoclinic lines
deviation correction curve
compass swinging curve
The magnetic heading can be derived from the true heading by means of a:
map showing the isoclinic lines
map showing the isogonal lines
deviation correction curve
compass swinging curve
