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Landing Gear

17 to 20 and they are not braked

1. What wheels do body steering


2. How many gear door opening handles are there

Electrically only

3. How are the gear doors opened and uplocks released

"16, all WLG axles and fwd 4 axles on each BLG"

4. How many brake units are fitted to the A380

"Pedals, Autobrakes, Landing gear lever (spin brakes)"

5. What are the normal input commands for normal braking


6. Which CPIOM’s control the landing gear

All 16

7. If an engine run is being actioned how many brakes are applied by the park brake

"A pump, ECU and a reservoir with no accumulator. There are 3 in total for NWS, wing and body brakes"

8. What's contained in the LEHGS unit

Cargo door opening via green system EMP’s normally

9. What will the green system automatically activated for

NWS is commanded +-6 deg

10. How does the autopilot steer down the runway

Body wheel steering is commanded from nose wheel steering. That happens from 14deg and is commanded from 20deg

11. What steering inputs does the body gear steering get

"Never, the alternate refill vlv's are only there for topping up the accumulators on gnd prior to flight"

12. Will the ARV’s open inflight

-15 degs (when one side goes to +15 degs the other will only go to +11 degs and vice-verca in the opposite direction to the NLG)

13. What is the maximum movement of the body gear steering

"3 groups, wing group, left body group and right body group"

14. How many groups of braking are there

6 degrees

15. How many degrees NWS can the rudder pedals input

"4 – 2 in forward cargo, 2 in aft cargo."

16. How many L/G RDC’s are there? Where located

"Mechanically released, electrically made."

17. How do the landing gear door locks operate


18. How many CPIOM-G’s are there

"Electrically released, hydraulically operated and mechanically uplocked"

19. How is the normal extension and retraction system controlled and operated

LGERS app in CPIOM-G’s.

20. Which application controls EXT/RET operational sequence

Independent prox sensors through the LGRDC’s.

21. What supplies LG position to the independent indication light and how

"Normal, alternate, emergency, ultimate and parking brake."

22. What are the 5 modes of operation for the braking system

",Yes anti-skid available. LEHGS supplies hydraulics.

23. "In alternate braking mode, is anti-skid available? What supplies hydraulics

"Does not, only available on BLG."

24. How does the parking brake mode operate on WLG

Three- one for each braking group. In main avionics

25. How many IRDC’s

Bogie shuttle valve selects highest pressure from normal and alternate circuits.

26. What component decides if normal or alternate hyd circuit operates the brakes

"Each shock absorber, 5 in total"

27. Which shock absorbers have OPTS (Oleo Pressure and Temperature Sensors) Fitted

"OPTS, pressure gauge, (setup to) h dimension (126mm) and chart"

28. What is on each oleo (shock absorber)

"On ground – cross check, in flight – accuracy check (LG fully extended) check this"

29. What type of checks will OPMS carry out on the ground? In Flight

G3 and G4

30. Which CPIOM – Gs have the OPMS application


31. Which LGRDC will the nose and L/H WLG send OPTS data to


32. Which LGRDC will L/H BLG send OPTS data to


33. Which LGRDC will R/H BLG send OPTS data to


34. Which LGRDC will R/H WLG send OPTS data to

"Will not operate in flight, operates once per flight on ground to refill LEHGS and accumulators"

35. When will the ARV (Alternate Refill Valve) open in flight and what is its function

Selector sends discrete signal to all 4 CPIOM-Gs

36. How is the landing gear selector lever signal sent to the CPIOMs and which is it sent to

Will retract into the bay rearwards

37. What direction does the BLG retract

"14 degrees unlocked, 20 degrees commanded"

38. At what NWS angle is the body steering unlocked/commanded

There are two installed in upper avionics bay

39. Where are the FFCMs (Free Fall Control Modules) fitted

","Prevents loss of hydraulic fluid, can be reset by depressurising line up stream of fuse or by pushing the manual lever on the fuse body."

