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Gyroscope

Preguntas

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  • 1) 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 :
  • the angular velocity of the aircraft about the yaw axis
  • the bank of the aircraft
  • the direction of the aircraft turn
  • the angular velocity of the aircraft about the real vertical
  • The combination of correct statements is:
  • A) 3, 4
  • B) 1, 2
  • C) 2, 4
  • D) 1, 3

  • 2) Inside an artificial horizon:
  • A) the rotor axis is kept level by a calibrated spring attached to the outer ring and the instrument case.
  • B) the inner ring is tied to the vertical by a control system.
  • C) there is only one gimbal ring.
  • D) the inner ring is pivoted laterally inside the outer ring and the outer ring is pivoted longitudinally inside the case.

  • 3) The fundamental difference between an INS and an IRS is that:
  • A) The IRS is a strap down system with 3 accelerometers mounted 90º to each other
  • B) The INS is a strap down system with 2 accelerometers mounted 90º to each other
  • C) The INS is a strap down system with 3 accelerometers mounted 90º to each other
  • D) The IRS is a strap down system with 2 accelerometers mounted 90º to each other

  • 4) The purpose of the flux-valve is:
  • A) to measure the strength of the earth's magnetic field.
  • B) to provide flux for the automatic slaving system.
  • C) to align the spokes with the earth's magnetic field in order to get maximum voltage from the pick-up coils.
  • D) to sense the direction of the earth's magnetic field relative to the airplane.

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  • 4) The purpose of the flux-valve is:
  • A) to measure the strength of the earth's magnetic field.
  • B) to provide flux for the automatic slaving system.
  • C) to align the spokes with the earth's magnetic field in order to get maximum voltage from the pick-up coils.
  • D) to sense the direction of the earth's magnetic field relative to the airplane.

  • 5) In a left turn, the ball of the turn co-ordinator is out to the right, what corrective action is required?
  • A) more left rudder.
  • B) decrease elevator pitch.
  • C) more right bank.
  • D) more left bank.

  • 6) A DGI has:
  • A) one degree of freedom & a vertical spin axis.
  • B) two degrees of freedom & a horizontal spin axis.
  • C) one degree of freedom & a horizontal spin axis.
  • D) two degrees of freedom & a vertical spin axis.

  • 7) The case of an air driven turn and balance indicator is leaking. A rate 1 turn of 360° will take:
  • A) Less than two minutes
  • B) More than two minutes
  • C) None of the above
  • D) Two minutes exactly

  • 8) In a Gyro magnetic Compass the flux gate transmits information to the:
  • A) heading indicator.
  • B) amplifier.
  • C) erecting system.
  • D) error detector.

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  • 9) Typical directional gyro indicator errors are:
  • A) random wander, gimballing errors and apparent wander due to earth's rotation.
  • B) gimballing errors, position error and friction error.
  • C) instrument error, synchro error and wandering errors.
  • D) parallax errors and gimballing errors.

  • 10) The flux valve in a RIMC:
  • A) is supplied with AC current.
  • B) is fed with DC current.
  • C) is made of hard-iron magnetic steel.
  • D) has its own self exciter unit.

  • 11) (Refer to figure 022-09)�The attached diagram shows a gyro-stabilized platform. 1 is a .... gyro gimbal and 2 is a .... gyro gimbal.
  • A) ROLL ; PITCH
  • B) PITCH ; YAW
  • C) ROLL ; YAW
  • D) PITCH ; ROLL

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  • 12) The sustained oscillation in the Ring Laser Gyro (RLG) is initially caused by:
  • A) the spontaneous return of photons to a higher energy level, which in turn produces, excited neon atoms.
  • B) the corner mirrors, which reflect the radiation energy, back to the photons.
  • C) 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.
  • D) the pressure fluctuation in the high pressure mixture of helium and neon gases in the triangular cavity.

  • 13) A tied gyro has .... (i) planes of freedom and is always controlled in .... (ii) of these planes by .... (iii):
  • A) (i) 3 (ii) at least one (iii) an external force
  • B) (i) 2 (ii) both (iii) gravity
  • C) (i) 3 (ii) only one (iii) gravity
  • D) (i) 3 (ii) both (iii) an external force

  • 14) 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?
  • A) 30°
  • B) 15°
  • C) 10°
  • D) 20°

  • 15) What indications should you get from the turn-and-slip indicator during taxi?
  • A) the ball stays fixed in the centre position during the turn, and the needle deflects in the opposite direction of the turn
  • B) the ball stays fixed in the centre position during the turn, and the needle deflects in the direction of the turn
  • C) the ball moves freely opposite the turn, and the needle deflects in the direction of the turn
  • D) the ball moves freely in the direction of the turn, and the needle deflects in the opposite direction of the turn

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  • 16) The purpose of the slaving torque motor is:
  • A) to produce a precessive force in order to align the gyro with the earth's magnetic field
  • B) to produce a precessive force in order to align the gyro with the vertical plane
  • C) to take inputs from the flux valve and apply appropriate correction to the gyro
  • D) to produce a precessive force in order to align the gyro with the horizontal plane

  • 17) In a Slaved Gyro Compass System the output of the flux-valve is fed to:
  • A) the slaving torque motor directly.
  • B) to the power supply of the gyro unit.
  • C) to the indicator.
  • D) the stator in the slaved gyro control.

