When is the TAC (Thrust Asymmetry Compensator) available?

Unavailable-

Below 70 knots on the ground

When reverse thrust is applied

System malfunction,

Loss of engine thrust data

Only available when flight controls are in the NORMAL mode

Automatically disengages-

When engine thrust data is lost

Engine severe damage

Engine surges if unable to determine an accurate thrust level

Manually overridden-

By making manual rudder inputs

(FCOM  Vol 2 Rev 2- 9.20.15)

Normal

(FCOM Vol 2, Rev 2- 9.10.1)

When the PFCs can no longer support the Normal mode due to internal faults or lack of required information from other airplane systems they automatically revert to the secondary mode.

(FCOM Vol 2, Rev 2- 9.20.7)

When the PFC's can no longer support the normal mode due to-internal faults or lack of required information from other airplane systems [airspeed and/or inertial reference data] they automatically revert to the secondary mode.

(Reference needed for bracketed items)

(FCOM Vol 2 Rev 2- 9.20.7)

All flight controls still function normally. The elevator and rudder may be more sensitive at some airspeeds. The following features and protections are lost

1. Gust Suppression

2. Autopilot

3. Auto Speed Brake

4. Tail Strike Protection

5. Envelope Protection (bank angle, overspeed, ,stall,  )

6. Wheel to rudder cross-tie

7. Thrust Asymmetry Compensation

8. Yaw Dampening (may be degraded or inoperative)

Hints-

[Normal mode is the GATEWAY to an uneventful flight]

[If you loose envelope protection you have to fly like a BOS]

(FCOM Vol 2 Rev 2- 9.20.7 & 16)

FLIGHT CONTROL MODE (Amber/Caution)

(FCOM Vol 2, Rev 2- 9.20.7)

Normally with dual pitch trim switches on each control wheel.

(FCOM Vol 2, Rev 2- 9.20.10)

No

(FCOM ??? Vol 2)

No, they are inhibited.

(FCOM Vol 2, Rev 2- 9.20.10)

On the ground-The pilot is able to directly control the stabilizer position using the pitch trim switches In Flight-The pitch trim switches do not position the stabilizer directly, but make inputs to the PFCs to change the trim reference speed. When trim inputs are made, the PFCs automatically move the elevators to achieve trim change and then move the stabilizer to streamline the elevator.

(FCOM Vol 2, Rev 2- 9.20.10)

The speed at which the airplane will eventually stabilize if there are no control column inputs.

(FCOM Vol 2, Rev 2- 9.20.10)

They send trim speed commands to the PFCs in NORMAL MODE, and move the stabilizer in all modes. They have priority over control wheel pitch trim commands in ALL FLIGHT MODES.

(FCOM Vol 2, Rev 2- 9.20.11)

No,

however they DO move the stabilizer.

*Note- The alternate pitch trim levers should NOT be used with the autopilot engaged, or during stall/overspeed protection.

(FCOM Vol 2, Rev 2- 9.20.11)

It controls the initial effects of an engine failure with control wheel inputs only

(FCOM Vol 2, Rev 2- 9.20.16)

Control wheel inputs can deflect the rudder up to 8 degrees [full thrust engine loss requires about 12 degrees of rudder trim].

(FCOM Vol 2, Rev 2- 9.20.16)

(reference needed for bracketed item)

These conditions met:

In flight below 210 knots airspeed

In NORMAL mode

(FCOM Vol 2, Rev 2-.9.20.16)

No

(FCOM Vol 2, Rev 2- 9.20.7)

Yes by moving the PRIMARY FLIGHT COMPUTERS switch to DISC.

(FCOM Vol 2, Rev 2- 9.20.9)

All Flight control surfaces remain operable.

The elevator and rudder are more sensitive at some airspeeds. 

No TAC for Thrust asymmetry protection.

