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Flight Control three operating modes
Normal mode
Secondary mode
Direct mode
To overcome a jam
apply force to the other column or wheel to overcome the jam
Actuator Control Electronics- four of them, they receive input signals from flight controls.  They send control signals to the primary flight control surfaces via different actuators.  No single ACE controls more than one actuator on a control surface.
Primary Flight Control- receive pilot input signals from ACE and send back control commands to the ACE.  These commands are received by ACE to position the flight control surfaces.
Information the PFC uses includes:
air data
inertial data
flap and slat position
engine thrust
radio altimiter
Pitch Control provided by:
two elevators
a moveable horizontal stabilizer
Roll Control provided by:
Two flaperons
Two Ailerons
Fourteen Spoilers
Yaw Control provided by:
Single Rudder
Partial Span Tab
Between the inboard and outboard flaps.  Provide Roll control in normal mode.  In high spd flight they (along with spoilers (except 5&10)) provide roll control, while the ailerons are locked out.
In Autopilot, the commands are sent directly to the ___.  Whereas, manual flight control inputs are sent to the ___.  In both cases, the signal from the PFC return to the ACE.
If the pilot manually overrides the autopilot the PFC is disconnected from the autopilot.
The PFC's self test (two minutes)
after the hydraulic systems are shut down, causing several EICAS alerts and status messages, trim indicator info blinks, and several failure indications display on the Synoptic.
Secondary Mode works by
sending pilot flight control inputs to the ACE and the PFC, where "simplified computaions" are sent back to ACE, where they are sent to the control surface actuators.
Secondary Mode degredations include:
TAC (Thrust Asymmetry)
Y aw Damping (degraded or inop)
E nvelope Protecetion
A utopilot
T ail Strike Protection
A uto speedbrakes
G ust Suppression
Direct mode engages when
when the ACE's detect a failure of all three PFC's or lose comms with them.

Manually selected

PFC's cut out entirely, only ACE's send signals directly to the flight control actuators.
Direct Mode additional losses over Secondary mode
Manual Rudder Trim cancel switch
No Yaw Damping
Mechanical backup
if there is a complete electrical shutdown, cables from the flight deck to selected spoilers and the stabilizer allow pilot to fly straight and level until electrical system restored.
Pitch contol by the pilot commands
the PFC's to generate a commanded maneuver, automatically positioning the stabilizer and elevator.  PFC's constantly monitor aircraft response to pilot input and respond accordingly.  Additionally, pitch changes to thrust changes, gear, flap, spoiler config changes, AOB up to 30, and turbulence are minimized by PFC's.
Primary pitch trim switches on the ground and in the air
Ground- pilot directly positions stabilizer

Air- Pilot inputs go to PFC's to change trim reference speed.  The PFC's automatically move the elevators to achieve the trim change, then move the stabilizer to streamline the elevator.
Stabilizer motion automatically occurs to streamline
the stabilizer and elevator for thrust and configuration changes.
Alternate pitch trim, controlled by the dual levers on the control stand, are linked
to the stabilizer trim control module (STCM) via control cables, and then mechanically to the stabilizer.  Alternate pitch trim has priority over the wheel pitch trim commands.
Use of Alternate pitch trim is not permitted
with autopilot engaged (it won't disconnect A/P)
during stall or overspeed protection (it moves the stab, but does not remove the column forces)
Stall protection is provided by
limiting the trim reference speed (min manuevering spd) so that trim is inhibited in the nose up direction.
Overspeed protection is provided by
limiting the trim reference speed (VMO/MMO) so that trim is inhibited in the nose down direction.
Airplane pitch control in Secondary and Direct mode takes control column inputs and commands
proportional elevator deflection instead of a manuever command.  No auto pitch compensation for:
thrust, gear, flap, speed brake config, changes, turbulence turns to 30 AOB
In secondary and direct mode elevator variable feel
provides two feel force levels (flaps up, down), instead of continuous variation with a/s.
In secondary and direct mode, what moves the stabilizer directly?
Both the primary pitch trim and alternate pitch trim.
Which spoilers are mechanically controlled?
4 & 11
Aileron trim
inhibited when autopilot engaged.
At ___ degrees roll, the bank angle protection kicks in and force rolls the control wheel back to ___.
The autopilot disengage bar disables
bank angle protection.
In Secondary and Direct mode roll control is
very similar to normal mode, except lose bank angle protection.
Rudder ratio changer
automatically reduces rudder deflection (for a given pedel input) as a/s increases.  In secondary and direct mode, limited to two fixed ratios (flaps up and down).
A differential of ___ between engine thrust level causes the TAC to automatically add rudder and minimize yaw.
10 percent (before liftoff does not fully compensate for failed engine so pilot can recognize, after liftoff it fully compensates)
TAC not available when
a/s less than 70kts on ground or when reverse thrust applied
(automatically disengaged due to loss of engine data)
Wheel to rudder Cross-Tie provides ability of control initial effects of an engine failure using control wheel inputs only.  How much can the control wheel deflect the rudder?
8 degrees (below 210 knots)
Primary source of power for the flight controls is the PMG's (two each) in the same housing as the
backup generators.  The PMG's give power to the PSA's (L feeds L) (R feeds C and R)
Should the PMG's fail,
the L and R transfer busses power the L,C1,C2,R TRU's.  
L TRU powers L Main DC, powers L PSA

R TRU powers R Main DC, powers R PSA

C1 TRU powers Capt Flt Inst, powers C PSA 
Should IDG's, and Backup Gens/PMG's all fail, resulting in a loss of both transfer busses
The RAT will deploy and power the C1 and C2 TRU (and center hydraulic power, if necessary- windmilling engine may be enough to run hydraulic pumps).    

The C1 TRU will power the Capt Flt Inst

The Capt Flt Inst bus powers the powers the C PSA

The Capt Flt Inst buss will also power the battery bus, which powers the Hot battery bus, which powers the L PSA.
If the RAT fails, the Main battery
Powers the hot battery bus which powers the L PSA.

The main battery also powers the C PSA, via the hot battery bus, battery bus and Capt flt inst.
If the Main Battery fails
the PSA's have individual batteries.  
x of y cards