  • 18) The amber ALERT light on an INS control and display unit:
  • A) flashes for 2 minutes before reaching the next way point
  • B) illuminates steadily for 2 minutes before reaching the next way point
  • C) illuminates if power from the aircraft bus bar has been lost and the system is operating on standby battery
  • D) illuminates steadily after passing a way point in manual mode, until the next leg is programmed in

  • 19) An INS with the accelerometers aligned N/S and E/W is limited to use at latitudes below about 82° . This is because:
  • A) at high speed on East or West tracks the rate of convergence is faster than the azimuth motor can correct
  • B) the correction for the Coriolis effect of earth rotation approaches infinity above 82° lat
  • C) it loses horizontal reference as dip becomes large
  • D) the functions of Secant Latitude and Tangent Latitude used for certain corrections in the computer start to approach infinity and the computer cannot handle the rapid changes involved

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  • 20) The characteristics of the directional gyro (DG) used in a gyro stabilised compass system are:
  • A) one degree of freedom, whose horizontal axis is maintained in the horizontal plane by an automatic erecting system.
  • B) two degrees of freedom, whose axis aligned with the vertical to the location is maintained in this direction by an erecting system.
  • C) two degrees of freedom, whose horizontal axis corresponding to the reference direction is maintained in the horizontal plane by an automatic erecting system.
  • D) one degree of freedom, whose vertical axis, aligned with the real vertical to the location is maintained in this direction by an automatic erecting system.

  • 21) What is known as the " Schuler Period" has a length of:
  • A) 84.4 hours.
  • B) 84.4 minutes.
  • C) 84.4 seconds.
  • D) 84.4 Hertz.

  • 22) Assume a perfectly frictionless DI is corrected to give zero drift on the ground at 30° N. The DI is set to read 270° in an aircraft tracking along the 60° parallel at a groundspeed of 545 knots. The DI reading after 80 minutes:
  • A) 257.33°
  • B) 254.66°
  • C) 286.80°
  • D) 283.66°

  • 23) The indication of the directional gyro as an on-board instrument are valid only for a short period of time. The causes of this inaccuracy are:
  • The earth's rotation
  • The longitudinal acceleration
  • The aircraft's motion over the surface of the earth.
  • The mechanical defects of the gyro
  • The gyro's weight
  • The gimbal mount of the gyro rings
  • The combination of correct statements is:
  • A) 1,2,3,4,5,6.
  • B) 1,3,4.
  • C) 1,3,4,6.
  • D) 2,5,6.

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  • 24) The rotational speed of an air-driven gyro is normally:
  • A) 9000 - 12000 RPM
  • B) 14000 - 16000 RPM
  • C) 4400 - 4600 RPM
  • D) 6000 - 9000 RPM

  • 25) The corrections fed to the platform gimbal motors of a north referenced inertial navigation system during the ALIGN mode use inputs from:
  • A) the latitude setting, the accelerometers
  • B) the longitude setting, the latitude setting, the air data computer
  • C) all the above
  • D) the latitude setting, the longitude setting, the accelerometers

  • 26) Erection systems are provided for the purpose of:
  • A) Erecting and maintaining the gyro in its vertical position
  • B) Aligning a directional gyro in its vertical position
  • C) Aligning a directional gyro in its horizontal position
  • D) Erecting and maintaining the gyro in its horizontal position

  • 27) The rotational speed of the gyro in a rate of turn indicator is .... (i) than in the direction indicator to .... (ii):
  • A) (i) Higher (ii) reduce apparent wander
  • B) (i) Higher (ii) increase rigidity
  • C) (i) Lower (ii) increase the resultant precessional force
  • D) (i) Lower (ii) reduce rigidity

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  • 28) When an aircraft has turned 270 degrees with a constant attitude and bank, the pilot observes the following on a classic artificial horizon:
  • A) too much nose up and bank to high.
  • B) attitude and bank are correct.
  • C) too much nose up and bank correct.
  • D) too much nose up and bank to low.

  • 29) A directional gyro is:
  • a gyroscope free around two axis
  • a gyroscope free around one axis
  • capable of self- orientation around an earth-tied direction
  • incapable of self-orientation around an earth-tied direction
  • The combination which regroups all of the correct statements is:
  • A) 1 - 4.
  • B) 2 - 3.
  • C) 2 - 4.
  • D) 1 - 3.

  • 30) The heading information originating from the gyromagnetic compass flux valve is sent to the:
  • A) erector system.
  • B) error detector.
  • C) heading indicator.
  • D) amplifier.

  • 31) An aircraft is flying a rate 1 turn at 480 kt TAS. What is the diameter of the turn?
  • A) 5 NM
  • B) 2 NM
  • C) 3 NM
  • D) 6 NM

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  • 32) At the second state of integration E/W speed is converted into E/W distance gone. To convert this departure into change of longitude it has to:
  • A) be multiplied by Cosine of the latitude
  • B) be divided by Tangent of the latitude
  • C) be multiplied by Secant of the latitude
  • D) be divided by Secant of the latitude
  • 33) The rate gyro indicates the correct rate of turn when the rate of .... (i) precession due to the spring is .... (ii) to the .... (iii) rate of turn:
  • A) (i) secondary (ii) equal (iii) aircraft
  • B) (i) secondary (ii) opposite (iii) aircraft
  • C) (i) primary (ii) balanced by and equal (iii) aircraft
  • D) (i) torque (ii) opposite (iii) primary

  • 34) The rotational speed of the gyroscope in a turn indicator falls below the correct operational speed. A 90° turn at an indicated RATE ONE on this turn indicator will take:
  • A) 30 seconds ± 10 seconds either way
  • B) less than 30 seconds
  • C) more than 30 seconds
  • D) 30 seconds

  • 35) What is the Schuler period?
  • A) 21 minutes.
  • B) 84 minutes.
  • C) 63 minutes.
  • D) 1 oscillation in azimuth.

