C-40 FLIGHT CONTROLS

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    What does #1 do in STBY RUD, OFF, and ON?
    STBY RUD - activates standby hydraulic system pump and opens standby rudder shutoff valve to pressurize standby rudder power control unit.

    OFF - closes flight control shutoff valve isolating ailerons, elevators and rudder from associated hydraulic system pressure.

    ON (guarded position) - normal operating position.
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    What does #2 indicate?
    Illuminated (amber) -

    -indicates low hydraulic system (A or B) pressure to ailerons, elevator and rudder

    -deactivated when associated FLIGHT CONTROL switch is positioned to STBY RUD and standby rudder shutoff valve opens.
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    When is #2 deactivated?
    -deactivated when associated FLIGHT CONTROL switch is positioned to STBY RUD and standby rudder shutoff valve opens.
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    What does #3 do in ON and OFF?
    ON (guarded position) – normal operating position.

    OFF – closes the respective flight spoiler shutoff valve.

    Note: Used for maintenance purposes only.
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    When does #4 indicate?
    Illuminated (amber) – yaw damper is not engaged.
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    What does #5 do in OFF and ON?
    OFF – disengages yaw damper.

    ON –

    -engages main yaw damper to main rudder power control unit if the B FLT CONTROL switch is in the ON position

    -engages standby yaw damper to standby rudder power control unit if both the A and B FLT CONTROL switches are in the STBY RUD position.
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    What does #6 STANDBY HYDRAULIC LOW QUANTITY Light indicate?
    Illuminated (amber) -

    -indicates low quantity in standby hydraulic reservoir

    -always armed.
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    What does #6 STANDBY HYDRAULIC LOW PRESSURE Light indicate?
    Illuminated (amber) -

    -indicates output pressure of standby pump is low

    -armed only when standby pump operation has been selected or automatic standby function is activated.
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    What does #6 STBY RUD ON Light indicate?
    -Illuminated (amber) - indicates the standby rudder system is commanded on to pressurize the standby rudder power control unit.
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    What does #7 do in OFF and ARM?
    OFF (guarded position) – normal operating position.

    ARM – closes TE flap bypass valve, activates standby pump, and arms the ALTERNATE FLAPS position switch.
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    What does #9 indicate?
    Armed when the TE flaps are up or down.

    Illuminated (amber) -

    -indicates excessive differential pressure in the elevator feel computer.

    -could be a problem with the elevator feel pitot tube
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    What does #10 indicate?
    Illuminated (amber) –

    -indicates failure of the speed trim system

    -indicates failure of a single FCC channel when MASTER CAUTION light recall is activated and light extinguishes when Master Caution System is reset.
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    What does #11 indicate?
    Illuminated (amber) –

    -indicates failure of the mach trim system

    -indicates failure of a single FCC channel when MASTER CAUTION light recall is activated and light extinguishes when master caution system is reset.
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    What does #12 indicate?
    Illuminated (amber) –

    -indicates failure of the auto slat system

    -indicates failure of a single Stall Management/Yaw Damper (SMYD) computer when illuminated during MASTER CAUTION recall and extinguishes when master caution system is reset.
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    What does #1 do?
    -provides for manual operation of stabilizer

    -overrides any other stabilizer trim inputs

    -rotates when stabilizer is in motion.

    Note: Handle should be folded inside stabilizer trim wheel for normal operation
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    What does #3 indicate?
    Corresponds to allowable range of trim settings for takeoff.
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    What does #5 do in NORMAL and CUTOUT?
    NORMAL – normal operating position.

    CUTOUT – deactivates stabilizer trim switch operation.
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    What does #6 do in NORMAL and CUTOUT?
    NORMAL – normal operating position.

    CUTOUT –

    -deactivates autopilot stabilizer trim operation

    -autopilot disengages if engaged.
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    What does #7 do in OVERRIDE and NORM?
    OVERRIDE – bypasses the control column actuated stabilizer trim cutout switches to restore power to the Stabilizer Trim Switches

    NORM (guarded position) – normal operating position.
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    What does #8 indicate?
    Operates only with autopilot engaged. Remains extinguished with autopilot not engaged.