40. "The BLG Bogie Trim Actuator has Fuse, what is this for and how would it be reset

"1 fitted at each BLG and WLG, position tilt for landing and gear retraction into bay"

41. What is a bogie trim actuator

Always pressurised

42. When is a bogie trim actuator pressurised

"High Velocity Oxygen Fuel, coat of tungsten carbide cobalt chromium, alternate use to chrome plating"

43. What is HVOF and what is it used for

"Outer doors only, inner door from manual procedure (remove maint panels)"

44. Which BLG gear doors open from ground door opening system

"BLG inner door normally only open in flight, to close you must install targets on BLG gear compressed/not compressed sensors"

45. When closing doors on ground what is special about closing of inner door

BLG inner and BLG centre

46. Which landing gear doors have maintenance panels

"WLG main, BLG inner"

47. Which doors have auxiliary panels

Outer door with folded centre door and inner with auxiliary door

48. What are the BLG doors

","Landing Gear Control and Indicating System, has side 1 and side 2, on side active and one side standby"

49. "What is LGCIS, how is it configured

"Side 1 and side 2, Each side has 2x CPIOM-Gs x2 LGRDCs and x1 SEPDC"

50. What does LGCIS consist of

"CPIOM-G1 and G3, LGERS app, LGRDC 4A/5A and SEPDC 1"

51. What is specifically in side 1

"CPIOM-G2 and G4, LGERS app, LGERS 4B/5B and SEPDC 2"

52. What is specifically in side 2

CPIOM-G3 (side 1) and CPIOM-G4 (side 2) (check)

53. Which CPIOMs have OPMS app

Side 1 only (LGRDCs 4A and 5A)

54. Which side will process signals for LG down locked independent prox sensors

(4A and 5A),DC ESS BUS (side 2 4B and 5B are DC2)

55. What are the power supplies for side 1 LGRDCs

On landing gear ‘UP’ selection or fault in active side

56. When will LGCIS swap over sides 1 and 2

"2x EUAs (CHA/CHB) and 1x NUA (dual motor, 1 for LGCIS#1 and 1 for LGCIS#2)"

57. What is installed at each uplock module

Door selector valve and gear selector valve

58. Which valves in LGERS belong to normal extension and retraction

Cut out (3) (norm open) and vent valves (5)

59. Which valves in LGERS belong to Free fall system

"Cutout closed, vent open"

60. In free fall configuration what are the positions of cutout and vent valve

"3, Flight (norm), close, open"

61. How many positions do the ground door operating (yellow) handles have

Elec/reset/hyd (look up function of each)

62. What are the 3 lights in handle area

Bypass valve in normal and door uplock in home position

63. If the system reset light is on what would this indicate

Door bypass valves

64. Which valves in LGERS belong to Ground door operating system


65. Which uplock actuators will the ground door operating system use

Bypass valve to half position

66. How is door closing speed controlled in the GDO system

"No, a brake wheel can be fitted to a steering wheel though"

67. Can you fit a (body) steering wheel to a braking wheel

(Brake Control System),Application in all 4 CPIOM-Gs

68. Where is BCS

Emergency mode

69. If the flight deck Anti-skid switch was set to off what braking mode would all groups be operating in

Normal and alternate BCS app in CPIOM-G along with IRDCs

70. Which braking modes are application controlled

Retraction braking

71. What functions are lost in alternate brakes

Emergency and ultimate

72. Which braking modes are EBCU controlled

Alternate circuit (LEHGS)

73. Which circuit will Emergency braking mode use

"Anti-skid, auto brake (EBCU in charge)"

74. What functions are lost in emergency braking

"Only park brake switch input to BLG (PBSELV,pk brk CCT) and EBCU input to WLG (ABSELV and ASV, alt brk CCT)"

75. What functions in ultimate braking

"Via OMS function, will fill reservoirs and accumulators from A/C hyd (x4 brake)(manual opening of ARV) note NWS LEHGS, ACCU only (reservoir is filled by return fluid)"

76. How is LEHGS manual refill performed

Inflate WLG/BLG brake ACCUs using LEHGS reservoirs fluid(x4 ACCUs) on ground

77. What does ACCU reinflate P/B do? When can it be used

Gold knob on unit (to return line)

78. How would you depressurise a LEHGS reservoir

Blue knob

79. How would you depressurise a HP accumulator

"Manual (accum reinflate P/B) and auto (accu px below threshold, 4850psi)"

80. What are the LEHGS main modes of operation

Comfort (low speed/low noise) and performance (High RPM/high noise)

81. What are the LEHGS two auto modes of operation

Will indicate the lowest value of the two body gear brake accumulators

82. What will the top needle on the triple indicator display

Will show L/H and R/H body gear alternate brake px

83. What will the lower L/H and R/H needles on the triple indicator display

SD wheels page ‘MORE’ (shows lowest px of the two)

84. Where could you view wing gear brake accumulator px

"2 accumulators, 1 accu (L/H) x4 FWD WLG brakes, 1 accu (R/H) x4 AFT WLG brakes"

85. How many WLG brake accumulators and which brake units will each run

"2 accumulators, 1 accu x4 L/H BLG brakes, 1 accu x4 R/H BLG brakes"