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  • 36) Alignment of a RLG INS takes:
  • A) 15 – 20 minutes
  • B) 84.4 minutes
  • C) 10 – 15 minutes
  • D) Less than 10 minutes

  • 37) A longitude error in an INS will cause:
  • A) Will be corrected for once the E/W accelerometer has aligned to true north
  • B) A failure to align
  • C) Poor alignment and degraded accuracy
  • D) Will cause no problems at all

  • 38) An airborne instrument, equipped with a gyro with 1 degree of freedom and a horizontal spin axis is a:
  • A) gyromagnetic compass.
  • B) directional gyro.
  • C) fluxgate compass.
  • D) turn indicator.

  • 39) The heading read on the dial of a directional gyro is subject to errors, one of which is due to the movement of the aircraft. This error...
  • A) is dependent on the ground speed of the aircraft, its true track and the average latitude of the flight.
  • B) shows itself by an apparent rotation of the horizontal axis of the gyroscope which seems to turn at 15° per hour to the right in the northern hemisphere.
  • C) is, in spite of this, insignificant and may be neglected.
  • D) is at its greatest value when the aircraft follows a meridional track.

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  • 40) The control and display unit of an inertial navigation system indicates a position of 4810.9° N 00012.2° W on a ramp position 4807.5° N 00005.1° E. What is the radial error rate of the system if it has been in NAV mode for 8 hours 20 minutes:
  • A) 14.3 NM/hr
  • B) 1.37 Km/hr
  • C) 1.37 NM/hr
  • D) 11.42 NM/hr

  • 41) The directional gyro keeps its rotation axis aligned toward:
  • A) magnetic North.
  • B) a point on the Earth's surface.
  • C) geographic North.
  • D) a point in space.

(Refer to figure 022-08)�42) The diagram representing a left turn with insufficient rudder is:

  • A) 1
  • B) 2
  • C) 3
  • D) 4

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  • 43) A turn and balance indicator uses a:
  • A) Space gyro
  • B) Tied gyro
  • C) Rate gyro
  • D) Earth gyro
  •  44) Among the systematic errors of the " directional gyro" , the error due to the earth rotation make the north reference turn in the horizontal plane. At a mean latitude of 45° N, this reference turns by...
  • A) 7.5° /hour to the left
  • B) 15° /hour to the right
  • C) 7.5° /hour to the right
  • D) 10.5° /hour to the right

45) What is an operational difference between the turn coordinator and the turn and slip indicator?

  • A) the turn coordinator indicates roll rate, rate of turn, and co-ordination; the turn and slip indicator indicates rate of turn and co-ordination.
  • B) the turn coordinator indicates bank angle only; the turn and slip indicator indicates rate of turn and co- ordination.
  • C) the turn coordinator is always electric; the turn and slip indicator is always vacuum-driven.
  • D) the turn coordinator indicates angle of bank; the turn-and-slip indicator indicates turn rate in co-ordinated flight.

  • 46) What is the main cause of precession?
  • A) Magnetic declination.
  • B) Magnetic variation.
  • C) Bearing friction.
  • D) The Earth's rotation.

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  • (Refer to figure 022-25)�47) The turn and slip and artificial horizon shown in attached figure show the aircraft to be turning left at rate one:
  • A) with too much bank and nose below the horizon
  • B) slipping in with nose below the horizon
  • C) with insufficient bank and nose above the horizon
  • D) and skidding out with nose below the horizon

  • 48) The operational limits of a typical air driven direction indicator:
  • A) are due to the air jets being attached to the inner gimbal ring
  • B) are 85° in roll and pitch
  • C) are overcome by twin air jets
  • D) are not restrictive to heading

  • 49) The basic properties of a gyroscope are:
  • A) Torque and inertia
  • B) Rigidity and inertia
  • C) Precession and torque
  • D) Precession and rigidity

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  • 50) The operating principle of the pendulous vane unit erecting system is:
  • A) The influence of gravity on the gyro rotors.
  • B) The influence of gravity on the pendulous vanes.
  • C) The influence of gravity on the pendulous vanes and the gyro rotors.
  • D) The air flow reaction through the open vanes.

  • 51) The term 'toppling', when applied to gyros is:
  • A) gyroscopic precession.
  • B) real wander and apparent wander.
  • C) wander in the vertical plane.
  • D) wander in the horizontal plane.

  • 52) Gimballing error:
  • A) will be zero on only two headings during a 360° turn.
  • B) will remain until the gyro is reset.
  • C) will disappear after a turn is completed.
  • D) will only occur during a 360° turn.