    Illuminated (amber) – autopilot not trimming stabilizer properly.
  21. What does the speed trim system do?
    The purpose of the STS is to return the airplane to a trimmed speed by commanding the stabilizer in a direction opposite the speed change. The STS monitors inputs of stabilizer position, thrust lever position, airspeed and vertical speed and then trims the stabilizer using the autopilot stabilizer trim. As the airplane speed increases or decreases from the trimmed speed, the stabilizer is commanded in the direction to return the airplane to the trimmed speed.

    STS operates most frequently during takeoffs, climb and go-arounds. Conditions for speed trim operation are listed below:

    -STS Mach gain is fully enabled between 100 KIAS and Mach 0.60 with a fadeout to zero by Mach 0.68

    -10 seconds after takeoff

    -5 seconds following release of trim switches

    -Autopilot not engaged

    -Sensing of trim requirement
  22. What does the Elevator Feel Shift Module (EFS) do?
    Works with the yaw damper and speed trim to help the pilot identify and prevent further movement into a stall condition.  The EFS module increases hydraulic system A pressure to the elevator feel and centering unit during a stall. This approximately doubles control column forces.  There are no flight deck indications that the system is properly armed or activated.
  23. How many ailerons are there?
    2

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  24. How do the ailerons operate normally?
    The Captain’s control wheel is connected by cables to the aileron Power Control Units (PCUs) through the aileron feel and centering unit. The First Officer’s control wheel is connected by cables to the spoiler PCUs through the spoiler mixer. The two control wheels are connected by a cable drive system which allows actuation of both ailerons and spoilers by either control wheel.
  25. How are the ailerons operated with a loss of hydraulic system A or B?  How are they operated with a loss of system A and B?
    A or B:  Operate normally.

    A and B:  Manual reversion.  With total hydraulic power failure the ailerons can be mechanically positioned by rotating the pilots' control wheels. Control forces are higher due to friction and aerodynamic loads.
  26. What happens if the spoilers or ailerons become jammed?
    If the ailerons or spoilers are jammed, force applied to the Captain’s and the First Officer’s control wheels will identify which system, ailerons or spoilers, is usable and which control wheel, Captain’s or First Officer’s, can provide roll control. If the aileron control system is jammed, force applied to the First Officer’s control wheel provides roll control from the spoilers. The ailerons and the Captain’s control wheel are inoperative. If the spoiler system is jammed, force applied to the Captain’s control wheel provides roll control from the ailerons. The spoilers and the First Officer’s control wheel are inoperative.
  27. How are the ailerons trimmed?
    Dual AILERON trim switches, located on the aft electronic panel, must be pushed simultaneously to command trim changes. The trim electrically repositions the aileron feel and centering unit, which causes the control wheel to rotate and redefines the aileron neutral position.
  28. Is aileron trim allowed with the autopilot engaged?
    No.  If aileron trim is used with the autopilot engaged, the trim is not reflected in the control wheel position. The autopilot overpowers the trim and holds the control wheel where it is required for heading/track control. Any aileron trim applied when the autopilot is engaged can result in an out of trim condition and an abrupt rolling movement when the autopilot is disengaged.
  29. Is aileron trim available during manual reversion?
    Yes, because aileron trim is electrically driven.
  30. When do the flight spoilers operate to aid in roll control?
    When the control wheel is displaced more than approximately 10°, spoiler deflection is initiated.
  31. How many spoiler panels are used as flight spoilers?  What other function do the flight spoilers provide?
    8

    Speed brakes

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  32. How many elevators are there?
    2

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  33. How are the elevators operated normally?
    Cables connect the pilots’ control columns to elevator Power Control Units (PCUs) which are powered by hydraulic system A and B. The elevators are interconnected by a torque tube.
  34. How are the elevators operated with a loss of hydraulic system A or B?  How are they operated with a loss of system A and B?
    A or B:  Operate normally.

