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					                                                        Airbus Automatics
FMGS The Flight Management, Guidance and Envelope System (1.22.10 p1) is pilot interactive (honest) and contains the following units: 2 FMGC,
       3 MCDU, 1 FCU and 1 FM source set. There are 2 other crew interfaces, the thrust levers and the EFIs.

FMGC The Flight management Guidance and Envelope Computer has 4 main parts:
       1. The FM part controlling navigation, flight planning, performance, NavRad, and display driving.
       2. The FG part controlling AP command, FD command and Auto-thrust command.
       3. The FE part controlling speed envelope, monitoring FG/FE parameters, windshear and aft cg detection and computation of GW and CG
       4. The FIDS part providing maintenance data functions and interface with the CMC.
       Each FMGC has its own database containing 2 fields; one unmodifiable core of performance and navigation data and one pilot created
       navigation data, which may include 20 waypoints, 20 navaids, 10 runways and 5 routes. The main database is updated every 28 days.
       The FMGC is the basic means for navaid tuning: normally navaids being auto-tuned by the FMGC (each FMGC controlling its onside
       receivers), however pilots can manually tune navaids through the MCDU for visual display.

MCDU The MCDU is the long term interface between the FMGC and the pilot and allows:
       1. Definition of an overall Flt Plan.                2. Display, selection and modification of flight management info.
       3. Selection of specific FM functions.               4. Peripheral data display, inc ACARS.
       5. Back-up navigation.
       Pilot entries and modifiable data are displayed in large font.

FCU The FCU is the short term interface between the FMGC and the pilot and allows:
        1. Engagement of the AP and A/THR.
        2. Selection of the required guidance modes.
        3. Selection and display of manual guidance targets.

FM source set This selector allows switching of the FMGC data to the offside MCDU and EFIs display in case of one FM failure. MCDU 3 is not able
to operate as Back Up Nav even when it replaces MCDU 1 or 2. The BUN mode is only accessible on the MCDU MENU page if the FM source is set
to NORM position

FD Roll, pitch and yaw bars are only in view at the same time during align. Below 30ft during TO or landing when a localiser is available, the
vertical bar is replaced by a yaw bar index. The FDs are auto-engaged at FMGC power up on the ground or in flight. On the ground, 1FD2 is
displayed on PFD, no FD bars in view and FCU windows are dashed: directions are displayed when a mode is active. If 1 FMGC is not valid, the
remaining FD is displayed on both PFDs. FDs are occulted when aircraft pitch or roll limits are reached or when ROLL OUT mode is engaged. FD
bars flash for 10 secs when ALT* mode is lost after 250ft change to FCU altitude or when in APPR mode FD reverts to VS. FD bars flash
permanently when reception of glideslope data is lost above 100ft RA. The roll FD bar flash for 10secs when FD reverts to HDG mode in APPR or 1
AP/FD is engaged while both AP/FD were previously off. The roll bars flash permanently when reception of the localiser data is lost above 15ft RA.


        Modes There are four possible modes of operation: 1: normal/dual mode, 2: degraded/independent mode, 3: degraded/single mode
        and 4: degraded/back-up navigation mode:
          1. DUAL Both FMGCs are synchronised, achieve their own computations and exchange data through a crosstalk bus. One FMGC is auto-
          selected as master. 3 MCDUs are supplied; #1 and #2 act with each FMGC, #3 acts as a spare and monitors ACMS, CMS, etc. Both
          MCDUs act independently but entries can be made from either and are auto-transmitted to the other and applied to both FMGCs.
          2. INDEPENDENT If a mismatch occurs, the system auto-degrades and cannot be corrected by resynchronisation. Each FMGC works
          independently (IND). Entries on one MCDU are not crosstalked to the others.
          3. SINGLE If one FMGCs fails, single mode occurs. The FM source selector transfers the remaining FMGC data to the offside MCDU and
          EFIs. All peripherals are still driven by the good FMGC and MCDU data is still crosstalked.
          4. BACKUP If both FMGCs fail, navigation is provided by the IRS and MCDU which has memorised the flight plan. The Back Up NAV
          mode is selected on the MCDU menu page. Flight Planning, Aircraft Position using onside IRS or IRS3, F-PLN display on ND, F-PLN auto-
          sequencing and limited lateral revisions are provided. NO AP/FD NAV mode is available.

        Switching The FM switching in the case of one FMGC failure for the MCDU and EFI displays is through the FM source selector at the
        front of the pedestal. In the case of MCDU #1/2 failure, MCDU #3 is brought on line by selecting the affected MCDU brightness switch to
        OFF; MCDU #3 then replaces the failed MCDU.

