INS/IRS/FMS - Dgca question bank for pilots

Results

#1. Gyro compassing of an Inertial system (IRS) is accomplished with the mode selector switched to?

ALIGN

STBY

NAV

ATT REF

#2. Which of the following lists all of the methods that can be used to enter ‘Created Waypoints’ into the CDU of a B737 – 400 Electronic Flight Instrument System?

Identifier range, location name; Height above MSL; latitude and longitude.

Identifier bearing/distance; place bearing/place bearing; along-track displacement; latitude and longitude.

Identifier name and range; location name; Height above MSL; latitude nd longitude.

Identifier grid reference, location name, Height above MSL, latitude and Rhumb line position.

#3. Some Inertial reference and navigation system are known as “strapdown”. This means that?

The accelerometers are fixed to the aircraft structure but the gyros are stabiised.

The gyros are stabilised but the accelerometers are fixed to the aircraft structure.

The gyroscopes and accelerometers become part of the unit's fixture to the aircraft structure.

The indicator units are strapped to the aircraft structure.

#4. As the INS position of the departure aerodrome, coordinates 35°32,7’N 139°46.3’Ware input instead of 35°32.7’N 139°46.3’E. When the aircraft subsequently passes point 52°N 180°W, the longitude value shown on the INS will be?

099° 32.6'E

099° 32.6'W

199° 32.6'W

299° 32.6'W

#5. In order to maintain an accurate vertical using a pendulous system, an aircraft Inertial platform incorporates a device?

With damping and a period of 84.4 MIN

With damping and a period of 84.4 SEC.

With damping and a period of 48.4 MIN

With damping and a period of 48.4 SEC

#6. In what way does IRS differ from INS?

Has a shorter spin-up time and suffers from laser lock

Does not need to correct for coriolis and central acceleration

Has a longer spin-up time and is not affected by vertical acceleration due to gravity.

Does not experience Schuler errors as accelerometers are strapped down.

#7. Which of the following statements is true of a Ring Laser Gyro?

It is not necessarily fixed to true north and is quick to erect

It is fixed to true north and is quick to erect

If doesn't suffer from 'lock in' and is unaffected by the earth's gravitational force

It is not necessarily fixed to true north but takes along time to erect

#8. In a laser reference system (IRS), are compared to a gyro reference system (INS):

The accelerometers are strapped down but the platform is gyro stabilised.

Accelerometers and platform are both strapped down.

The platform is strapped down but the accelerometers are gryo-stabilised.

Accelerometers and platform are both gyro-stabilised.

#9. In a ring laser gyro, the purpose of the dither motor is to:

Compensate for transport wander.

Stabilise the laser frequencies

Enhance the accuracy of the gyro at all rotational rates

Overcome laser rock

#10. A pilot turns off the power to his IRS whilst in flight. He switches it on again after just a few seconds. What will be the effect?

It can be repositioned whilst in flight

There will be no effect

It cannot be used and must be shut down

It cannot be used for navigation, but can be used provide attitude information

#11. In which IRS mode does gyro-compassing takeplace?

ATT

ALIGN

NAV

#12. A gyro is said to drift when its spin axis moves in the ?

Horizontal and vertical

Neither, because its definition is not related to these

Horizontal

Vertical

#13. What do the sensors of an INS measure?

Acceleration

The horizontal component of the earth's rotation

Velocity

Precession

#14. The IRS position is updated?

Updating is normally carried out by the crew when position (VOR station or NDB)

IRS positions are updated by pressing the 'Take-off at the start of the take-off roll

During flight IRS position are automatically updated

Only on the ground during the alignment proceudre.

#15. Some Inertial reference systems are known as ‘strapdown’

The system is mounted on a stabilised platform

The gyros are fixed but the accelerometers are stable

The system is mounted and fixed to the aircraft strap

The accelerometers are fixed but the gyros are stable

#16. Double Integration of the output from the east/west accelerator navigation system(INS) in the NAV MODE given:

Vehicle longitude

Distance east/west

Distance north/south

Velocity east/west

#17. The principle of ‘Schuler Tuning’ as applied to the operation of Inertial Navigation Systems/Inertial Reference Systems is applicable to:

Only gyro-stabilised systems

Both gyro-stabilised platform and strapdown systems.

Both gyro-stabilised and laser gyro systems but only when operating in the non 'strapdown' mode.

Only to 'strapdown' laser gyro systems.

#18. In an Inertial Navigation system (INS), what is the output of the first stage North/South Integator?

