FCU

The flight crew can use two types of guidance for the aircraft. One is a managed guidance from the FMGC, the other uses target values which are manually selected by the flight crew on the FCU.

When the flight crew use target values form the FMGC, this is known as Managed guidance. The FCU display a blank or dashed window in t he appropriate display for the value that is being managed.

Note that at all times the altitude window in the FCU shows the cleared altitude, even if the FMGC is being used to manage the altitude. IN a climb, it acts as an upper limit that the FMGC can not exceed, in a descent it acts as a lower limit.

The FCU has 4 selector knobs that turn, pull and push. Pushing in a selector knob arms or selects a managed guidance mode. Pulling out the selector knob reverts to target values from the FCU being used in a selected guidance mode. Turning the knob changes the target value in the associated FCU window.

Speed/Mach control Area

Lateral control Area

Altitude control Area

SPD/Mach Push Button

SPD/Mach Selector knob

SPD/Mach Window

Managed Dot

Heading Selector knob

Heading/Track Window

Managed Dot

Metric Pb

Shows the selected FCU altitude in meters on the System display

Alt Selector knob

Alt Window

V/S or FPA Window

V/S selector knob

Turning the Speed Knob increments/decrements the FCU selected speed. The SPD/Mach push button changes the FCU selected speed between a Mach value and an IAS value. The SPD/Mach window shows dashes when managed speed target has been commanded. The SPD/Mach Selector knob may be pushed in to command a managed target speed from the MCDU. The SPD/Mach Selector knob may be pulled out to command a selected speed target from the FCU.

Turning the Heading Selector knob increments/decrements the target heading or track target value. The target heading or track target value is shown in the Heading/Track Window. The Heading Selector knob may be pushed in to arm the NAV mode. The Heading Selector knob may be pulled out to engage the HDG/TRK mode. The FMGS can be changed from HDG- V/S to TRK - FPA mode by pressing the HDG/TRK button on the FCU.

Turning the Alt Selector knob increments/decrements the FCU Altitude. The Alt Selector knob may be pushed in to engaged a managed climb/descent mode. he Alt Selector knob may be pulled out to engage the open climb/descent mode.

Turning the V/S selector knob increments/decrements the V/S value or FPA value. The V/S selector knob may be pushed in to engage the V/S mode with zero V/S target.

FCU Buttons

LOC button arms the LOC mode

APPR button arms the Approach mode

ALT button engages the Altitude hold for the current aircraft altitude (A330)

EXPED button engages the expedite climb/descent mode ( A320)

A/P buttons engage the respective A/P

A/THR buttons engage or arms the Auto thrust system

HDG VS / TRK FPA push button swaps the FMGS between Heading and V/S to Track and Flight Path Angle modes