  • 53) The purpose of the caging knob (Directional Gyro) is:
  • A) to prevent apparent wander.
  • B) to reset the heading.
  • C) to reset the heading and to prevent toppling.
  • D) to prevent the gyro toppling.

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  • 54) Deviation compensation in a flux gate compass is done:
  • A) Both mechanically and electronically
  • B) Electronically
  • C) By the pilot
  • D) Mechanically

  • 55) The acceleration errors of en electrical artificial horizon are reduced compared to those of an air driven one by:
  • A) spinning the electrical rotor slower
  • B) the use of compensation stilts
  • C) reducing the erection rate of the gyro assembly
  • D) designing the gyro so that it is not pendulous

  • 56) The torque motor of a gyro stabilised magnetic compass:
  • A) moves the Selsyn stator.
  • B) precesses the directional gyro.
  • C) takes its input from the flux valve.
  • D) moves the heading pointer.

  • 57) A turn indicator is an instrument which indicates rate of turn. Rate of turn depends upon:
  • bank angle
  • aeroplane speed
  • aeroplane weight
  • The combination regrouping the correct statements is:
  • A) 1 and 2.
  • B) 1, 2, and 3.
  • C) 2 and 3.
  • D) 1 and 3.

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  • 58) When an aircraft has turned 90 degrees with a constant attitude and bank, the pilot observes the following on a classic artificial horizon:
  • A) too much nose-up and bank correct.
  • B) too much nose-up and bank too high.
  • C) too much nose-up and bank too low.
  • D) attitude and bank correct.

  • 59) The maximum drift error sensed by an uncompensated DGI will be:
  • A) 60 deg per hour.
  • B) 45 deg per hour.
  • C) 15 deg per hour.
  • D) 30 deg per hour.

  • 60) Where is the earth rate wander, and the transport wander of a gyro equal to zero?
  • A) 45 N.
  • B) North Pole.
  • C) 45 S.
  • D) Equator.

  • 61) 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:
  • A) with damping and a period of about 84 seconds
  • B) without damping and a period of about 84 seconds
  • C) with damping and a period of about 84 minutes
  • D) without damping and a period of about 84 minutes

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  • 62) The errors of an INS fall into 3 categories:
  • A) Bounded, unbounded and inherent
  • B) Bounded, unbounded and velocity
  • C) Bounded, unbounded and accelerometer
  • D) Coriolis, unbounded and inherent

  • 63) What is the Schuler period?
  • A) 84 seconds.
  • B) 48 seconds.
  • C) 84 minutes.
  • D) 48 minutes.

  • 64) The pendulum type detector system of the directional gyro feeds:
  • A) a levelling erection torque motor.
  • B) a nozzle integral with the outer gimbal ring.
  • C) 2 torque motors arranged horizontally.
  • D) a torque motor on the sensitive axis.

  • 65) A DGI is assumed to be frictionless. Its latitude nut is set for 56° N. The reading that you would expect to see after flying West along the parallel of 48° N for 45 minutes at a TAS of 480 kts with a Wind velocity of 090/60 would be:
  • A) 278.5°
  • B) 281.3°
  • C) 261.3°
  • D) 277.6°

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  • 66) A Stand-by-horizon or emergency attitude indicator:
  • A) Is automatically connected to the primary vertical gyro if the alternator fails.
  • B) Only works of there is a complete electrical failure.
  • C) Contains its own separate gyro.
  • D) Is fully independent of external energy resources in an emergency situation.

  • 67) A turn indicator is built around a gyroscope with:
  • A) 0 degree of freedom.
  • B) 3 degrees of freedom.
  • C) 2 degrees of freedom.
  • D) 1 degree of freedom.

  • 68) An artificial horizon with an electrical driven gyroscope has greatly reduced take-off errors. This is because:
  • A) the gyro has greater rigidity, is less bottom heavy and there is a linear accelerometer cut-out switch fitted
  • B) the gyro has greater rigidity, is less bottom heavy and there is a roll cut-out switch fitted
  • C) the fast erection switch is used to overcome topple by increasing the erection rate to a high value
  • D) it is fitted with a roll cut-out switch and a linear cut-out switch

  • 69) With reference to Inertial Navigation Systems, the functions of the integrators are:
  • at the second stage of integration to suppress unbounded errors (when in the NAV mode)
  • at the first stage of integration to convert acceleration, with respect to time, into speed, (when in the NAV mode)
  • at the second stage of integration to convert speed, with respect to time, into distance gone, (when in the NAV mode).
  • to align the platform (when in the level and align modes)
  • A) only (2) and (3) of the above statements are true
  • B) only (1), (2) and (3) of the above statements are true
  • C) all the above statements are true
  • D) only (2), (3) and (4) of the above statements are true

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  • 70) The basic properties of a gyroscope are:
  • The gyro's weight
  • The rigidity in space
  • The inertia
  • The high RPM
  • The precession
  • The combination of correct statements is:
  • A) 2, 3, 5
  • B) 2, 5
  • C) 1, 3, 5
  • D) 3, 4

  • 71) A slaved directional gyro derives it's directional signal from:
  • A) a direct reading magnetic compass
  • B) the flight director
  • C) the flux valve
  • D) the air-data-computer

  • 72) When decelerating in an aircraft with an air driven artificial horizon you would expect to see:
  • A) A climbing turn to starboard
  • B) A descending turn to port
  • C) A descending turn to starboard
  • D) A climbing turn to port

  • 73) A gyromagnetic compass or heading reference unit is an assembly which always consists of:
  • a directional gyro
  • a vertical axis gyro
  • an earth's magnetic field detector
  • an azimuth control
  • a synchronising control
  • The combination of correct statements is:
  • A) 1,4.
  • B) 2,3,5.
  • C) 1,3,5.
  • D) 2,5.