Velocity along the local meridian

Groundspeed

Latitude

Change of latitude

#19. Alignment of INS and IRS equipments can take place in which of the following modes?

ALING only

ALING and ATT

ATT and ALIGN

NAV and ALIGN

#20. On a triple-fit IRS system, present positions on the CDU?

Are likely to differ as the information comes from different sources

Will only differ if one IRS has been decoupled due to a detected malfunction.

Will only differ if an Initial input error of aircraft position has been made

Will not differ as the information is averaged

#21. What are the positions (In the order left to right) on the Boeing 737 – 400 IRS Mode Selector Unit (MSU)?

OFF STBY ATT NAV

OFF ALIGN NAV ATT

OFF STBY NAV ATT

OFF STBY ALIGN NAV

#22. Gyro – compassing in an INS?

It is not possible in flight because the gyros cannot differentiate between acceleration due to aircraft movement and initial alignment errors.

d. Is possible in flight as he gyros cannot differentiate between acceleration due to aircraft movement and Initial alignment error.

Is possible in flight as the gyros can differentiate between acceleration due to aircraft movement and initial alignment errors.

Is not possible in flight as the gyros can differentiate between acceleration due to aircraft movement and Initial alignment errors.

#23. In an INS/IRS, an azimuth gyro is found to have a drift rate. If t is the time since selecting the MSU from ALIGN to NAV the szimuth gyro heading error is?

Proportional to t

Proportional to the square root of t

Proportional to t/2

Sinusoidal

#24. On the IRS, selection of ATT mode gives attitude?

Altitude, and heading.

Only.

And heading,.

Heading, and groundspeed.

#25. How long does it take to align an IRS (Laser Ring Gyros)?

1 minute

5 minutes

10 minutes

15 minutes

#26. What is the purpose of the plezo-electric motor in an IRS system?

Dither

Vibrate

Shake

Shudder

#27. In order to maintain an accurate vertical using a pendulous system, an Aircraft inertial platform incorporates a device?

Without damping and a period of 84.4 MIN

Without damping and a period of 84.4 SEC

With damping and a period of 84.4 MIN

With draping and a period of 84.4 SEC

#28. The platform of an Inertial navigation system (INS) is maintained at right angles to the local vertical by applying corrections for the effects of?

Aircraft manoeuvres, earth rotation, transport wander and coriollis

Movement in the yawing plane, secondary procession and pendulous oscillation

Gyroscopic Inertia, earth rotation and real drift

Vertical velocities, earth procession, centrifugal forces and transport drift

#29. In an Inertial Navigation System (INS), Ground Speed (GS) is calculated?

By Integrating gyro precession in N/S and E/W directions respectively.

From TAS and WN from Air Data Computer (ADC)

By integrating measured acceleration

From TAS and WN from RNAV data

#30. An aircraft equipped with an Inertial Navigation System (INS) files with INS 1 coupled with autopilot. 1. Both inertial navigation systems are navigating from way-point A to B. The inertial systems’ Central Display Units (CDU) show: XTK on INS 1 = 0 XTK on INS 2 =8 L (XTK = cross track) What can be deduced from this information?

Only Inertial navigation system No. 1 is drifting

At least one of the inertial navigation systems is drifting

Only Inertial navigation system No. 2 is drifting

The autopilot is unserviceable in NAV mode

#31. If an IRS loses its position mid-flight it must?

Not be used in NAV mode

Be turned OFF

Have a new position inserted

Be selected to ALIGN and then to NAV

#32. What does INS need for wind calculations?

EAS

TAS

Mach Number

Heading

#33. What do you call a system of gyros and accelerometers that is fixed to the aircraft?

Laser

Stabilised

Fixed

Strapdown

#34. When is the last point at which an INS or IRS may be selected to NAV mode?

After passengers and freight are aboard.

Immediately prior to push back or taxi from the gate

At the holding point

On operation of TOGA switch when opening the throttles for the take-off

#35. In what form are positions entered in all INS systems?

Geographic coordinates

Ranges and bearings

Waypoint names

Hexadecimals

#36. Which mode selection on the CDU of an INS is required to display Initial Great Circle track?

HDG/DA

DSRTK/STS

TK/DS

XTK/TKE

#37. An IRS differs from an INS in that it?

Has a longer spin-up time and is not affected by vertical accelerations due to gravity

Does not need to correct for coriolis and central acceleration

Does not experience Schuler errors as accelerometers are strapped down

Has a shorter spin-up time and suffers from laser lock

#38. Which of the following statements is true of a Ring Laser Gyro?

