Flight controls Flashcards
What are the primary flight controls?
Aileron, elevator, and rudder.
What are the secondary flight controls?
Flaps, spoilers, horizontal stab and gust lock.
What do each of the Flight Control Electrical (FCE) systems control?
FCE 1 controls Pitch Trim Backup and Flaps
FCE 2 controls Normal Pitch Trim and Spoilers
What are the flap position degrees and airspeed limitations?
Flap 1 is 8 degrees, 180 kts
Flap 2 and 3 are each 26 degrees, 170 kts
What are the (3) functions of the spoilers?
1) Roll Spoiler – When flaps are at any position other than 0, and the control wheel is rotated more than 30 degrees left or right, the spoiler on the respective side deploys, providing increased roll authority.
2) Ground Spoiler – increases drag and dump lift on landing and rejected takeoff to reduce required stopping distance.
3) Speed Brake – increases drag and dump lift while in the air; only available with flaps retracted
What conditions must be met for ground spoilers to deploy?
1) aircraft on the ground
2) thrust levers idle
3) ground spoilers armed
(Ground spoilers deploy to 35 degrees at approximately 1.2 seconds)
Will the speed brakes function in conjunction with flaps?
No. The spoilers will not extend if flaps are beyond 0 degrees. If open, they will retract if flaps are commanded to extend.
What prevents the spoilers from opening further than their original position in the event of loss of hydraulic fluid?
A Hold-Down Lock Valve (HDLV). Its purpose is to trap hydraulic fluid in the retract chamber of the PCU in the event of hydraulic fluid loss. It shuttles to the by-pass position allowing the check valve to close and block fluid from exiting the retract chamber or the PCU, thereby preventing the control surface opening further than its original position.
If extended, at what airspeed will the speed brakes retract?
110kts
Will the speed brakes retract if the power is advanced?
Yes. If the speed brakes are deployed, or open, and you advance the power, they automatically retract. A CAS message confirms speed brake retraction. Placing the speed brake switch to up extinguishes the CAS message.
Describe the flaps.
Four-position, four-panel trailing edge Fowler Flaps mechanically actuated by jackscrews, which are powered by a DC electric motor. The Flight Control Electronics (EFC) operates one Power Drive Unit (PDU) which drives 6 flexible shafts, which operate the flap actuators.
What is the purpose of the Spring Loaded Rudder Booster system?
It provides force assistance to the pilot in case of thrust asymmetry by controlling the spring preload of two tension springs. When the rudder spring actuator is energized, the actuator is fully extended due to the external load from the tension springs. When the actuator solenoid valve is commanded by the FADECs during an asymmetric thrust operation, the actuator is in fully retracted position, which rotates the actuator bellcrank, forcing the tension springs to equally extend, and increasing their pre-loads. The tension springs supply a force on the spring fork, which transmits a hinge moment to the rudder torque tube through the connection rod and bellcrank.
The FADEC sends a signal to command the SLRB actuator when the thrust asymmetry between the engines is greater than 500 lbs and the airspeed is greater than 60 kts. The system will only be deactivated if at least one of these two conditions are met:
* asymmetry between the engines equal to or lower than 250lbs
* airspeed equal to or lower than 50kts
What besides the aircraft’s yaw damper provides yaw damping capability?
Ventral Rudder Surface.
(It is a small auxiliary rudder behind the tail-mounted ventral fin. It’s automatically activated via air data inputs once airspeed reaches 60 KIAS on the takeoff run and any time the primary yaw damper is OFF. With the yaw damper engaged, the ventral rudder locks in trail.
Inputs generated by the AFCS commands a dedicated autopilot servo, which transmits commands directly to the ventral rudder torque tube through steel control cables; it is not connected to the rudder control system, so has no interface with pilot command. The VRS lets you dispatch the airplane without a functioning yaw damper).
Which trims are commanded by the Trim Actuation System (TAS) through the trim panel?
Aileron and Rudder.
Describe the 3 second timer on the roll trim and rudder trim.
After 3 seconds of continuous trimming, the actuator will not move, so it is necessary to release the switch before commencing trimming.
This warning system mitigates spontaneous or commanded movement of the trim surface beyond safe limits.
