Flight Controls

Question 1

What are the primary flight controls?

Answer 1

Rudder, Elevators, and spoiler assisted ailerons.

Question 2

Which controls are designated the Powered Flight Control Surfaces (PFCS) and why?

Answer 2

The Rudder, Elevators, and Spoilers are designated as the PFCS because the are hydraulically powered.

Question 3

Describe the Flight Control ECU.

Answer 3

• under the pax cabin floor
• two separate parallel channels (left and right)
• receive inputs from pilot commands and send electrical outputs to the flight controls, FDR, and the advisory and cautionary systems.
• each channel is powered by its respective left or right essential bus.

Question 4

Describe the elevators.

Answer 4

• mechanically controlled, hydraulically activated.
• separate, but tied together by a disconnect sys
• position is displayed on MFD
• three identical PCUs on each side, coincident to the #1, 2, and 3 HYD SYSs
• 2 PFTUs located in the upper vertical stab provide artificial feel according to inputs from the FCECU, ADU, and AHRS.
• 2 overload bungees protect the system, in case of a PCU jam.

Question 5

Describe the pitch trim system.

Answer 5

• two trim command switches are on the outboard horn of each yoke. Both must be activated to command a trim input.
• the FCECU uses inputs from the ADU and AHRS to determine trim rate as a function of airspeed and acceleration.
• trim is actuated by the PFTUs
• any command longer than three seconds will
  produce a clicking sound over the speakers and
  illuminate the ELEV TRIM SHUTOFF switch-lights.
• trim commands are prioritized by captain, copilot, and autopilot inputs.

Question 6

Describe the Flap Auto Pitch Trim System

Answer 6

• pitch trim is automatically commanded when flaps are moved between 15 and 35, and…
• the autopilot is not active, and
• airspeed is less than 200 KIAS, and
• there is no other pitch trim command.

Question 7

Elevator Asymmetry Caution Light

Answer 7

There is a position mismatch between the two elevators. Slow below 200.

Question 8

ELEV FEEL Caution Light

Answer 8

• indicates position disagreement between the PFTUs or the inability of the FCECU to control either.
• if one PFTU fails, the FCECU will hold it at its last valid position, and the other PFTU will operate normally.
• slow below 200.

Question 9

ELEV FEEL
RUD CTRL
SPLR OUTBD
&
PITCH TRIM
Caution Lights

Answer 9

These caution lights indicate a disagreement between ADUs or loss of valid AHRS acceleration inputs. Should be accompanied by an IAS MISMATCH message on the PFDs