It doesn't suffer from 'lock in' and is unaffected by the earth's gravitational force

It is not necessarily fixed to the true north but takes long time to erect

It is not necessarily fixed to true north and is quick to erect

It is fixed to true north and is quick to erect

#39. In a laser reference system (IRS), as compared to a gyro reference system (INS)

The accelerometers are strapped down but the platform is gyro stabilised

Accelerometers and platform are both strapped down

The platform is strapped down but the accelerometers are gyro-stabilsed

Accelerometers and platform are both gyro-stabilsed

#40. The dither motor in a ring laser gyro sis used to?

Compensation for transport wander

Stabilise the laser frequencies

Enhance the accuracy of the gyro at all rotational rates

Overcome laser lock

#41. A pilot turns off his IRS whilst in flight, then switches it on again after just a few seconds. What will be the effect?

It can be repositioned whilst in flight

There will be no effect

It cannot be used and must be shut down

It cannot be used for navigation, but can be used to provide attitude information

#42. In which IRS mode does gyro-compassing take place?

ATT

ALIGN

NAV

#43. Gyro drift occurs when the spin axis moves in the?

Horizontal and vertical

Neither, because its definition is not related to these axes

Horizontal

Vertical

#44. What do the sensors of an INS measure?

Acceleration

The horizontal component of the earth's rotation

Velocity

Precession

#45. Where and when are the IRS positions updated?

During flight IRS positions are automatically updated by the FMC

Only on the ground during the alignment procedure

Updating is normally carried out by the crew when over-flying a known position (VOR station or NDB)

IRS positions are updated by pressing the 'Take-off/Go-around' button at the start of the take-off roll

#46. Some Inertial reference systems are known as ‘strapdown’. This means:

The system is mounted on a stabilised platform

The gyros are fixed but the accelerometers are stabilised

The system is mounted and fixed to the aircraft structure

The accelerometers are fixed but the gyros are stabilised

#47. What is produced by double Integration of the output from the east/west accelerometer of an inertial navigation system (INS) when it is in the NAV MODE?

Distance north/south

Velocity east/west

Vehicle longitude

Distance east/west

#48. The principle of ‘Schuler Tuning’ as applied to the operation of Inertial Navigation Systems/Inertial Reference Systems is applicable to:

Only gyro-stabilised systems

Both gyro-stabilised platform and strapdown systems

Both gyro-stabilised and laser gyro systems but only when operating in the non 'strapdown' mode.

Only to 'strapdown' laser gyro systems

#49. In an Inertial Navigation System (INS), what is the output of the first stage North/South integrator?

Velocity along the local meridian

Groundspeed

Longitude

Change of latitude

#50. Alignment of INS and IRS equipments can take place in which of the following modes?

ATT and ALIGN

NAV and ALIGN

ALIGN only

ALIGN and ATT

#51. On an aircraft equipped with a triple-fit IRS system, present positions on the CDU?

Will only differ if an initial input error of aircraft position has been made

Will not differ as the information is averaged

Are likely to differ as the information comes from different sources

Wlli only differ if one IRS has been decoupled due to a detected malfunction

#52. What are the positions (in the order left to right) on the Boeing 737-400 IRS Mode Selector Unit (MSU)?

OFF STBY ATT NAV

OFF STBY NAV ATT

OFF STBY ALIGN NAV

OFF ALIGN NAV ATT

#53. Gyro-compassing in an INS?

It is not possible in flight because the gyros cannot differentiate between acceleration due to aircraft movement and initial alignment errors

It is possible in flight as the gyros cannot differentiate between acceleration due to aircraft movement and initial alignment errors

Is possible in flight as the gyros can differentiate between acceleration due to aircraft movement and initial alignment errors.

Is not possible in flight as the gyros can differentiate between acceleration due to aircraft movement and initial alignment errors.

#54. If t is the time since selecting the MSU from ALIGN to NAV the azimuth gyro heading error caused by drift rate of an INS/IRS azimuth gyro is?

Proportional to t/2

Sinusoidal

Proportional to t

Proportional to the square root of t

#55. On the IRS, selection of ATT mode gives attitude?

Altitude, and heading

Only

And heading

Heading and groundspeed

#56. How long does it take to align an IRS (Laser Ring Gyros)?

10 minutes

15 minutes

1 minute

5 minute

#57. What principle is utilized by the plezo-electric motor in an IRS system?