No Pitch stabilization to correct for flap and thrust changes

(FCOM Vol 2, Rev 2- 9.20.7 & 9)

No

(FCOM Vol 2, Rev 2- 9.20.7 & 9)

Secondary Mode- Autopilot Auto speed brake envelope protection gust suppression tail strike protection thrust asymmetry compensation wheel to rudder cross-tie yaw dampening (may be degraded or inoperative) additionally in Direct Mode- manual rudder trim cancel switch yaw dampening

(FCOM Vol 2, Rev 2- 9.20.7, 9 & 16)

What is Bank Angle Protection?

Autopilot returns bank angle to 30 degrees if the airplane reaches 35 degrees. This feature is disarmed when the Autopilot Disengage Bar is down (disengaged).

(FCOM Vol 2, Rev 2- 9.20.14)

Describe Overspeed Protection.

Overspeed protection limits the speed to which the airplane can be trimmed.  At VMO/MMO, overspeed protection limits the trim reference speed so that trim is inhibited in the nose down direction. The pilot must apply continuous forward column force to maintain airspeed above VMO/MMO. Use of the alternate pitch trim levers does not reduce column forces.

(FCOM Vol 2, Rev 2- 9.20.11)

Describe Stall Protection

Stall protection limits the speed to which the airplane can be trimmed. The trim reference speed is limited by inhibiting trim in the nose up direction when the airplane slows to a speed where maneuver margin is limited.  The pilot must apply continuous aft column pressure, at higher than normal force, to maintain airspeed below trim inhibit speed.

(FCOM Vol 2, Rev 2- 9.20.11)

Name the two system electronic components in the flight control system.

3 PFCs (Primary Flight Computers)

4 ACEs (Actuator Control Electronics)

(FCOM Vol2, Rev 2- 9.20.1)

What flight controls do you have with the loss of all four ACES?

Mechanical backup control of-

2 select spoiler panels number 4 and 11

Alternate pitch trim

*Note- only intended for level flight while ACEs reboot

(FCOM ??? Vol 2)

Flap and slat electronic units are inoperative Flaps and slats will have to be extended in alternate mode, which takes significantly longer time.

(FCOM ??? Vol 2,)

How do the Slats operate in Alternate Mode?

Flaps and slats extend simultaneously

Slats retract after flaps are up

Slats are limited to midrange

*Asymmetry protection, uncommanded motion protection, autoslats, Flap/slat load relief are Not available

(FCOM Vol 2, Rev 2- 9.20.20)

What is the maximum flap setting in the alternate mode?

20°

(FCOM Vol 2, Rev 2-  9.20.20)

What do the slats do in the secondary mode?

When are flaps/slats inhibited on the ground in the secondary mode?

If they are up when the system goes to secondary

Slats fully extend as soon as flaps are selected

If they are at mid position when the system goes to secondary-Slats remain at mid position until flaps are retracted to UP, or extended beyond 20°

If in the air, and Above 256 kts-

Slats will retract to midrange or will not extend past midrange If on the ground-

electric motor use is inhibited

Below 40 kts

Center hydraulic pressure is low

Two of the following-

Left N2 below 50%

Right N2 below 50%

Primary external power available

(FCOM Vol 2, Rev 2- 9.20.19)

When do the slats normally go from mid range to fully extended?

When flaps are selected to 25°

(FCOM Vol 2, Rev 2- 9.20.18)

Slats go down first, and come up last.

Flaps UP- Slats are up

Flaps 1, 5, 15, and 20- Slats are midrange

Flaps 25 and 30- Slats are fully extended

(FCOM Vol 2, Rev 2- 9.20.18-19)

Disables bank angle protection.

(FCOM Vol 2, Rev 2- 9.20.14)

When does TAC add rudder to minimize yaw?

If the thrust level on one engine differs by 10 percent or more from the other engine

(FCOM ???  Vol 2)

Why does the pilot control system provide feedback to the controls?

Since the system is fly by wire, the [back drive actuators] are the only source of feedback to provide conventional feel and pitch responses.

(FCOM Vol 2, Rev 2- 9.20.1)

(reference for bracketed item needed)