Flight control laws - pitch

Ground mode is an aircraft control system that directly relates sidestick movement to elevator movement, without auto-trim.

Movement of the pilot's control stick on the ground.

The up-and-down movement of the aircraft's elevators.

Automatic adjustment of control surfaces.

Aircraft operation taking place on the ground.

The Trim Hydraulic System (THS) is initially set to 4° UP during ground operations. This setting remains within the green band on the indicator.

Before takeoff, the THS automatically adjusts to a specific value based on the aircraft's weight, center of gravity, and fuel distribution. This calculation is performed by the PRIM (Primary Flight Control Computer).

The pilot enters the Zero Fuel Weight Center of Gravity (ZFWCG) into the MCDU (Multi-Purpose Control Display Unit). This input is crucial for the THS takeoff setting calculation.

The automatic THS setting occurs only once before takeoff; the flight crew can manually change the setting if needed.

The proper THS setting ensures the aircraft maintains a stable attitude during takeoff, preventing unnecessary pitch changes or instability.

A flight mode that automatically controls the aircraft's load factor and ensures full flight envelope protection.

The pilot controls the aircraft's desired load factor by moving the sidestick. The aircraft automatically adjusts to maintain that load factor.

The system limits the aircraft's maneuvers to prevent exceeding its structural limits, keeping it within safe operating boundaries.

The pilot controls the elevator directly through the sidestick, but the aircraft still automatically adjusts for load factor and flight envelope protection.

When the sidestick is neutral and wings are level, the aircraft automatically maintains a 1 g load factor, correcting for pitch attitude.

The system automatically compensates for changes in speed and configuration, eliminating the need for the pilot to manually trim the aircraft.

Pilots only need to make minor corrections to the sidestick if the aircraft deviates from its intended flight path. The system handles the majority of the control.

If the pilot senses an overcontrol situation, they should release the sidestick to allow the system to regain control.

The aircraft maintains a 1 g load factor in pitch, meaning it stays balanced and level without the pilot needing constant input.

Autopilot controls the Trim Hydraulic System (THS) based on autopilot and load factor demands, adjusting pitch trim automatically to maintain the desired flight path.

Even with manual control, pitch trim is automatically adjusted to maintain stability and reduce pilot workload.

No pitch correction is needed during normal turns (up to 33° bank angle) once the turn is established. The aircraft automatically adjusts.

Automatic pitch trim is temporarily frozen in situations like manual trim commands, low altitude flare, low load factor, or high-speed protection.

When angle of attack protection is active, nose-up trim is limited to prevent exceeding safe limits. The nose can only trim up to 2° down from the initial entry setting.

Automatic pitch trim is frozen in these situations: manual trim commands, radio height below 100 ft for flaring, load factor lower than 0.5 g, or high-speed protection.

Automatic pitch trim is a system that automatically adjusts the aircraft's control surfaces (elevator) to maintain a stable attitude during flight.

During the flare, the aircraft is at low altitude and manually adjusting the trim is preferred for precise control. The auto trim freezes to avoid unwanted adjustments.

Load factor is a measure of the force acting on the aircraft. 1 g means normal gravity. 0.5 g means half the normal force.

High speed protection limits the aircraft's speed to avoid exceeding structural limits. It works by freezing the auto trim to prevent unwanted adjustments.

When the load factor exceeds 1.3 g, the Trim Hydraulic System (THS) limits the nose-up trim to a maximum of 2° nose down, regardless of the actual setting.

When the bank angle exceeds ± 33 °, the THS also limits the nose-up trim to a maximum of 2° nose down.

In ground mode, the THS limits the nose-up trim to 2° nose down whenever the load factor is higher than 1.3 g or the bank angle exceeds ± 33°.

The maximum nose-up trim allowed by the THS is 2° nose down when the load factor exceeds 1.3 g or the bank angle exceeds ± 33°.

These limits are important for maintaining safe flight control during demanding maneuvers, ensuring the aircraft remains within safe operating boundaries.

When autopilot is engaged, a force is applied to the sidestick, requiring the pilot to overcome it to move the stick.

If the pilot overcomes the force on the sidestick, the autopilot disconnects, giving full control back to the pilot.

With autopilot engaged, the sidestick movement is limited. The pilot can only move the stick within a certain range before the autopilot disengages.

Even with autopilot engaged, all safety protections remain active, like preventing exceeding the aircraft's limits.

The autopilot's commands are limited by the PRIM (Primary Flight Control Computer) to ensure flight safety.

A special operating mode of the satellite, possibly related to a change in its status or activity. This mode may be activated during specific conditions, such as aircraft landing or when the satellite reaches a certain orbital position.

The satellite's typical or standard operating mode. This is the default mode when the satellite is not in any special or activated operation.

The path the satellite follows around the Earth. It takes minutes for the satellite to complete one orbit.

A specific coordinate system used to designate a satellite's position in the sky. The satellite might pass over the 100th RA, indicating a particular location in its orbit.

The ability of the satellite to capture images of Earth. This satellite is described as high-resolution, indicating it can take detailed pictures.

The Trim Hydraulic System (THS) is temporarily disabled when the aircraft reaches 100 feet above ground level, allowing manual pitch control during landing flare.

At 50 feet altitude, the aircraft automatically applies a slight pitch down elevator input to help maintain a stable descent while landing.

In Flare mode, the pilot needs to apply a gentle nose-up action on the stick to maintain a controlled descent for landing.

The pilot applies nose-up action to counteract the slight pitch-down input automatically initiated at 50ft, helping to control the final flare before landing.