Shake

Shudder

Dither

Vibrate

#58. By what means in an accurate vertical maintained using a pendulous system, an aircraft Inertial platform Incorporates a device?

With damping and a period of 84.4 MIN

With damping and a period of 84.4 SEC

Without damping and period of 84.4 MIN

Without damping and a period of 84.4 SEC

#59. In an Inertial Navigation System(INS), Ground Speed (GS) is calculated?

By integrating gyro precession in N/S and E/W directions respectively

From TAS and WN from Air Data Computer (ADC)

By integrating measured acceleration

From TAS and WN from RNAV data

#60. An aircraft equipped with an Inertial Navigation System (INS) files with INS 1 coupled with autopilot. Both Inertial navigation systems are navigating from waypoint A to B. The Inertial systems ‘Central Display Units (CDU) show? XTK on INS 1 = 0 XTK on INS 2 = 15L (XTK = cross track) What can be deduced from this information?

Only Inertial navigation system No. 1 is drifting

Only Inertial navigation system No. 2 is drifting

The autopilot is unserviceable in NAV mode

At least one of the Inertial navigation systems is drifting

#61. If an IRS loses its position mid-flight it must?

Not be used in NAV mode

Be turned OFF

Have a new position inserted

Be selected to ALIGN and then to NAV

#62. The platform of an inertial navigation system (INS) is maintained at right angles to the local vertical by applying corrections to counter the effects of?

Gyroscopic Inertia, earth rotation and real drift

Vertical velocities, earth precession, centrifugal forces and transport drift

Aircraft manoeuvres, earth rotation, transport wander and coriolis

Movement in the yawing plane, secondary precession and pendulous oscillation

#63. What does INS need for wind calculation?

EAS

TAS

Mach Number

Heading

#64. What do you call a system of gyros and accelerometers that is fixed to the aircraft?

Laser

Stabilised

Fixed

Strapdown

#65. The latest point at which an INS or IRS may be selected to NAV mode is?

At the holding point

On operation of TOGA switch when opening the throttles for the take-off

After passengers and freight are aboard

Immediately prior to push back or taxi from the gate

#66. What format is used to enter positions into INS systems?

Waypoint names

Hexadecimais

Ranges and bearings

Geographic coordinates

#67. Which mode on the CDU of an INS must be selected in order to display Initial Great Circle track?

DSRTK/STS

TK/GS

XTK/TKE

HDG/DA

#68. When can a pilot change the data in the FMS database?

Every 28 days

When it is deemed to be necessary

When there is a fruit

Never, because the FMS database is read-only

#69. The FMC position is?

The average of the IRS positions

Computer generated from the radio navigation positions

Half way between the IRS and radio navigation positions

Computer generated from the IRS and radio navigation positions

#70. What is the source of magnetic variation information in a Flight Management System (FMS)?

The main directional gyro, which is coupled to the magnetic sensor (flux valve) positioned in the wingtip

The FMS calculates MH and MT from the FMC position

Magnetic variation information is stored in each IRS memory; it is applied to the true heading calculated by the respective IRS

Magnetic variation is calculated by each IRS based on the respective IRS position and the aircraft magnetic heading

#71. What are, in order of highest priority followed by lowest, the two levels of message produced by the CDU of the B737-400 Electronic Flight Instrument System?

Warning nd Advisory

Caution and Advisory

Urgent and Routine

Warning and Caution

#72. In the B737-400 Flight Management System the CDUs are used during preflight to?

Manually initialise the IRSs and FMC with dispatch information

Manually initialise the IRS, FMC and Authorities with dispatch information

Automatically initialise the IRSs and FMC with dispatch information

Manually initialise the Flight Director System and FMC with dispatch information

#73. The FMS on a 737-400 provides?

Automatic navigation & manual performance management

Automatic navigation & automatic performance management

Manual navigation & manual performance management

Manual navigation & automatic performance management

#74. What is the sequence of pages on start-up of the Boeing 737-400 FMS?

POS, INIT, IDENT, DEPARTURES

IDENT, POS INIT,RTE

POST INIT, RTE, IDENT

IDENT, POS INIT, DEPARTURES

#75. FMC aircraft position determined by radio navigation is derived on the B737-400 FMS from?

VOR/DME

DME/ADF

VOR/VOR

DME/DME

#76. When initial position is put into a B737-400 FMS, the system?

