Targetware: Flight Model Development

Targetware ACM File Guide

PART REFERENCE: Control

The control type requires the following entries,

chord = fraction of the airfoil chord, usually 0.2 to 0.3
span = fraction of the airfoil span

While you don't specify the span of any part (only the area), the span and chord entries determine the surface area of the control surface for lift and drag calculations when the controls are deflected.  In order that the control forces give the correct response, it is recommended that all areas that have control surfaces hinged to them be modelled as separate parts so that their aerodynamic centers can be located properly.  For example, don't model a wing with both a flap and an aileron as one part with two surfaces.  Instead, model the wing in two parts, each with one surface.  That way, the forces from the flaps will be inboard of the forces from the ailerons.

yaw_response = 0
pitch_response = -1
roll_response = 0

These entries determine about which axis the control will act.  In this case, it's an elevator control as it affects pitch response.  It is negative, because the tail surface is behind the wing, so that pulling back on the joystick gives a nose up reaction.

max_deflection = deflection angle in degrees down
min_deflection = deflection angle in degrees up
deflect_time_max = time to deflect in seconds, time to neutral in seconds
deflect_time_min = time to deflect in seconds, time to neutral in seconds

The deflect time is important in determining how an airplane handles.  If the control surfaces deflect too fast, a pilot induced oscillation will result.  Actual control forces can be greater than those imposed by a joystick, so it becomes necessary to limit how quickly the virtual controls are able to be moved.  It can also be useful for reducing the effects of joystick spiking.  One should set the travel rates in accordance with average angular accelerations of the airplane at slower speeds.

max_ias = meters per second

This is the indicated airspeed beyond which full control deflection can no longer be maintained due to excessive air pressures.