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  • 74) A standby artificial horizon must have the following properties:
  • a remote gyro
  • its own power supply
  • only to be used in emergency
  • its own gyro
  • one for each certified pilot
  • A) all the above
  • B) 1,3, & 5
  • C) 2, 3, & 4
  • D) 2 & 4

  • 75) Rigidity in a gyroscope is:
  • A) a way to express the stability of the inner and outer gimbal rings.
  • B) the reaction 90° in the direction of rotation when applying force to the spinning wheel.
  • C) to what extremes the flight attitudes might be before the gyro topples.
  • D) the tendency it has to remain in its plane of rotation and resist attempts to alter its position.

  • 76) Apparent wander of a gyro is caused by:
  • A) rotation of the earth.
  • B) clear air turbulence.
  • C) gimbal friction.
  • D) external torque.

  • 77) In a turn at constant angle of bank, the rate of turn is:
  • A) independent of weight and inversely proportional a to TAS.
  • B) dependant on weight and proportional to TAS.
  • C) dependant on weight and inversely proportional to TAS.
  • D) independent of weight and proportional a to TAS.

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  • 78) When using an INS platform Coriolis affects:
  • A) Neither a nor b
  • B) The N/S accelerometer
  • C) Both a & b
  • D) The E/W accelerometer

  • 79) The gyromagnetic compass torque motor:
  • A) feeds the error detector system.
  • B) causes the directional gyro unit to precess.
  • C) causes the heading indicator to precess.
  • D) is fed by the flux valve.

  • 80) The properties of a Turn Indicator are:
  • One degree of freedom
  • two degrees of freedom
  • two springs connected to the aircraft frame
  • spin axis in the longitudinal plane
  • spin axis parallel to the yaw axis
  • spin axis in the lateral plane
  • A) 1, & 6
  • B) 2, & 5
  • C) 1, & 4
  • D) 2, & 6

  • 81) The input signal of the amplifier of the gyromagnetic compass resetting device originates from the:
  • A) directional gyro unit.
  • B) flux valve.
  • C) directional gyro erection device.
  • D) error detector.

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  • 82) When, in flight, the needle and ball of a needle-and-ball indicator are on the left, the aircraft is:
  • A) turning left with not enough bank.
  • B) turning right with not enough bank.
  • C) turning right with too much bank.
  • D) turning left with too much bank.

  • 83) While flying, a red flag labelled " HDG" appears in the indicator (HSI) of a Slaved Gyro Compass System. This indicates that:
  • A) The flux valve has detected an error between the actual aircraft heading and the pre-selected heading
  • B) The autopilot has detected an error between the actual aircraft heading and the pre-selected heading
  • C) The flux valve is not supplying reliable information to the compass system
  • D) None of the above

  • 84) Apparent drift in a direction indicator is:
  • A) 7 1/2° /hour at 30° N and 30° S, and zero at the equator.
  • B) non-existent at all latitudes because of the drift-nut attached to one of the gimbals.
  • C) 15° /hour at the equator and zero at the poles.
  • D) 7 1/2° /hour at 30° N and 30° S, and zero at the poles.

  • 85) The latitude nut of the direction indicator is on the .... (i) gimbal and this causes the gyro to precess around its .... (ii) axis:
  • A) (i) outer (ii) horizontal
  • B) (i) outer (ii) vertical
  • C) (i) inner (ii) horizontal
  • D) (i) inner (ii) vertical

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  • 86) In a DGI what error is caused by the gyro movement relative to the earth?
  • A) latitude error.
  • B) real wander.
  • C) transport Wander.
  • D) earth Rate.

  • 87) The torque motor of a slaved gyro compass:
  • A) precesses the gyro in the vertical plane.
  • B) precesses the gyro in the horizontal plane.
  • C) moves the heading pointer.
  • D) moves the Selsyn stator.

  • 88) The rotor spinning axis of the electrically driven artificial horizon is erected and maintained vertical by:
  • A) commutator switches
  • B) the fast erection device
  • C) mercury switches
  • D) the pendulosity of the rotor assembly

  • 89) You are at 30° N flying on a northerly heading. Your DI reading will:
  • A) decrease at an increasing rate
  • B) increase at a decreasing rate
  • C) increase at an increasing rate
  • D) decrease at a decreasing rate

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  • 90) In order to align a strapdown inertial unit, it is requited to insert the local geographical coordinates. This is necessary to:
  • A) Check operation of laser gyros
  • B) Re-erect laser gyros
  • C) Determine magnetic or true heading
  • D) Position the computing trihedron with reference to earth

  • 91) If a 180º steep turn is made to the right and the aircraft is rolled out to straight and level flight by visual reference, the miniature aircraft on the Attitude Indicator will...
  • A) show a slight slip and descent to the right.
  • B) show a slight climb and turn to the right.
  • C) show a slight skid and climb to the right.
  • D) show a slight climb and turn to the left.