Rejects initial latitude error, but it will accept longitude error

Rejects initial longitude error, but it will accept latitude error

Rejects initial latitude or longitude error

Cannot detect input errors, and accepts whatever is put in

#77. The period of validity of an FMS database is?

56 days

One week

28 days

Variable

#78. On the Boeing 737-400 EFIS EHSI, on which modes is a Weather Radar Display available?

MAP, PLAN, FULL VOR/ILS

MAP, PLAMN, EXP VOR/ILS

MAP, EXP VOR/ILS, EXP NAV

MAP, FULL VOR/ILS, FULL NAV

#79. In what formats can created waypoints be entered into the scratch pad of the B737-400 FMS?

Place Bearing/Distance, Place Bearing/Place Bearing, Along-Track Displacement, Latitude and Longitude

Place Bearing/Distance, Place Distance/Place Distance, Along-Track Displacement, Latitude and Longitude

Place Bearing/Distance, Place Bearing/Place Bearing, Across-Track Displacement, Latitude and Longitude

Place, Place Bearing/Distance, Along-Track Displacement, Latitude and Longitude

#80. Which EFIS symbol below represents the selected course?

#81. How does the FMS calculate groundspeed?

Input from DME with change of range integrated with respect to time

Input of heading from either the IRS or gyro compass, TAS from ADC and wind velocity from selected metrological data

Input from IRS

Input from ADC of TAS and wind velocity

#82. When can a pilot change the data in the FMS database?

When there is a fault

Never, because the FMS database is read-only

Every 28 days

When it is deemed to be necessary

#83. How is the FMC position produced?

The average of the IRS position

Computer generated from the IRS and radio navigation positions

Computer generated from the radio navigation positions

Half way between the IRS and radio navigation positions

#84. From what source does an FMS obtain magnetic variation information?

Magnetic variation information is stored in each IRS memory; it is applied to the true heading calculated by the respective IRS

Magnetic variation is calculated by each IRS based on the respective IRS position and the aircraft magnetic heading

The main directional gyro which is coupled to the magnetic sensor (flux valve) positioned in the wingtip

The FMS calculates MH and MT from the FMC positions.

#85. What are, in order of highest priority followed by lowest, the two levels of message produced by the CDU of the B737-400 EFIS?

Caution and Advisory

Urgent and Routine

Warning and Caution

Warning and Advisory

#86. The CDUs in the B737-400 Flight Management System are used during preflight to?

Manually initialise the IRSs and FMC with dispatch information

Manually initialise the IRSs, FMC and Authorities with dispatch information

Automatically initialise the IRSs and FMC with dispatch information

Manually initialise the Flight Director System and FMC with dispatch information

#87. The Boeing 737-400 Flight Management System (FMS) provides?

Manual navigation & manual performance managment

Manual navigation & automatic performance managment

Automatic navigation & manual performance management

Automatic navigation & automatic performance managment

#88. List the sequence of pages on start-up of the Boeing 737-400 FMS?

IDENT, POS INIT, RTE

POS, INIT, RTE, IDENT

IDENT, POS INIT, DEPARTURES

POS INIT, IDENT, DEPARTURES

#89. In the Boeing 737-400 aircraft the FMC aircraft position determined by radio navigation is derived from?

DME/DME

VOR/DME

DME/ADF

VOR/VOR

#90. When aligning the B737-400 FMS, the system?

Rejects initial latitude or longitude error

Cannot detect input errors, and accepts whatever is put in

Rejects initial latitude error, but it will accept longitude error

Rejects initial longitude error, but it will accept latitude error

#91. What is the period of validity of an FMS databse?

56 days

One week

28 days

Variable

#92. In what modes is the Weather Radar Display available on EFIS EHSI?

MAP, EXPVOR/ILS, EXP NAV

MAP, FULLVOR/ILS, FULL NAV

MAP,PLAN, FULL VOR/ILS

MAP, PLAN, EXP VOR/ILS

#93. In what formats can created waypoints be entered into the scratch pad of the B737-400 FMS?

Place Bearing/Distance, Place Distance/Place Distance, Along-Track Displacement, Latitude and Longitude

Place Bearing/Distance, Place Bearing/Place Bearing, Across-Track Displacement, Latitude and Longitude

Place, Place Bearing/Distance, Along-Track Displacement, Latitude and Longitude

Place Bearing/Distance, Place Bearing/Place Bearing, Along-Track Displacement, Latitude and Longitude

#94. Which EFIS symbol below represents the Trend vector?

#95. What information is required by the FMS to enable it to calculate groundspeed?