86. How many BLG brake accumulators and which brake units will each run

Will show ‘ACCU’ in amber on related gear diagram

87. If brake accumulators low what can SD page display

Direct discrete of 28VDC to PBSELV from park brake switch

88. What is park brake controlled by

These are apps in CPIOM-G3 and G4

89. Where are BTMS and BCS

"11degrees outboard, 15 degrees inboard"

90. Max BWS turning angles

"Towing 60degrees, hand wheel 70degrees and A/pilot or rudder 6degrees"

91. What are the NWS angles

RVDT on steering actuator

92. What is the steering angle feedback to IRDC

","Prk brake on, NWS disc fault, BWS not avail, panel on RHS of NLG"

93. "What lights are on nose wheel steering disc panel, what is location

"Flash = oversteer, steady = if NWS disconnect fault"

94. What are the meanings of NWS DISC FAULT if flashing? Steady

"At 73.5degrees, nose wheel light flash and ecam msg (75degrees = mech contact)"

95. When is over steer triggered and what will be effect

"Tow and flight, tow = green light at panel and NWS disc on ECAM EWD"

96. What are the tow switch positions and indications

It cannot be disconnected only safety pinned

97. How is BWS disconnected

(NWS),"Mechanically, closed when gear is up, shuts of hydraulic source to hydraulic block (connects hyd px to return when gear retracted)"

98. How is the swivel shut off valve operated

"Normal = NSSELV, alternate = ASSELV"

99. What will allow hydraulic fluid flow to NWS in normal mode and alternate mode

accumulator px only

100. Alternate braking but LEHGS not available is done how

"BLG (4) and WLG (4) return system located on gears themselves, they have gauges and are serviced (each main gear has 1 normal and 1 alternate LP accum)"

101. Where are the LP N2 charged accumulators


102. What hydraulics are required to close the NLG doors following maintenance

"Remove maintenance panel to prevent it hitting the wheels, ensure H dimension is greater than 126mm and turn the uplock to extend the door. To close the door target gags are required to put the a/c in the air and then yellow hydraulics close the door."

103. How do you open the BLG inner doors

"3, 1 for each LG extension system and an independent monitoring system for the flt dk lights"

104. How many prox sensors on each landing gear monitor the down and locked signal

"3 prox sensors monitor the trim bogie actuator for failure, if it fails then the prox sensor detect this and prevent gear retraction"

105. What happens if the trim bogie actuator fails


106. What is maximum steering angle from the hand wheel

From an independent prox sensor on each landing gear

107. Where is the L/G panel lights signalled from

"2, one to each system using power from the SEPDC’s"

108. How many solenoids are on the door selector valves


109. "Following a gravity extension of the landing gear, what position must the L/G GRVTY switch be put in when selecting it to off after fault isolation


110. In what unit does the antiskid live

","2 (another 2 in alternate circuit and same in BLG brakes) Nitrogen filled accumulators located in the WLG bay, painted white with a gauge and “lasts a long time!”"

111. "In the WLG brakes, what units smooth out the normal brakes in the return lines

",The ARV will open to top up the green system brake system

112. "At engine start (master switch on) and if the WLG brake sys HP accumulator is below 4800 psi, what will happen

"The LEHGS will run in comfort mode to top up the system, if that cannot be achieved then LEHGS will run in performance mode"

113. Inflight the brake system drops below 4800 psi what will happen

Reservoir is monitored by an LVDT but also has a sight glass with a ball bearing in it

114. How do we know the fluid level in the LEHGS reservoir

Door bypass vlv is in closed position and EUA-B is ready for operation

115. What does the reset light on the GDO panel mean

Tops up the LEHGS reservoir

116. Return line fluid from the NWS does what

A fucking long pole with a pin on the end is used to lock the down lock link for maintenance. An even longer red flag is positioned on the end of it with something about potatoes!

117. How is the BLG lock links safety pinned for maintenance

Flight Controls

"Short term only, THS does long term pitch control"

1. Are the elevators for short term or long term pitch control


2. The high lift function is what type of control

"1-8 Left and Right, from inboard to outboard"

3. How are the spoilers numbered

No the pitch trim switches are inhibited

4. When autopilot is engaged can the pitch trim system be moved

Normal green or yellow hydraulics with EBHA’s Electric mode as backup

5. Spoilers 5 and 6 on each side are powered by what hydraulic sources

Electric Backup Hydraulic Actuator - An amalgamation of a conventional PCU and an EHA

6. An EBHA is what


7. Where is the speedbrake function run from

7 aside (there are 8 surfaces but no.1 and no.2 surfaces inboard of the inboard engines are reffered to as no.1 Slat together)

