Aircraft Flight Control System Cruise Sub-mode Logic

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What is the maximum rate of stabilizer movement when a pitch trim switch is activated?

0.4 degrees per second

What conditions must be satisfied for the FCS to be in the Cruise sub-mode?

On-ground sub-mode logic not satisfied, AOA limiting sub-mode logic not satisfied, and Autopilot engaged OR both landing gear and flap handles up

How is pitch control designed at high altitudes?

Conventional with additional damping

What protection is provided if the aircraft exceeds the maximum operating speed?

Limiting column authority in the nose down direction Signup and view all the answers

Is there any protection against exceeding the maximum mach number?

No Signup and view all the answers

Describe the backup pitch control mode and how it is activated.

The backup pitch control mode is a secondary control mode that is entered when communication is lost between the Flight Control Computer (FCC) and the Horizontal Stabilizer Control Unit (HSCU). In this mode, both the pilot and copilot backup pitch switches must be actuated simultaneously in the same direction (nose up or nose down) to initiate pitch trim. Signup and view all the answers

What are the components that make up the pilot and copilot control wheel and column assemblies?

The key components of the pilot and copilot control wheel and column assemblies include the control wheel, column pushrods, pulley bracket assemblies, and the pilot and copilot control module assemblies. Signup and view all the answers

What is the purpose of the pitch override mechanism?

The purpose of the pitch override mechanism is to provide a means for the pilot or copilot to override the automatic pitch control system and manually adjust the pitch of the aircraft. Signup and view all the answers

Explain the concept of pitch authority limit and how it is implemented in the aircraft's pitch control system.

The pitch authority limit is a design feature that restricts the maximum pitch up or pitch down authority of the aircraft's pitch control system. This limit is implemented to prevent the pilot or autopilot from commanding excessive pitch inputs that could exceed the aircraft's structural limits or lead to an unsafe flight condition. Signup and view all the answers

Describe the purpose and operation of the pitch trim nose up and nose down limit switches.

The pitch trim nose up and nose down limit switches are designed to prevent the pitch trim system from commanding the horizontal stabilizer beyond its physical travel limits. When the stabilizer reaches the nose up or nose down limit, the corresponding limit switch is activated, which cuts off the trim command and prevents further movement in that direction. Signup and view all the answers

Describe the operation of the yaw damper system between 60 KCAS and 90 KCAS.

Between 60 KCAS and 90 KCAS, the yaw damper will smoothly transition from 0% to 100% effectiveness. The yaw damper will then be active using simple yaw rate feedback (from the IRS sensors) to the rudder in combination with the rudder pedal input. Signup and view all the answers

What is the maximum rate of stabilizer movement commanded by the pitch trim system?

Pitch trim actuation commands the stabilizer to move at its maximum rate of 0.4 degrees per second in the direction commanded. Signup and view all the answers

Describe the conditions that must be met for the FCS to be in the Takeoff and Landing (TL) sub-mode.

The FCS will be in the Takeoff and Landing (TL) sub-mode when Normal mode conditions are satisfied and the following conditions are all satisfied: The On-ground logic is not satisfied, AOA limiting logic is not satisfied, Autopilot is not engaged, and the landing gear handle is down or the flap handle is greater than 5°. Signup and view all the answers

How does the pitch control system behave at speeds of approximately 135 KCAS and below?

At speeds of approximately 135 KCAS and below, full column deflection will result in full elevator control, except for a small flap bias. Signup and view all the answers

Describe how the pitch control system's behavior changes as speed increases above approximately 135 KCAS.

As speed increases above approximately 135 KCAS, the amount of elevator deflection per column deflection will decrease so that the pitch response will not be too sensitive. Signup and view all the answers

What is the recommended approach speed in strong or gusty wind conditions?

VREF plus ½ of the steady state wind plus the full gust increment, not to exceed VREF + 20 KCAS. Signup and view all the answers

How does the roll control system work during the landing/flare phase?

Wheel deflection translates directly to aileron and roll spoiler deflection. Signup and view all the answers

What is the maximum deflection of the roll spoilers during landing/flare?

55 degrees Signup and view all the answers

What is the purpose of the yaw damper during landing/flare?

To damp dutch roll oscillations using sensor feedback to the rudder in combination with rudder pedal input. Signup and view all the answers

What is the effect of 'nose up trim' input during landing/flare?

Nose up trim has no effect. Signup and view all the answers