  • 92) On the ground, during a left turn, the turn indicator indicates:
  • A) needle to the left, ball to the right.
  • B) needle to the left, ball to the left.
  • C) needle in the middle, ball to the right.
  • D) needle in the middle, ball to the left.

  • 93) When an aircraft has turned 360 degrees with a constant attitude and bank, the pilot observes the following on a classic artificial horizon:
  • A) attitude and bank correct.
  • B) too much nose-up and bank too high.
  • C) too much nose-up and bank correct.
  • D) too much nose-up and bank too low.

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  • 94) Following 180° stabilized turn with a constant attitude and bank, the artificial horizon indicates:
  • A) too high pitch-up and correct banking.
  • B) too high pitch up and too high banking.
  • C) attitude and banking correct.
  • D) too high pitch-up and too low banking.

  • 95) While accelerating on take-off, what would be the expected indications on an electrically driven Attitude Indicator?
  • A) none of the above - it will indicate correctly
  • B) a climbing turn to the left
  • C) a climbing turn to the right
  • D) a descending turn to the left

  • 96) During an acceleration phase at constant attitude, the resetting principle of the artificial horizon results in the horizon bar indicating a:
  • A) nose-down followed by a nose-up attitude.
  • B) nose-up attitude.
  • C) constant attitude.
  • D) nose-down attitude.

  • 97) Air-driven gyro rotors are prevented from spinning too fast by the:
  • A) electronic speed regulator module
  • B) vacuum relief valve
  • C) pressure outflow valve
  • D) pressure reducing valve

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  • 98) An aircraft is flying at a TAS of 270 knots. What AOB will give a rate 1 turn:
  • A) 17°
  • B) 30°
  • C) 34°
  • D) 15°

  • 99) Why is an INS platform virtually unusable at very high latitudes?
  • A) The value of earth rate affecting the E/W accelerometer is a component dependent on the sine Lat. At high latitudes this component is nearly zero and makes alignment to magnetic north virtually impossible
  • B) The value of earth rate affecting the E/W accelerometer is a component dependent on the cosine Lat. At high latitudes this component is nearly zero and makes alignment to true north virtually impossible
  • C) The value of earth rate affecting the E/W accelerometer is a component dependent on the sine Lat. At high latitudes this component is nearly zero and makes alignment to true north virtually impossible
  • D) The value of earth rate affecting the E/W accelerometer is a component dependent on the cosine Lat. At high latitudes this component is nearly zero and makes alignment to magnetic north virtually impossible

  • 100) If the needle and the ball of a Turn & Slip indicator both show right, what does it indicate:
  • A) turn to right & too little bank.
  • B) turn to right & too much bank.
  • C) turn to left & too much bank.
  • D) turn to left & too little bank.

  • 101) In a turn and slip indicator, the gyro is spinning at a greater speed than normal. What will the effect be on the indicated rate of turn?
  • A) It will cause more precision and rigidity.
  • B) It will be more accurate than usual.
  • C) It will underread.
  • D) It will overread.

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  • 102) What are the advantages of a laser gyro compared to a conventional gyro?
  • A) uses more power.
  • B) takes longer to set up/ spin up.
  • C) takes longer to align.
  • D) has a longer cycle life.

  • 103) If an INS platform is not accurately aligned with true north:
  • A) The N/S accelerometer will sense an acceleration force caused by the rotation of the earth
  • B) The E/W accelerometer will sense an acceleration force caused by the rotation of the earth
  • C) The E/W accelerometer will sense a velocity force caused by the rotation of the eart
  • D) The N/S accelerometer will sense a velocity force caused by the rotation of the earth

  • 104) Which of the following is true regarding the turn co-ordinator?
  • A) Its gyro is offset by 300 to the longitudinal axis of the aircraft
  • B) It has a tied gyroscope
  • C) It responds to rate of turn only
  • D) It gives angle of bank and rate of turn

  • 105) When, in flight, the needle of a needle-and-ball indicator is on the left and the ball on the right, the aircraft is:
  • A) turning right with not enough bank
  • B) turning left with too much bank
  • C) turning left with not enough bank
  • D) turning right with too much bank

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  • 106) The principle of operation of the turn and slip indicator is best described as:
  • A) a single gimbal gyroscope in which a spring, opposing the primary precession, in turn produces a secondary precession equal to the aircraft rate of turn
  • B) a space gyro which uses the force of precession against a spring to give a reading of the aircraft rate of turn
  • C) a single gimbal gyroscope whose primary precession is opposed by a spring which, in turn, produces a second precession equal and opposite to the aircraft rate of turn
  • D) an earth gyro in which a calibrated spring ensures the tilt of the gyro is proportional to the aircraft rate of turn

  • 107) The inertial platform in a north-referenced inertial navigation system is torqued to perform like a Schuler pendulum, so that when the platform moves over the earth:
  • A) answers b and c are correct
  • B) the platform remains level and aligned regardless of any aircraft accelerations
  • C) gyro drift errors are cancelled out
  • D) the platform will always oscillate with respect to true north

  • 108) The triangular cavity in a RLG is filled with which combination of gases:
  • A) Helium and neon
  • B) Helium and argon
  • C) Hydrogen and argon
  • D) Hydrogen and neon

  • 109) The inner gimbal assembly of an artificial horizon is pivoted .... (i) in the .... (ii):
  • A) (i) laterally (ii) case
  • B) (i) longitudinally (ii) outer gimbal
  • C) (i) to give freedom (ii) pitch plane
  • D) (i) longitudinally (ii) rolling plane

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  • 110) A gravity erector system is used to correct the errors on:
  • A) a directional gyro.
  • B) an artificial horizon.
  • C) a gyromagnetic compass.
  • D) a turn indicator.