8. How many slats are there

"8 each side, slats surfaces 1 and 2 (inboard of no.2 & 3 engines) are together called Slat 1 and operate as the droop nose function"

9. How many slat surfaces are there

The SFCC based on differential APPU signals

10. Flap asymmetry is detected by

"4, 1 between each section of flap (prox sensors)"

11. How many interconnecting struts are there

"The interconnecting flap strut section, if skew is detected then SFCC shuts down operation"

12. What detects each section of flap skew

",Damping mode

13. If an EHA is not in operation, what mode will it be in

The unit must be depressurised by pressing the depressurisation valve on the unit

14. If your changing an EHA or EBHA what must be done first

",The unit must be replaced as the accumulator Helium cannot be recharged outside of the build factory

15. "If an accumulator on an EHA, EBHA or LEHGS unit is showing as low px, what must be done

EMP’s are swapped based on flight number

16. How do the EMP’s choose which one to use which one to run

Yellow system

17. What hydraulics are required to close the body gear door after maintenance

"Information related to the body brake pressures in alternate, ultimate emergency and parking modes"

18. What does the triple gauge indicator show

Runs the WLG and BLG LEHGS to reinflate the accumulators

19. What does the ACCUS REINFLATE button do

It unlocks at 14 deg and is commanded at 20 degs

20. When does the body gear steering unlock

"6 ailerons, 16 spoilers, 1 THS, 4 elevators, 2 rudders"

21. what are the primary flight control surfaces

"4 droop noses, 12 slats, 6 flaps"

22. What are the secondary flight controls

Spoilers(4) and rudder(4)

23. Where are the EBHA’s located

Ailerons(4) and elevators(4)

24. Where are the EHA’s located

Conventional PCU

25. In normal operating mode an EBHA operates as what type of actuator

2x Droop nose slat surfaces counted as one slat for numbering

26. What type of slat is slat 1 and what is it's layout

Hydraulically normally with backup done electrically

27. How do the slats operate

It's adjusted to the feedback 0 deg position

28. How is an EHA/EBHA actuator adjusted

3 x PRIMs and 3 x SECs

29. What are the normal primary flight control computers

Computation function – outer loop and execution function – inner loop

30. What are main functions of PRIMs in flt controls

"Computation function, calculates aircraft objective for surface deflection (Active only in master PRIM) Execution function, looks after inner loop i.e. control of servo valve"

31. Explain computation function and execution function further

Will carry out rate and direction

32. What will the servo valve in a conventional servo do

"Prim 1 master, order 1,2,3"

33. In normal ops which PRIM is master? What order if failures

"Never, SECs cannot be master"

34. When will the SECs be master

"Normal law - Load factor, AOA, bank angle, high speed and pitch att prot. Alternate law - Reduced protections, are override able. Direct law - no protections"

35. What are the prim control laws and what are the protections in each

SEC would control but DIRECT LAW only

36. What would control with triple PRIM failure

X3 motors (2x hyd and 1 x elec) only 1 is in operation at any time. Will normally be green hydraulic motor

37. How many THSA motors are there and which will control in norm

Only in PRIMs

38. Where are the aux functions

"Primary = roll, Aux = Droop, LAF, lift dumping and also speedbrake (4 aux funcs)"

39. What are the aileron primary and auxiliary functions

Application within CPIOM-Cs (x2) no controlling only indication and test

40. Where is the FCDC? Main functions

Normally applied

41. What is significant regarding the WTBs

"Conventional, Hyd active and damping modes (2) EHA, Elec active and damping (2), EBHA, Elec active, Hyd active and damping (3)"

42. What are the flight control actuators and what are the modes of op

"Flap PCU, 1 green and 1 yellow hyd motor. Slat PCU, 1 green hyd and 1 elec motor"

43. What is the hyd/elec make up of flap and slat PCU motors

"Slat WTBs are elec, flap WTBs are Hyd operated"

44. What is the main difference between slat and flap WTB’s

"PRIM 1, SEC 1 = DC ESS. PRIM 2, SEC 2 = DC EHA. PRIM 3, SEC 3 = DC BUS 1"

45. What are the PRIM and SEC power supplies

Lower third of PFD

46. Where is Flap indication

All ailerons and spoilers 3-8

47. Which surfaces will operate in roll control (no failures)

CAM device prevents free play in control of rudder surface to increase pax comfort

48. What is the CAM device and where is it fitted

",EHA has elec motor which controls direction and rate of surface

49. "An EHA will have no servo valve, what carries out the function

To prevent force fight if both actuators are in an active mode (dual active mode)