Input from IRS

Input from ADC of TAS and wind velocity

Input from DME with change of range integrated with respect to time

Input of heading from either the IRS or gyro compass, TAS from ADC and wind velocity from selected meterological data

#96. Which FMC/CDU page normally appears on initial power application to the B737-400 Electronic Flight Instrument System?

IDENT

POS INIT

PERF INIT

RTE

#97. Which of the following lists the first three pages of the FMC/CDU normally used to enter data on initial start-up of the B737-400 Electronic Flight Instrument System?

POS INIT - IDENT - RTE

RTE - POS INT - IDENT

IDENT - POS INIT - RTE

PERF INIT - POD IDENT - INIT

#98. A pilot accidentally turning OFF the INS in flight, and then turns it back ON a few moments later. Following this incident?

It cannot be used for the remainder of the flight

It can only be used for attitude reference

It must be switched off or its gyros will apple

It can be used as normal

#99. If an INS temporarily loses its power supply in flight?

It will functions normally

It will be usable only in the NASV mode

It must be switched off for the remainder of the flight

It can only be used for attitude reference

#100. The sensors of an INS measure?

Position

Acceleration

Velocity

TAS

#101. Waypoints can be entered in an INS memory in different formats. In which of the following formats can waypoints be entered into all INS systems?

Grid references

Airport names

Geographic coordinates

Index numbers

#102. An aircraft equipped with an Inertial Navigation System (INS) flies with INS 1 coupled with autopilot 1. Both inertial navigation systems are navigating from waypoint A to B. The inertial systems’ Central Display units (CDU) shows. XTK on INS 1 = 0, XTK on INS 2 = 10L (XTK = cross track). What can be deduced from this information?

Both systems are drifting

Both systems are serviceable as this error is within limits

The INS2 is drifting

At least one of the inertial navigation systems is drifting

#103. How often can a pilot update the data in the FMS database?

Every 28 days

When it is deemed to be necessary

When there is a fruit

Never, because the FMS database is read-only

#104. From what information is the FMC position calculated?

Computer generated from the IRS and radio navigation positions

The average of the IRS positions

Computer generated from the radio navigation positions

Half way between the IRS and radio navigation positions

#105. How does an FMS obtain magnetic variation information?

The main directional gyro, which is coupled to the magnetic sensor (flux valve) positioned in the wingtip

The FMS calculates MH and MT from the FMC positions

Magnetic variation is calculated by each IRS based on the respective IRS position and the aircraft magnetic heading

Magnetic variation information is stored in each IRS memory; it is applied to the true heading calculated by the respective IRS

#106. What is the highest priority and lowest priority, message produced by the CDU of the B737-400 EFIS?

Caution and Advisory

Warning and Advisory

Urgent and Routine

Warning and Caution

#107. What is the function of the MCDUs in the B737-400Flight Management System when carrying out preflight checks?

Manually initialise the IRSs,FMC and Authorities with dispatch Information

Automatically initialise the IRSs and FMC with dispatch information

Manually initialise the Flight Director System and FMC with dispatch information

Manually initialise the IRSs and FMC with dispatch information

#108. The functions of the Boeing 737-400 FMS include?

Automatic navigation & automatic performance management

Manual navigation & manual performance management

Manual navigation & automatic performance management

Automatic navigation & manual performance management

#109. In a Boeing 737-400 FMS the sequence of pages on start-up is?

POS INIT, IDENT, DEPARTURES

IDENT, POS INIT, RTE

IDENT, POS INIT, DEPARTURES

INIT, POS, RTE, IDENT

#110. From what source is the FMC aircraft position determined by radio navigation in the Boeing 737-400 aircraft derived?

VOR/DME

DME/DME

DME/ADF

VOR/VOR

#111. When the Boeing B737-400 FMS is being initialized prior to flight, the system?

Rejects initial latitude error, but it will accept longitude error

Cannot detect input errors, and accepts whatever is put in

Rejects initial longitude error, but it will accept latitude error

Rejects initial latitude or longitude error

#112. For how long does the data in the FMS database remain valid?

56 days

One week

28 days

Variable

#113. Weather radar Displays are available on the Boeing 737-400 EFIS EHSI, when the system is set to?

MAP, PLAN, FULL VOR/ILS

MAP, PLAN, EXP VOR/ILS

MAP, EXPVOR/ILS EXP NAV

MAP, FULL VOR/ILS, FULL NAV

#114. In what formats can created waypoints be entered into the scratch pad of the B737-400 FMS?

