FLT CONTROL PANEL

Question 1

FLT CONTROL ‘A’ & FLT CONTROL ‘B’

• 3 position -

STBY RUD

OFF

A ON

Answer 1

[1sp answer: -

• there is no ‘manual reversion’ for rudder
• STBY RUD:
  
  • ​activates standby hyd pump
  • opens standby rudder shutoff valve (which pressurizes the standby rudder PCU)
    
    • this function is what turns on the STBY RUD ON (amber) light
  • Flt Control ‘LOW PRESS’ light turns off
    
    • indicates the standby rudder SOV has opened
  • For ‘B’ System Only:
    
    • will cause yaw damper switch to MAGNETICALLY release to OFF
    • this causes the YAW DAMPER light to illuminate
• OFF:
  
  • closes flt control shutoff valve (this isolates the ailerons, elevators and rudder from hyd system)
  • yaw damper switch flips to OFF (magnetically) when SYS B is placed through OFF position
  • respective LOW PRESSURE (amber) light AND FEEL DIFF PRESS light illuminate

​

• ON:
  
  • ​normal operating position
  • opens flt control SOV to ailerons, elevators, elevator feel and rudder from assoc hyd system
• ** NOTE: for the Standby Yaw Damper switch to operate at least one FLT CONTROL switch A or B must be in STBY RUD and the other has to be in either OFF or STBY RUD

Question 2

FLT CONTROL ‘LOW PRESSURE’ LIGHTS

Answer 2

[1sp - low pressure in (hyd sys a (or b). How will the QRH guide us to fix this problem? - lift the guard and move switch to standby rudder position - which closes the hydraulic shutoff valve to the A (or B) system then the low pressure light will normally go out, the standby rudder light will come on - the standby rudder low pressure light will be armed) - SOAP and SOAPY

S - standby pump on

O - open SRSOV

A - Arm Low pressure light

P - position indicating (verify by low press lt out) which tells us that the SRSOV has opened successfully

Y - yaw damper not available (B only)]

• Illuminated (AMBER):
  
  • indicates low pressure to aileron, elevator, elevator feel computer and rudder (< 1300 psi)
  • this light is DEACTIVATED when associated FLT CONTROL SWITCH is set to STBY RUD and the standby rudder SOV OPENS.
    
    • the light going out VERIFIES the SOV is OPEN
• when the FLT CONTROL is in ON or OFF the standby rudder SOV is CLOSED (so this light works normally)

Question 3

FLIGHT SPOILERS SWITCHES

• 2 positions -

ON

OFF

Answer 3

• for MAINT PURPOSES ONLY
• ON:
  
  • normal operating position
• OFF:
  
  • closes respective FLIGHT SPOILER SOV
  • ‘A’ Spoilers: 2, 4, 9, 11
  • ‘B’ Spoilers: 3, 5, 8, 10
  • Note: Ground spoilers are NOT affected by this switch they are ‘FLIGHT’ spoiler switches

Question 4

YAW DAMPER Light

Answer 4

• Illuminated (amber) - Yaw damper is NOT engaged or is inop.
• Note: losing ‘B’ hydraulic pressure does NOT cause this light to go ON but the yaw damper is inop

Question 5

YAW DAMPER Switch

• 2 positions -

OFF

ON

Answer 5

• OFF:
  
  • disengages the yaw damper (turns ON - YAW DAMPER light)
  • Switches OFF if:
    
    • ‘B’ FLT CONTROL Switch moved TO or THROUGH the OFF position
    • power interruption to the #1 AC transfer bus
    • yaw damper rate gyro or actuator fails
  • Switch AUTOMATICALLY moves to the OFF position - YAW DAMPER light illuminates - and the YAW DAMPER Switch CANNOT be RESET: (any of the following)
    
    • ‘B’ FLT CONTROL switch is moved to OFF or STBY RUD
    • SMYD senses a yaw damper SYSTEM FAULT or YAW DAMPER doesnt respond to a command
• ON:
  
  • connects MAIN YAW DAMPER to MAIN RUDDER PCU (if ‘B’ switch - ON)
  • connects STANDBY YAW DAMPER to STANDBY RUDDER PCU ( if both ‘A’ and ‘B’ switch in STBY)
• NOTE: solenoid WILL NOT LATCH if rate gyro is not online (IRUs aligning) and there is no compass on the ND

Question 6

LOW QUANTITY Light (Stby Hyd)

Answer 6

• Illuminated (Amber):
  
  • indicates Low Quantity in Standby Hyd reservoir (50%)
  • always armed
• a leak in the standby system will empty the standby reservoir and take ‘B’ down to approx 72%

Question 7

LOW PRESSURE Light (Standby Hyd)

Answer 7

• Illuminated (Amber)
  
  • standby pump output pressure is low (electric motor driven pump) (< 1300 psi)
• ARMED: (any of the following)
  
  • either FLT CONTROL switch to STBY RUD
  • ALTERNATE FLAPS arm switch to ARM
  • Automatically:
    
    • FLT CONTROL A or B - ON (normal) AND
      
      • complete loss of A OR B - AND
      • On ground (> 60 kts) or In flight (with flaps extended)
    • FFM Trips (force fight monitor)

Question 8

STBY RUD ON Light

Answer 8

• Illuminated (Amber):
  
