IRIS TEXAN II - Flight Control System

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FOR SIMULATION USE ONLY – NOT A TRAINING AID
INTRODUCTION
The information contained in this section describes characteristics of the aircraft
during specific phases of flight.
Rather than a systems description or particular training technique, the information
provided describes peculiarities which may be encountered in mission oriented
operation of the aircraft.
The flight characteristics described in this section are based on actual flight test
data.
Where actual flight tests have not been performed, or analyses have not been
completed, the information will be identified as projected data.
FLIGHT CONTROL SYSTEM
CONTROL SYSTEM FORCES
The aircraft incorporates a reversible flight control system.
This means the aerodynamic forces are fed back to the pilot from each control
surface through a system of push rods, cables and pulleys.
A bobweight and downspring are incorporated into the elevator control system to
increase the force in the pitch axis. The bobweight increases pitch force as G forces
are increased during maneuvering flight conditions, while the downspring increases
the pitch force about the trim speed in steady state flight conditions.
Pitch force during manoeuvring flight conditions is approximately 9 pounds per G at
the aft center of gravity and 12 pounds per G at the forward center of gravity.
Lateral and directional control forces increase proportionally for a given control
deflection as airspeed increases.
TRIM SYSTEM
The three-axis electric trim system is effective in trimming each axis throughout
the flight envelope of the aircraft. The trim rate in each axis is constant throughout
the airspeed envelope of the aircraft.
As airspeed increases, trim appears to become more effective. This phenomenon is
particularly noticeable in the roll and yaw axes, and pulsing the trim control is
necessary to avoid over-trimming at higher airspeeds.
At forward centre’s of gravity, near full-up pitch trim will be required at final
approach speed with 3-degree approach power.