        Thrust levers have the following functions:
             1.   Manual selection of engine thrust.
             2.   Arming/activation of A/THR.
             3.   Reverse engagement.
             4.   TOGA mode engagement.
             5.   With A/THR off, the thrust levers directly command thrust.
             6.   With A/THR active, the FG commands thrust, limited to max thrust lever position, according to the vertical mode logic.
             7.   At the idle detent, pulling reverse selects idle reverse and then selects reverse thrust.

FM        performs Navigation, Flight Planning, Performance, Management of Displays. The essential navigation functions are Polar navigation,
Radio Nav tuning, IR alignment and Position computation using ADR, IR, VOR/DME, ILS, GPS, MLS. Each FMGC receives 3 IRS positions and
computes a mean weighed average position called the MIX IRS position. Each FMGC computes its own radio position using its FM onside selected
navaids (1.22.20 p2).

FG           FG controls the AP, FD and A/THR through either managed or selected modes. In managed modes the aircraft is steered along a profile
defined by MCDU data entered by the pilot yielding guidance targets computed by the FM. In selected modes the aircraft is steered to target
values selected by the pilot in the FCU. The selected modes are HDG-V/S, OP CLB/DES, TRK-FPA, ALT/ALT *, FCU reference: ALL others are

FE       The FE part of the FMGS acquires and monitors parameters used by the FE and FG parts, computes characteristic speeds, computes
back-up weight and CG, monitors aft CG and detects windshear.

AP       AP functions are the stabilisation of the aircraft, flight path control, autoland and go-around. The AP generates commands via the
PRIM/SEC flight control computers and BSCU (Braking/Steering Control Unit) to position appropriate control surfaces and the nose wheel. AP 1/2
can be engaged on the FCU provided that the aircraft has been airborne for >5sec and:

                    1. 2 ADIRS are operative.                             5. 1 RA operative in APPR phase.
                    2. FG operative.                                      6. Related ILS operative in LOC arm or LAND arm
                    3. FM operative, except if LAND < 700ft or GA         7. 1 PRIM and 1 SEC active.
                    4. 1 FCU channel operative.                           8. 1 rudder trim and pitch trim operative, except if
                                                                          LAND < 200ft.

If one AP is engaged with both FDs off, the AP engages in HDG-V/S or TRK-FPA mode. If the AP is engaged with at least one FD on, the AP
engages in the current active mode. At AP engagement, the load thresholds on the side stick controllers and rudder pedals are increased. AP may
be engaged in selected modes in case of dual FM failure. The AP will disengage when:

                    1. The take-over pb on side stick is pressed.         5. TLA above MCT detent with aircraft on the
                    2. The corresponding AP pb switch on FCU is           6. When reaching MDA-50ft in APPR and a non-ILS
                    pressed.                                              selected.
                    3. A certain force is applied to the sidestick.       7. If one of the engagement conditions is lost.
                    4. The other AP is engaged, except in GS, LOC or      8. In NL: HSS or alpha prot active or AoB > 45°.
                    GA modes.

An Autoland red warning in LAND mode occurs for:

                    1. AP OFF <200ft                                      3. Excessive G/S deviation between 100 & 200ft
                    2. Excessive LOC deviation between 15 & 200ft         4. No data from ILS at < 200ft
                    5. 15ft differential between RadAlts

A/THR       The A/THR ensures that a specific thrust is maintained in THR mode, the aircraft speed is maintained in SPD/MACH mode and that thrust
protection is provided against alpha floor. The A/THR system may be used alone or with AP/FD. When used alone the A/THR, without AP/FD,
always controls the speed. If the A/THR system is used with AP/FD, the A/THR mode and AP/FD pitch modes are linked together if the AP/FD
controls a vertical path then A/THR controls speed or if the AP/FD controls a speed, the A/THR controls thrust. As part of the FMGC, the A/THR is
always driven by the master FMGC. When 2 APs are engaged or neither AP/FD, A/THR 1 has priority. Setting the THR levers to the idle detent,
disconnects the A/THR. If you press and hold the instinctive disconnect pb on the thrust levers for 15secs, you disarm the A/THR until the aircraft
is totally powered down.

FMA       The 5 columns are: A/THR, Vertical, Lateral, Approach and AP/FD/A/THR status. The engaged modes are displayed in GRN on the first
line. Armed messages are displayed in BLU/MAG on the second line. Special messages are displayed on the third line with first priority to flight
control messages then lower priority messages relating to the FMGS.

Wt & CG The FMGC uses the weight and CG from the Fuel Computer when available. The GW and CG computed by the FE are used as a back-up
in case of dual FCMC failure and to trigger the aft CG caution/warning signals.