  • 111) The heading reference unit of a three-axis data generator is equipped with a gyro with:
  • A) 1 degree of freedom and horizontal spin axis.
  • B) 2 degrees of freedom and vertical spin axis.
  • C) 2 degrees of freedom and horizontal spin axis.
  • D) 1 degree of freedom and vertical spin axis.

  • 112) An aircraft initiates a rate one turn at a TAS of 270 kt. How far will it have travelled after 25 seconds:
  • A) 1.96 NM
  • B) 5.88 NM
  • C) 3.92 NM
  • D) 7.84 NM

  • 113) The rate-of-turn is the:
  • A) aircraft speed in a turn.
  • B) pitch rate in a turn.
  • C) change-of-heading rate of the aircraft.
  • D) yaw rate in a turn.

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  • 114) The position accuracy of an RLG INS is:
  • A) 1 NM/hr
  • B) 5 NM/hr
  • C) 10 NM/hr
  • D) 2 NM/hr

  • 115) A laser gyro consists of:
  • A) 2 electrodes (anodes + cathodes).
  • B) a gyro with 2 degrees of freedom.
  • C) two moving cavities provided with mirrors.
  • D) a laser generating two light waves.

  • 116) An IRS with laser gyros should (i) .... be Schuler tuned, and (ii) .... be strapped down.
  • A) (i) never (ii) always
  • B) (i) never (ii) never
  • C) (i) always (ii) never
  • D) (i) always (ii) always

  • 117) A failed RMI rose is locked on 090° and the ADF pointer indicates 225° . The relative bearing to the station is:
  • A) 135° .
  • B) 315° .
  • C) Impossible to read, due to failure RMI.
  • D) 225° .

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  • 118) What is the maximum drift of a gyro, due to earth rate:
  • A) 90 deg per hour.
  • B) 15 deg per hour.
  • C) 180 deg per hour.
  • D) 5 deg per hour.

  • 119) With regard to the turn indicator, the spring:
  • A) Produces a secondary precession that opposes yaw
  • B) Directly balances yaw
  • C) Gives a linear relationship between extension and secondary force
  • D) Produces a secondary precession equal to yaw

  • 120) A space gyro has .... (i) gimbal rings with .... (ii) planes of freedom:
  • A) (i) 3 (ii) 3
  • B) (i) 2 (ii) 3
  • C) (i) 3 (ii) 2
  • D) (i) 2 (ii) 2

  • 121) If a turn and balance indicator overspeed the result will be:
  • A) The rate of turn will be indicated correctly
  • B) Under-indication of the turn
  • C) No turn will be indicated
  • D) Over-indication of the turn

  • 122) An aircraft is flying along the 60° S parallel. After one hour the DI indication has increased by 21° . If the latitude nut of the DI has been set to zero drift on the ground at 30° S, the groundspeed of the aircraft is:
  • A) 473
  • B) 537
  • C) 450
  • D) 520

  • 123) Laser gyros are used in an IRS. Why must accurate Lat & Long be inserted?
  • A) to determine the computed trihedron
  • B) to check the function of the laser gyros
  • C) to determine magnetic north
  • D) to compensate for aircraft movement

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  • 124) 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)
  • A) two degrees of freedom, whose horizontal axis corresponding to a reference direction is maintained in a horizontal plane by an automatic erecting system.
  • B) two degrees of freedom, whose axis is oriented and continuously maintained to local vertical by an automatic erecting system.
  • C) one degree of freedom, whose horizontal axis is maintained in a horizontal plane by an automatic erecting
  • D) 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.

  • 125) In a right turn while taxiing, the correct indications on a Turn & Slip Indicator are:
  • A) Needle right, ball left.
  • B) Needle left, ball left.
  • C) Needle right, ball right.
  • D) Needle left, ball right.

  •  126) When, in flight, the needle and ball of a needle-and-ball indicator are on the right, the aircraft is:
  • A) turning right with not enough bank.
  • B) turning right with too much bank.
  • C) turning left with too much bank.
  • D) turning left with not enough bank.

  • 127) At a low bank angle, the measurement of rate-of-turn actually consists in measuring the:
  • A) pitch rate of the aircraft
  • B) roll rate of the aircraft
  • C) angular velocity of the aircraft
  • D) yaw rate of the aircraft

  • 128) The rotor in an electric artificial horizon is tied to the vertical by:
  • A) a jet of air from the rotor impinging on a wedge plate which is on the inner gimbal
  • B) a jet of air from the outer gimbal striking the rotor buckets
  • C) mercury switches only
  • D) torque motors and level switches

  • 129) In a turn at constant rate, the turn indicator reading is:
  • A) proportional to the aircraft true airspeed.
  • B) inversely proportional to the aircraft true airspeed.
  • C) independent to the aircraft true airspeed.
  • D) proportional to the aircraft weight.