Place Bearing/Distance, Place Bearing/Place Bearing, Across-Track Displacement, Latitude and Longitude

Place, Place Bearing/Distance, Along-Track Displacement, Latitude and Longitude

Place Bearing/Distance, Place Bearing/Place Bearing, Along-Track Displacement, Latitude and Longitude

Place Bearing/Distance, Place Distance/Place Distance, Along-Track Displacement, Latitude and Longitude

#115. Which white EFIS symbol below represents the aircraft?

#116. How does the FMS calculate groundspeed?

Input from IRS

Input from ADC of TAS and wind velocity

Input from DME with change of range integrated with respect to time

Input of heading from either the IRS or gyro compass, TAS from ADC and wind velocity from selected metrological data

#117. In what way does IRS differ from INS?

Has a longer spin-up time and is not affected by vertical accelerations due to gravity

Does not experience Schuler errors as accelerometers are strapped down

Has a shorter spin-up time and suffers from laser lock

Does not need to correct for coriolis and central acceleration

#118. A Ring Laser Gyro?

It is fixed to true north and is quick to erect

It doesn't suffer from 'lock in' and is unaffected by the earth's gravitational force

It is not necessarily fixed to true north but takes along time to erect

It is not necessarily fixed to true north and is quick to erect

#119. In a laser reference system(IRS), as compared to a gyro reference system (INS):

The accelerometers are strapped down but the platform is gyro stabilised

Accelerometers and platform are both strapped down

The platform is strapped down but the accelerometers are gyro-stabilised

Accelerometers and platform are both gyro-stabilised

#120. In a ring laser gyro, the purpose of the dither motor is to:

Compensate for transport wander

Stabilise the laser frequencies

Enhance the accuracy of the gyro at all rotational rates

Overcome laser lock

#121. What will be the effect if the crew of an aircraft switch off the power to his IRS whilst in flight, before switching it back on a few seconds later?

It cannot be used for navigation, but can be used to provide attitude information

It must be re-aligned whilst in flight

The system will operate normally

It cannot be used and must be shut down or the gyros will topple

#122. In which IRS mode does gyro-compassing take place?

ATT

ALIGN

NAV

#123. In which plane must the spin axis move to cause a gyro to drift?

Horizontal

Vertical

Horizontal and Vertical

Neither, because its definition is not related to these axes

#124. What do the sensors of an INS measure?

Acceleration

The horizontal component of the earth's rotation

Velocity

Precession

#125. Where and when are the IRS positions updated?

Only on the ground during the alignment procedure

Updating is normally carried out by the crew when over-flying a known position (VOR station or NDB)

During flight IRS positions are automatically updated by the FMC

IRS positions are updated by pressing the 'Take-off/Go-around' button at the start of the take-off roll

#126. Some inertial reference systems are known as ‘strapdown’. This means:

The system is mounted on a stabilised platform

The gyros are fixed but the accelerometers are stabilised

The system is mounted and fixed to the aircraft structure

The accelerometers are fixed but the gyros are stabilised

#127. What output is calculated by double integration of output from the east/west accelerometer of an inertial navigation system (INS) when the system is engaged in the NAV mode?

Vehicle longitude

Distance east/west

Distance north/south

Velocity east/west

#128. The principle of ‘Schuler Tuning’ as applied to the operation of Inertial Navigation Systems/Inertial Reference Systems is applicable to:

Only gyro-stabilised systems

Both gyro-stabilised platform and strapdown systems

Both gyro-stabilised and laser gyro systems but only when operating in the non 'strapdown' mode

Only to 'strapdown' laser gyro systems

#129. In an Inertial Navigation System(INS), the output of the first stage North/South integrator is?

Velocity along the local meridian

Groundspeed

Latitude

Change of latitude

#130. Alignment of INS and IRS equipments can take place in which of the following modes?

ALIGN only

NAV and ALIGN

ALIGN and ATT

ATT and ALIGN

#131. When a triple-fit system is employed, the present positions on the CDU?

Will only differ if one IRS has been decoupled due to a detected malfunction

Will only differ if an inertial input error of aircraft position has been made

Will not differ as the information is averaged

Are likely to differ as the information comes from different sources

If you have 3 different IRSs, each will have slightly different errors (for instance, slightly
different initial alignments, slightly different laser gyro wander rates, etc) which will
result in slightly different computations of IRS position

#132. What are the positions(in the order left to right) on the Boeing 737-400 IRS Mode Selector Unit (MSU)?

