A320 FCU – flight control unit

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FCU is par of A320 glareshield

A320 FCU : Flight Control Unit #

FCU flight control unit panel is part of a320 Glareshield

FCU Windows #

Speed/Mach Window #

The SPD/MACH Window displays the selected speed/Mach.

Manage Speed Light #

When the speed selector is pushed, FMGS managed speed engages, the managed speed light illuminates, and dashes appear in the SPD/MACH window

Heading/Track Window #

The HDG/TRK Window displays selected HDG/TRK. Displays dashes when a managed lateral mode is engaged.

Lateral Light #

The LAT Light illuminates to indicate managed lateral mode is either armed or engaged.

Flight Director Display Mode #

The Flight Director Display Mode indicates that the flight director is in either HDG-V/S or TRK-FPA display mode.

Altitude Window #

The ALT Window displays altitude selected with the altitude selector. The window never displays dashes, even when CLB or DES is engaged.

Vertical Speed/Flight Path Angle Window #

The V/S / FPA Window displays the selected vertical speed or flight path angle. It normally displays dashes when not in V/S or FPA mode.

FCU Selectors A320 #

Speed/Mach Selector #

The Speed/Mach Selector when rotated, changes the value displayed in the SPD/MACH window.

When pulled, the selected speed displayed in the SPD/MACH window engages. If the selector is pulled when the SPD/MACH window contains dashes, the window displays the current airspeed.

When pushed, FMGS managed speed engages, the managed speed light illuminates, and dashes appear in the SPD/MACH window.

Altitude Selector #

The Altitude Selector changes the altitude displayed in the ALT window. The Inner Selector rotates to change altitude value. The Outer Selector provides selection of 100 or 1000 foot increments.

When the Altitude Selector is pulled, OP CLB or OP DES mode engages. When pushed, CLB or DES mode engages, and the LVL/CH light illuminates.

Heading/Track Selector #

The Heading/Track Selector when rotated, changes the value displayed in the HDG/TRK window. When pushed, NAV arms or engages and the LAT light illuminates.

When pulled, the selected heading/track displayed in the HDG/TRK window engages.

If a heading is selected prior to pulling the selector, the airplane turns in the shortest direction to the selected heading. If a heading is selected after pulling the selector, the airplane turns to the new heading in the direction the selector is turned. If the selector is pulled during a turn, the airplane rolls out on the existing heading.

Vertical Speed/Flight Path Angle Selector #

Vertical Speed/Flight Path Angle Selector when rotated, changes the VS or FPA displayed in the V/S / FPA window. The vertical speed range is from ± 6000 FPM. The FPA range is from ± 9.9°.

When the selector is pulled, V/S or FPA engages. When pushed, the airplane levels off.

NOTE

When engaging a vertical speed or flight path angle, the selector must be pulled within approximately 45 seconds, or the selection is lost and dashes are redisplayed.

FCU Buttons – A320 #

Speed/Mach Button #

The SPD/MACH Button when pushed, changes the value in the SPD/MACH window from airspeed to Mach, and vice versa.

HDG-V/S/TRK-FPA Button #

The HDG-V/S/TRK-FPA Button changes between heading/vertical speed and track/flight path angle display modes.

When HDG V/S mode is selected, HDG appears above the HDG/TRK window and V/S appears above the V/S FPA window. Flight director command bars can be displayed on the PFD.

When TRK FPA mode is selected, TRK appears above the HDG/TRK window and FPA appears above the V/S / FPA window. Flight path vector is displayed on the PFD, and the flight path director can be displayed on the PFD.

Metric Altitude Button #

The METRIC ALT Button displays the FCU altitude in meters on bottom of lower ECAM.

Auto Pilot Buttons #

The AP Buttons engage/disengage selected autopilot. Autopilot guidance modes are selected on the FCU and MCDU. Engagement is confirmed by the flight mode annunciation (FMA) on the PFD.

The autopilots utilize ailerons, rudder, spoilers, and elevators to achieve the desired flight profile. Rudder inputs, yaw damping, and rudder trim are computed by the FACs and are automatic when an autopilot is engaged.

The autopilot also provides inputs to the nose wheel steering unit during the ROLL OUT mode on an autoland approach.

LOC Button #

The LOC Button arms, engages, or disengages the localizer mode. It illuminates the managed lateral light. Dashes appear in the HDG/TRK window when LOC* or LOC engages. It takes a minimum of 3 seconds after arming for the LOC to arm.

A/THR Button #

The A/THR Button arms or disengages the auto thrust system.

The autothrust system is an integral part of the autoflight system. When engaged, the autothrust mode is determined by the active vertical mode of the autopilot/flight director system.

If both autopilots and flight directors are off, the default mode of the autothrust system is SPEED. Autothrust modes are indicated in the first column of the FMA. Refer to ATHR FMA definitions for detailed autothrust information.

Expedite Button #

The EXPED Button engages the EXPED mode to reach the altitude set in the altitude window with maximum vertical gradient. Automatically engages managed speed. Airspeed is green dot during climb, and .80M/340 KIAS during descent. To disengage EXPED, select new vertical mode or selected speed.

EXP CLB is not recommended above FL 250 because the Mach corresponding to green dot is too low

APPR Button #

The APPR Button Arms, engages, or disengages the following modes:

LOC and G/S modes if an ILS approach has been selected via the flight plan or RADIO NAV page or RMP (takes a minimum of 3 seconds after arming for the LOC and/or G/S to engage in the capture mode).
APP NAV, FINAL, and FINAL APP modes if a non-precision approach has been selected from the MCDU database.

CAUTION

Do not arm the ILS APPR mode above 8000 feet AGL. Radio altimeter signals are not available above this altitude and with the APPR button armed, the autopilot disengages at glideslope capture and the flight directors revert to HDG-V/S.

NOTE If the LOC or APPR button is selected on and the ILS/LS button is not selected, and an ILS approach is entered in the flight plan or the RADIO NAV page, ILS flashes amber on the PFD. If the ILS/LS and APPR buttons are selected on when a non-ILS approach is selected in the flight plan, V/DEV flashes amber on the PFD.

NOTE

If a VOR or NDB approach has been selected in the database, the LOC and APPR buttons will not arm for localizer or glideslope capture, even if the ILS frequency is manually tuned. An ILS approach must be selected via the flight plan page.