The autopilot will be engaged automatically when you load the aircraft, although none of its hold modes are active. In the real Draken the master switch was sealed in the ON position and only switched off in an emergency.

The reason for this is that the autopilot in Draken handles the pitch damping function, making the aircraft less susceptible to PIO (pilot induced oscillation) that plagued the early versions of Draken. The damping mode was supposed to be switched on at all times. In this simulation pitch damping is actually a part of the FDE and can not be disabled.

The altitude and attitude hold modes will disconnect automatically under certain conditions, see Override conditions.

Autopilot modes

Pitch damping mode (DÄMPN)

This is the default mode and should always be on in manual flight to prevent PIO (Pilot Induced Oscillation).

Attitude hold mode (ATTITYD)

In this mode the aircraft will hold the current pitch attitude. If the bank angle is less than 15 degrees when this mode is activated, the wings will also be leveled. The pitch control will adjust pitch up/down in 1 degree increments.

The SVÄNG (turn setting) knob on the autopilot control panel will bank the aircraft left/right in 15 degree increments.

Altitude hold mode (HÖJD)

In this mode the aircraft will lock to the current altitude. If the bank angle is less than 15 degrees when this mode is activated, the wings will also be leveled. The altitude hold light HÖJDV on the front panel will flash until altitude is stable, then it will show a steady light.

The SVÄNG (turn setting) knob on the autopilot control panel will bank the aircraft left/right in 15 degree increments.

In the transsonic speed range (M 0.95–1.05) the autopilot will change temporarily to attitude hold mode, and the altitude hold light HÖJDV will flash. When the aircraft exits the transsonic speed range, the autopilot will change back to altitude hold mode. The mode indicator on the autopilot panel will not change.

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Fig. 59 - Altitude hold light

Trim knobs

The Roll Trim and Yaw Trim knobs will adjust roll and yaw trim in 10 % steps. Trim setting will affect the control surfaces regardless of the autopilot status, and is added to the current roll/yaw attitude in altitude/attitude hold modes.

Override conditions

In altitude and attitude hold modes the autopilot will disconnect automatically if the joystick is moved abruptly, if one of the attitude indicators is caged, or if G force is above 4 G or below -0.5 G. The autopilot warning light and the master warning will then be lit. There is no acoustic warning.

To reconnect the autopilot and reset the warning lights, press one of the mode select buttons on the autopilot control panel.

The G force override function can be tested with the AUTOPILOT g-TEST switch, which is located on the right knee panel. Pressing the switch upwards (+) simulates a high positive G condition, and vice versa.

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Fig. 60 - Autopilot override test switch