  • indicates STANDBY RUDDER system is activated (ie Standby Rudder PCU is Pressurized)
  • does not function with ALT FLAPS master switch activation
  • activates MC and FLT CONT caution
• Standby Rudder system turned on when:
  
  • either FLT CONTROL switch to STBY RUD
  • Automatically: (either of the 2 below)
    
    • ​Takeoff or Landing AND
      
      • FLT CONTROL Switch A or B - ON (normal) and a complete loss of A OR B - AND
      • On ground (> 60 kts) or In flight (with flaps extended)
    • FFM Trips (force fight monitor)
• When airborne and Flaps are retracted the Standby Pump shuts off
• if this light goes ON WITHOUT crew action or hyd system malf, either:
  
  • FFM inadverterntly activated the Standby Pump (and powering the standby PCU - 3 PCUs powering rudder vs 2)
  • or there is a pressure difference between the 2 main PCU (indicates a Jammed Condition)

Question 9

ALTERNATE FLAPS MASTER SWITCH

• 2 position -

OFF

ARM

Answer 9

[1sp - what happens when we put switch to arm?

1. Arm the UP/DN switch

2. Activate the standby pump

3. Close trailing edge flap bypass valve (locks out hyd fluid) ]

• OFF:
  
  • (guarded) - normal operating position
  • turns OFF standby pump if on and closes LE standby SOV
• ARM: (3 things)
  
  • closes TE flap bypass valve
  • activates standby pump (arms LOW PRESS light)
  • arms ALTERNATE FLAPS position switch (electrical switch)
• During ALTERNATE FLAPS OPERATION:
  
  • no flap load relief
  • no TE Flap asymmetry and skew protection
  • no UCM detection

Question 10

ALTERNATE FLAPS Position Switch

• 3 position -

UP

OFF

DOWN

Answer 10

[1sp - what is main purpose of the Alt Flaps switch?

- in case we lose hyd system B so we can bring up and down electrically the trailing edge flaps

* note trailing edge devices are extended with an electric motor and may be retracted - the LEDs are extended using standby hydraulic pressure and may NOT be retracted]

• functions ONLY when Alt Flaps Master sw in ARM
• only FULL EXTEND lines in standby system (no retract lines)
• this controls an ELECTRIC motor that extends or retracts TE FLAPS
• must be held down
• no assymmetry or skew protection

UP:

• electrically retracts TE Flaps (LEDs remain extended - cannot be retracted by ALT system)
• NOT spring loaded to OFF (ie can position to UP and leave it)

OFF:

• Normal operating position
• Stops movement of TE Flaps

DOWN: (spring loaded)

• (momentarily) fully extends LEDs using Standby pressure
• (hold) electrically extends TE flaps until released

Note:

• takes approx 30 sec for LE Flaps to deploy and 1 min for the SLATS to deploy

Question 11

FEEL DIFF PRESS Light

Answer 11

[1sp - if this light comes on - what does that mean? it means excessive differential pressure in the elevator feel computer]

• • Illuminated (Amber):
    
    • indicates excessive differential pressure in the ELEVATOR FEEL COMPUTER
      
      • could be caused by erroneous activation of the Elevator Feel Shift Module
      • or loss of SYS A or B
      • Elevator Pitot system blocked or failed

​

• the Feel Diff Press light monitors both A & B metered pressures and closes if there is greater than 25% difference in pressure

Question 12

SPEED TRIM FAIL Light

1sp - what happens if we are flying and the speed trim fail light comes on? What does that mean - what can cause that?

What if we are in descent - push recall and the SPEED TRIM FAIL light illuminates?

Answer 12

[1sp -(a) it means that BOTH channels of the FCC computers failed. If its a failure of only 1 computer - it will be on recall.

(b) that means only one channel from the FCC computer has failed.

* same answer as mach trim fail ]

• there is a speed trim channel in each FCC (A & B)
• FCC COMPUTER
• DUAL CHANNEL LIGHT

Illuminated (Amber):

• indicates failure of the speed trim system
• goes out when MC system is reset (if single channel fail) ie. this light will go out

Question 13

MACH TRIM FAIL Light

1sp - what happens if we are flying and the mach trim fail light comes on? What does that mean - what can cause that?

What if we are in descent - push recall and the mach TRIM FAIL light illuminates?

Answer 13

[1sp -(a) it means that BOTH channels of the FCC computers failed. If its a failure of only 1 computer - it will be on recall.

(b) that means only one channel from the FCC computer has failed.

* same answer as speed trim fail ]

• • FCC COMPUTER
• DUAL CHANNEL

Illuminates (Amber):

• indicates failure of the MACH TRIM system
• during single channel failure (on recall) this light will go out if MC pressed.

Question 14

AUTO SLAT FAIL Light

1sp - what happens if we are flying and the auto slat fail light comes on? What does that mean - what can cause that?

What if we are in descent - push recall and the auto slat light illuminates?

Answer 14

[1sp - it means that both channels from the SMYD computer have failed. 1 channel will come up on recall]

• SMYD Computers
• DUAL CHANNEL LIGHT

Illuminates (Amber):

• indicates a failure of the auto slat system
• indicates a failure of a single SMYD computer (during recall)
• light extinguishes (if MC reset with single channel failure)
• if one SMYD auto slat function is not available - the other SMYD can still operate autoslats
• both SMYD failures also illuminate the MC and FLT CONT lights