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  • 130) In a left turn while taxiing, the correct indications are:
  • A) Needle right, ball left.
  • B) Needle left, ball left.
  • C) Needle left, ball right.
  • D) Needle right, ball right.
  • (Refer to figure 022-29)
  • 131) The turn and slip and artificial horizon illustrated in the attached figure show the aircraft to be turning:
  • A) left with skid
  • B) right with insufficient bank and the nose above the horizon
  • C) right at 30 degrees angle of bank with slip
  • D) right at 30 degrees angle of bank with skid

  • 132) The vertical reference unit of a three-axis data generator is equipped with a gyro with:
  • A) 1 degree of freedom and horizontal spin axis
  • B) 2 degrees of freedom and vertical spin axis
  • C) 2 degrees of freedom and horizontal spin axis
  • D) 1 degree of freedom and vertical spin axis

  • 133) The turn rate indicator uses a gyroscope:
  • with one degree of freedom.
  • with two degrees of freedom
  • the frame of which is supported by two return springs.
  • the spinning wheel axis of which is parallel to the pitch axis.
  • the spinning wheel axis of which is parallel to the yawing axis.
  • the spinning wheel axis of which is horizontal.
  • The combination regrouping all the correct statements is:
  • A) 2, 3 and 6
  • B) 2 and 3
  • C) 1 and 6
  • D) 1, 3, and 6

  • 134) The gimbal error of the directional gyro is due to the effect of:
  • A) a bank or pitch attitude of the aircraft.
  • B) an apparent weight and an apparent vertical.
  • C) too slow precession on the horizontal gimbal ring.
  • D) the aircraft's track over the earth.

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  • 135) An aircraft is flying at a 120 kt true airspeed (VV), in order to achieve a rate 1 turn, the pilot will have to bank the aircraft at an angle of:
  • A) 30° .
  • B) 12° .
  • C) 18° .
  • D) 36° .

  • 136) A 2 axis gyro measuring vertical changes will have:
  • A) one degree of freedom vertical axis.
  • B) two degrees of freedom vertical axis.
  • C) two degrees of freedom horizontal axis.
  • D) one degree of freedom horizontal axis.

  • 137) The rigidity of a gyro is improved by:
  • A) increasing RPM and concentrating the mass on the periphery of the rotor.
  • B) decreasing RPM and concentrating the mass at the hub of the rotor.
  • C) decreasing RPM and concentrating the mass on the periphery of the rotor.
  • D) increasing RPM and concentrating the mass at the hub of the rotor.

  • 138) In the building principle of a gyroscope, the best efficiency is obtained through the concentration of the mass:
  • A) close to the axis and with a high rotation speed..
  • B) on the periphery and with a high rotation speed.
  • C) close to the axis and with a low rotation speed..
  • D) on the periphery and with a low rotation speed..

  • 139) Failure of the electrical supply to an electrically driven direction indicator may be indicated by:
  • A) Low suction.
  • B) A low ammeter reading.
  • C) A red warning flag.
  • D) A low voltmeter reading.

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  • 140) Which of the following statements is most correct when describing a turn co-ordinator?
  • A) It indicates the angle of bank and turn rate.
  • B) It is suitable for a stand-by artificial horizon.
  • C) It responds to aircraft bank angle as well as turning rate.
  • D) It displays turn and pitch for a rate one turn only.

  • 141) A rate integrating gyro is a detecting element used in
  • An inertial attitude unit
  • An automatic pilot
  • A stabilizing servo system
  • An inertial navigation system
  • A rate-of-turn indicator
  • The combination of correct statements is:
  • A) 2,3,4.
  • B) 2,3,5.
  • C) 1,4.
  • D) 1,2,3,4,5.

  • 142) Concerning the directional gyro indicator, the latitude at which the apparent wander is equal to 0 is:
  • A) the equator.
  • B) latitude 30° .
  • C) the North pole.
  • D) latitude 45° .

  • 143) In a turn indicator, the measurement of rate of turn consists for:
  • A) high bank angle, in measuring the roll rate
  • B) low bank angle, in measuring the yaw rate
  • C) low bank angle, in measuring the roll rate
  • D) high bank angle, in measuring the yaw rate

  • 144) The directional gyro axis no longer spins about the local vertical when it is located:
  • A) in the latitude 45° .
  • B) in the latitude 30° .
  • C) on the North pole.
  • D) on the equator.

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  • 145) Which of the following are errors of a DGI:
  • earth rate
  • transport wander
  • banking when pitched up
  • annual movement of poles
  • mechanical problems
  • A) 1, 2, 3, & 5
  • B) 3, 4, & 5
  • C) all 5
  • D) 2, 3, & 5

  • 146) The forces which affect the balance ball in a turn and slip indicator are:
  • A) weight, lift vector and TAS.
  • B) weight and centrifugal force.
  • C) centripetal force, attitude and weight.
  • D) weight and centripetal force.
  • 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.

  • 147) Chose the combination with true statements only:
  • A) 1,2,3,5.
  • B) 3,4,5.
  • C) 2,3,5.
  • D) 1,2,4,5.

  • 148) When turning left on the ground the turn and slip indicator:
  • A) will show a skid
  • B) will show a left bank and slip
  • C) will show a left bank and skid
  • D) will not indicate on the ground