50. Why do elevator EHAs have delta P sensors

"4 modes, Active (ops in relation to flight cont comps demands). Retracted (retracts to zero if rate command failure occurs). Blocking (prevents extension). Maintenance (device used to move surface manually)"

51. What are the modes of spoiler conventional actuator

"A unique maintenance key is used, when in maint (m) position key cannot be removed (key must be in ops (o) posn to remove)"

52. What is the spoiler maintenance device and how is it used

5 modes. As per conventional but have HYD active and ELEC active

53. What modes of operation do spoiler EBHAs have

"X4 total, slats 1, slats 2, flaps 1, flaps 2"

54. What Reset breakers are there for slats and flaps

CDS receives data via FCDC and directly from the PRIMs

55. How can CDS receive data from the PRIMs

","Electrical backup system activates, it is energised by green and yellow hydraulics"

56. "If all prims and secs are selected off, what happens

"DAMPED, as conventional actuator is driving the surface, it becomes ACTIVE if conventional fails"

57. In normal operation what mode is an EHA in

",Auxiliary functions of the ailerons

58. "What is LAF, speedbrake and droop and lift dumping

Short term pitch control

59. What are elevators used for


60. What modes can the elevators work in


61. In normal operations what modes run for the rudder sections

Electrically active

62. If spoiler 5 fails hydraulically what mode does it fail to

Retracted mode

63. If rate command fails to a spoiler what mode does it go to

"16 collars and 16 keys, if a key is used the spoiler goes to maintenance mode"

64. How many keys and collars required for the spoilers


65. In normal operation the yellow THS actuator is in what mode

",No as the POB fails on

66. "If there’s no electrical power to the THS, can it move electrically

The F/O’s pedals bellcranks

67. Where does the pedal feel and trim unit connect into


68. If you pull the speedbrake lever up what mode is it in

In manual flight only as they are inhibited when autopilot is on

69. the pitch trim switches can be used when

It resets the prims/secs but does not isolate them electrically

70. Selecting the prim/sec switches off does what


71. What is used normally for inner loop computation feedback

It is when 1 of aileron/elevators/rudder control surfaces is in hydraulically active mode and the unit in damping mode fails to hydraulically active mode as well. This is sensed by a delta p transducer

72. What is Force fight

Outer loop computation

73. Aircraft movement is a response in which loop

With a cockpit safety device/pin through the side of the sidestick

74. How do you lock the sidesticks

No as they will contact on the inboard side

75. If the slats are extended can you open the T/R’s

On the ground with IRS speed <30 Kts and related hydraulic pressure active or via an OMS test

76. When is the filling solenoid valve on an EHA activated

ACMS Real Time Monitoring

77. Rigging of an elevator is achieved using what

Only when the stab is commanded electrically will the POB be commanded to release

78. When is the THS Electrical power off brake released

By pack A and pack B resolver position sensors together

79. How is the stab monitored

PRIMs and backup electrical system

80. What do the pitch trim switches feed

"Flaps - Green & Yellow Hyds together, Slats - Green hyds & Electrical motor together"

81. What source of energy is used to move the flaps and slats

On the bottom of the PFD LHS

82. Where are the flap/slat indications normally

FPPU - flap position pickup unit

83. On the flap pcu what is the position sensor called

APPU - Asymmetric position pickup unit

84. Apart from the FPPU what is the other type of flap/slat position sensor

"2 on each unit but slats is a power off brake and a pressure off brake, flaps use 2 pressure off brakes"

85. How many POB’s on the WTB’s

"4, 1 between each section of flap"

86. How many interconnecting struts are there

",Opposite SFCC flap section will take over command

87. "If a SFCC unit flap section fails, what happens

"A valid detent position, A out-of-detent position, A invalid lever position"

88. What does the SFCC monitor the flap lever for

Flap auto command is actioned for safety reasons only

89. Why are the flaps automatically commanded to move

Normally SFCC1 sends commands to the Motor Control Electronics for movement of the motor. If it fails then SFCC2 will takeover as per dual control concept

90. The slat pcu electrical motor is controlled by what

Only via an OMS function can control of the eMotor be regained

91. If the hydraulics are not available to the slat pcu which would cause the eMotor to shutdown. On the ground how could you then move the slats

The wtb’s have be manually released at each wtb before driving the flap shaft manually

92. How do you manually drive the flaps or slats

",The torque limiter will popout a mechanical indicator and the flap asymmetry will cause a flap shutdown. To reset the torque limiter it has to be driven in the reverse of the direction that caused the failure

93. "A torque limiter detects overtorque, how do you know and how is it reset