The EIS presents data to 6 identical DU: 4 EFIs and the ECAMs. The EFIs are 2 PFDs and 2 NDs. The ECAM presents data to the E/WD and SD.
The 3 identical DMC acquire and process all input signals for display on the EFIs/ECAM. The DMCs have separate channels for EFIs and ECAM
displays. 2 FWC acquire data directly and through the SDAC for alert messages, memo info, aural alerts, voice info and flight phase calculations
which is fed to the DMCs. Normally #1 DMC drives Capt's PFD/ND, #2 DMC drives F/O's PFD/ND and #3 DMC drives the ECAM. A DMC failure is
indicated by a green diagonal line across the screen. DMC 1/2 can replace DMC 3 and the ECAM SD can be transferred to either Capt's or F/O's ND.
The Capt's PFD & the E/WD is always available even after an electrical emergency.

If the upper ECAM DU fails, info is auto transferred to the lower ECAM DU. The system/status page may be recovered either by ECAM/ND
switching to an ND or on the lower ND by holding depressed the SYS button. If the lower DU fails, info may be recovered as for the upper DU. If
the PFD display fails, the ND display is auto replaced by the PFD. PFD and ND can then be toggled by the PFD/ND pb. If after PFD failure, the PFD
display comes back on line, the PFD is latched so disallow irritation switching of display. All switching for EFIs re-configuration after assoc DMC
failure is manual. ECAM reconfiguration from DMC #3 to #1 is automatic although manual follow-up is required. Further re-configuration is
manual. After a dual E/WD and SD failure, the ECAM page can be transferred to the ND by the ECAM/ND NORM rotary switch. After total ECAM
DMC failure, the ENG page is available via the EFIs half of the DMC on the ND through the ND selector. If the ECAM Control Panel failure, The CLR,
RCL, STS, ALL and EMER CANC pb remain operative as they are hard-wired to the FWC/DMC. Access to individual pages is then via the ALL pb
which cycles pages at 2sec intervals.

The ECAM warning/cautions have priority rules such that a level 3 warning has priority over level 2 caution which has priority over a level 1 caution.
Same levels are sorted by the FWC. Types of failure:

          Independent          affects an isolated system or system which consequences for other systems.
          Primary              causes collateral failures.
          Secondary            resultant loss from primary failure.

                                                  Level 3                  Level 2                   Level 1
                        Action?                   YES                      Amber caution             Amber caution
                        Optical warning?          Master Warning flashes   Master caution On         No
                                                  E/WD message             E/WD caution message      E/WD caution message
                                                  Relevant systems page    Relevant systems page
                        Aural warning?            CRC                      Single chime              No

The STS page appears automatically once the crew have cleared all the pages corresponding to the current failure and, reappears during descent
when baro ref is selected on the FCU or when slats are extended, whichever occurs first.

Irritation warnings may be long term cancelled with the ECAM EMER CANC pb (1.31.30 p3). This cancels the present aural warning as long as the
failure is present, the master warning lights go out but ECAM message display is not affected by the selection. Any present caution is cancelled for
the remainder of the flight, the STS page is auto-called and "CANCELLED CAUTION" displayed. The inhibition is suppressed when the aircraft is
next powered up or when the RCL button is pressed for more than 3secs.

Cockpit Overhead Circuit Breakers

 ACP/AMU        Audio Control Panel / Audio Management Unit 1.23.10              FWC             Flight Warning Computer 1.31.05
 CIDS           Cabin Intercom Data System 1.23.20                               LGCIU           Landing Gear Control Interface Unit 1.32.10
 CPC            Cabin Pressure Controller 1.21.20                                PACK CONT       Pack Controller 1.21.10
 DMC            Display Management Computer 1.31.05                              PHC             Probes Heat Computer 1.30.50
 EIVMU          Engine Interface & Vibration Monitoring Unit 1.70.80             PSCU            Proximity Switch Control Unit 1.52.10 p10
 FCDC           Flight Control Data Concentrator 1.27.10                         SDAC            System Data Acquisition Concentrator 1.31.05
 FCMC           Fuel Control & Monitoring Computer 1.28.10                       SDCU            Smoke Detection Control Unit 1.26.10
 FCU            Flight Control Unit 1.22.10                                      VENT CONT       Vent Controller 1.21.30
 FM             Flight Management 1.22.10                                        WHC             Window Heat Computer 1.30.40
 FMGEC          Flight Management Guidance Envelope Computer 1.22.10             ZONE CONT       Zone Controller 1.21.10

c:\…\22AUTOFLT.doc - create: 9 January 1995 - last saved: 14 April 2010