OFF ALIGN NAV ATT

OFF STBY ATT NAV

OFF STBY NAV ATT

OFF STBY ALIGN NAV

#133. In an INS the process of gyro-compassing?

Is possible in flight as the gyros can differentiate between acceleration due to aircraft movement and initial alignment errors.

Is not possible in flight as the gyros can differentiate between acceleration due to aircraft movement and initial alignment errors

It is not possible in flight because the gyros cannot differentiate between acceleration due to aircraft movement and initial alignment errors

Is possible in flight as the gyros cannot differentiate between acceleration due to aircraft movement and initial alignment errors.

#134. If an INS/IRS, an azimuth gyro is found to be drifting in flight, and it t is the time since selecting the system from ALIGN to NAV, the azimuth gyro heading error will be?

Proportional to the square root of t

Proportional to t/2

Sinusoidal

Proportional to t

#135. On the IRS, selection of ATT mode gives attitude?

Altitude and heading

Only

Heading and groundspeed

And heading

#136. How much time is required to align an Inertial Reference System?

1 minute

5 minute

10 minute

15 minutes

#137. What principle is utilized by employing a plezo-electric motor to overcome laser lock in an IRS system?

Shake

Shudder

Dither

Vibrate

#138. In order to maintain an accurate vertical using a pendulous system, an aircraft inertial platform incorporates a device?

Without damping and a period of 84.4 MIN

Without damping and a period of 84.4 SEC

With damping and a period of 84.4 MIN

With damping and a period of 84.4 SEC

#139. In order to keep the platform of an inertial navigation system (INS) at right angles to the local vertical in flight, corrections must be applied to compensate for?

Aircraft manoeuvres, earth rotation, transport wander and coriolis

Vertical velocities, earth precession, centrifugal forces and transport drift

Movement in the yawing plane, secondary precession and pendulous oscillation

Gyroscopic inertia, earth rotation and real drift

#140. An Inertial Navigation System (INS), calculates Ground Speed (GS)?

From TAS and WN from Air Data Computer (ADC)

By integrating gyro precession in N/S and E/W directions respectively

By integrating measured acceleration

From TAS and WN from RNAV data

#141. An aircraft equipped with an Inertial Navigation System (INS) files with INS 1 coupled with autopilot 1. Both Inertial navigation systems are navigating from waypoint A to B. The inertial systems ‘Central Display Units (CDU) show: XTK on INS 1 = 12 L XTK on INS 2 = 0(XTK = cross track) What can be deducted from this information?

Only Inertial navigation system no. 1 drifting

At least one of the Inertial navigation systems is drifting

Only Inertial navigation system No.2 is drifting

The autopilot is unserviceable in NAV mode

#142. After an IRS has lost its position mid-flight it must?

Not be used in NAV mode

Be turned OFF

Have a new position inserted

Be selected to ALIGN and then to NAV

#143. What does INS need for wind calculation?

EAS

TAS

mach Number

Heading

#144. What do you call a system of gyros and accelerometers that is fixed to the aircraft?

Laser

Stabilised

Fixed

Strapdown

#145. What is the latest time at which the INS/IRS may be selected to NAV mode?

After passengers and freight are aboard

Immediately prior to push back or taxi from the gate

On operation of the TOGA switch when opening the throttles for the take-off

At the holding point

#146. What can be used to enter positions on all INS systems?

Waypoint names

Hexadecimals

Geographic coordinates

Ranges and bearing

#147. The INS CDU mode selection required to display Initial Great Circle track is?

HDG/DA

TK/GS

XTK/TKE

DSRTK/STS

#148. Which Cyan symbol below represents an off-route waypoint?

#149. Which of the following lists all of the methods that can be used to enter ‘Created Waypoints’ into the CDU of a B737-400 Electronic Flight Instrument System?

Identifier name and range; location name; Height above MSL; latitude and longitude

Identifier grid reference, location name, Height above MSL, latitude and Rhumb line position

Identifier range, location name; Height above MSL; latitude and longitude

Identifier bearing/distance; place bearing/place bearing; along-track displacement; latitude and longitude

#150. Some Inertial reference and navigation systems are known as “strapdown”. This means that?

The gyroscopes and accelerometers become part of the unit's fixture to the aircraft structure

The indicator units are strapped to the aircraft structure

The accelerometers are fixed to the aircraft structure but the gyros are stabilised

The gyros are stabilised but the accelerometers are fixed to the aircraft structure

Finish