    A and B:  Manual reversion.  Manual stabilizer control is accomplished through cables which allow the pilot to position the stabilizer by rotating the stabilizer trim wheels. The stabilizer is held in position by two independent brake systems.
  35. What happens in the event of a control column jam/elevator jam?
    In the event of a control column jam, an override mechanism allows the control columns to be physically separated. Applying force against the jam will breakout either the Captain’s or First Officer’s control column. Whichever column moves freely after the breakout can provide adequate elevator control.  Although total available elevator travel is significantly reduced, there is sufficient elevator travel available for landing flare. Column forces are higher and exceed those experienced during manual reversion.
  36. What system is available to assist with a jammed elevator?
    Stab trim
  37. What does the elevator feel system do?
    The elevator feel computer provides simulated aerodynamic forces using airspeed (from the elevator pitot system) and stabilizer position. Feel is transmitted to the control columns by the elevator feel and centering unit.
  38. What does the Mach trim system do, and when does it operate?
    A Mach trim system provides speed stability at the higher Mach numbers. Mach trim is automatically accomplished above Mach .615 by adjusting the elevators with respect to the stabilizer as speed increases.
  39. How many speeds does the stabilizer trim motor have, and when do they operate?
    The main electric and autopilot stabilizer trim have two speed modes: high speed with flaps extended and low speed with flaps retracted.
  40. How is the rudder operated normally?
    Each set of rudder pedals is mechanically connected by cables to the input levers of the main and standby rudder PCUs.  The main PCU consists of two independent input rods, two individual control valves, and two separate actuators; one for Hydraulic system A and one for Hydraulic system B. The standby rudder PCU is controlled by a separate input rod and control valve and powered by the standby hydraulic system. All three input rods have individual jam override mechanisms that allows input commands to continue to be transferred to the remaining free input rods if an input rod or downstream hardware is hindered or jammed.
  41. How is the rudder operated with a loss of hydraulic system A or B or A and B?
    Loss of A:  system B and the standby rudder PCU

    Loss of B:  system A and the standby rudder PCU

    Loss of A and B:  standby rudder PCU
  42. At speeds above approximately ____, both hydraulic system A and B pressure are each reduced within the main PCU by approximately ____ each. This function limits full rudder authority in flight after takeoff and before landing.
    135 kts

    25%
  43. What does the main rudder PCU Force Fight Monitor (FFM) do?
    The main rudder PCU contains a Force Fight Monitor (FFM) that detects opposing pressure (force fight) between A and B actuators. This may occur if either system A or B input is jammed or disconnected.
  44. What happens when the Force Fight Monitor (FFM) detects opposing pressure?
    The FFM does the following automatically:   

    -turns the standby hydraulic pump on

    -opens the standby rudder shutoff valve to pressurize the standby rudder PCU

    -illuminates the STBY RUD ON, Master Caution, and Flight Control (FLT CONT) lights.
  45. How does rudder trim operate and does it displace the rudder pedals?
    The FFM output is used to automatically turn on the Standby Hydraulic pump, open the standby rudder shutoff valve to pressurize the standby rudder PCU, and illuminate the STBY RUD ON, Master Caution, and Flight Control (FLT CONT) lights.
  46. Which hydraulic system normally powers the yaw damper?
    During normal operation the main yaw damper uses hydraulic system B and the SMYD computers provide continuous system monitoring.
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    What would cause #4 to illuminate?
    The YAW DAMPER Switch automatically moves to OFF, the amber YAW DAMPER light illuminates and the YAW DAMPER switch cannot be reset to ON when any of the following conditions occur:

    -SMYD senses a yaw damper system fault,

    -SMYD senses that the yaw damper does not respond to a command,

    -B FLT CONTROL switch is positioned to OFF or STBY RUD.
  48. If the yaw damper disengages automatically, when can it be re-engaged?
    During manual reversion flight (loss of hydraulic system A and B pressure), both FLT CONTROL switches are positioned to STBY RUD. In this case, the YAW DAMPER switch can be reset to ON and the standby hydraulic system powers the standby yaw damper.
Author
CForty
ID
350344
Card Set
C-40 FLIGHT CONTROLS
Description
C-40 FLIGHT CONTROLS
Updated