FWC and DMC: new features

 

By Michel Palomeque

 

1. INTRODUCTION

This presentation is a summary of all the main general improvements, which are already implemented, in the latest FWC or DMC standards for the A330/A340 aircraft family or which will be implemented in the next FWC or DMC standards for the A320 aircraft family.

For the A330 aircraft, the FWC (modification 46511) is called K3.1 and the DMC (modification 46532) is called V110. These are certified since May 1998.

For the A340 aircraft, the FWC (modification 46257) is called L7 and the DMC (modification 46237) is called V510. Both are certified since July1998.

For the A319/A320/A321 aircraft, the FWC is called E3 and the DMC is called V40. Both should be certified in April 1999.

 

2. GENERAL IMPROVEMENTS AFFECTING A320/A330/A340 FAMILIES

2.1. Positive engine relight

All aircraft.

Experience has shown that it was difficult to determine the end of the engine starting sequence when in high stress situations because of a dual engine failure.

A new indication is now displayed on the ECAM engine page when the engine is successfully started either on ground or in flight:

AVAIL is displayed in the center of the N1 indicator at the same place as the REV indication.

AVAIL is displayed in green steady on ground or pulsing in flight for a few seconds when the engine is at or above idle.

2.2. V1 autocall out

All aircraft (new DMC must be installed). Optional modification.

A new synthetic voice “V ONE” is triggered at V1 speed during takeoff roll.

The FWC compares the V1 value coming from the FMGC and the aircraft speed.

This audio message is synchronized with the V1 indication displayed on the PFD.

2.3. Protection against undue slats/flaps extension

All aircraft.

A new red warning is now triggered when the slat/flap lever is not in the zero position when altitude is above 22000ft.

This new ECAM warning is F/CTL FLAP LVR NOT ZERO

2.4. Enhanced speed brake

All aircraft.

SPD BRK memo changes color from green to amber when the speed brakes are commanded to extend and the engines are not at idle.

A new caution is now triggered when this memo is amber for more than 30 seconds.

This new ECAM caution is F/CTL SPD BRK STILL OUT.

2.5. Dual input audio message

All aircraft (for the A330/A340, FCDC L14 must be installed). Optional modification.

A “DUAL INPUT” audio message is triggered when both sidesticks are simultaneously deflected for a certain time. The timing of the audio message has been adapted on the A319/A320/A321 and A330/A340 families due to the different system architectures: in all cases, the message is triggered after the illumination of the glareshields lights.

The aural warning will only be triggered if the dual input situation is prolonged.

 

The “DUAL INPUT” audio is repeated every five seconds. It has the lowest priority of all the audio (voice) messages but can be generated simultaneously with any other non-voice audio warnings.

When the priority pushbutton is pressed on either sidestick, the warning is cancelled except if it is already started. It stops after 5 seconds.

2.6. Vbar indication

All aircraft. Optional modification.

The aircraft standard symbol is replaced by a specific aircraft symbol: inverted “V”.

A Vbar replaces the pitch and roll crossbars.

With the HDG-V/S modes, Vbar symbol is displayed instead of conventional crossed bars.

With the TRK-FPA modes, Vbar symbol is associated to the flight path vector instead of the flight path director being associated to the flight path vector.

 

 

2.7. EGPWS

All aircraft. (New DMC must be installed)

The indications, warnings and cautions associated to the EGPWS are now implemented in these standards of FWC.

GPWS TERR DET FAULT can be triggered if the EGPWS is inoperative: the basic GPWS modes 1 to 5 are still operative.

The aural warning “TERRAIN AHEAD, PULL UP” or “TERRAIN AHEAD” associated with an indication “TERR AHEAD” either red or amber can be triggered when a terrain is detected ahead the aircraft by the EGPWS system..

2.8. FMA/V/S target

All aircraft (new FMGC must be installed).

A new triple click is triggered when either the FMA/V/S target is not held by the AFS, or when the AFS mode sequence is not due to an intended crew action.

If the crew modifies the ALT target while capturing the previously selected level, white boxes are displayed around FMA legend with a 10s duration indicating a mode switching to V/S (target synchronized on current V/S).

If the crew does not confirm this ALT target change within 5s, a triple click is generated and the V/S FMA legend is reboxed for 10s.

The crew can confirm this ALT target change by either pulling the ALT knob or by setting a new V/S target (level off included) or by pushing the ALT pushbutton.

2.9. FANS/ATSU modification

All aircraft (FANS must be installed).

Several new alerts associated to the FANS/ATSU are created:

DATALINK VHF3 DATA FAULT: this ECAM caution is triggered when the VHF datalink is inoperative.

VHF3 VOICE memo: This indicates that the VHF3 transceiver operates in voice mode, therefore datalink communications are interrupted.

HF VOICE memo: This indicates that the VHF3 transceiver operates in voice mode, therefore datalink communications are interrupted.

GND HF DATA LINK memo: This indicates that the HF transceiver operates in datalink mode.

 

 

3. GENERAL IMPROVEMENTS AFFECTING A320 AIRCRAFT FAMILY.

 

3.1. Derated takeoff

A320 (already on A330/A340). Optional modification.

A derated takeoff is defined as a takeoff at a thrust setting less than the maximum takeoff thrust.

Six derate levels are defined which correspond to 4,8,12,16,20 and 24% decrease from the maximum takeoff thrust.

Derated takeoff may be used when the takeoff weight is limited by VMCG, enabling benefit to be taken from the reduction in VMCG associated with the new rating.

DRTO is displayed on the PFD indicating that a derated takeoff is performed.

3.2. Metric altitude

A320 (already on A330/A340). Optional modification.

If metric reference is selected on the FCU, two additional symbols are displayed on the PFD.

The target altitude or selected flight level is displayed in meters on the right top of the PFD.

The actual aircraft altitude is displayed in meters on the right bottom of the PFD.

3.3. Electrical emergency configuration

A320 only.

An electrical modification associated to a new RAT has been defined for the A320 aircraft.

When embodied, this allows the A320 aircraft to have the same behavior as the A319/A321 aircraft: the RAT can supply the aircraft even if the landing gears are extended.

Without this modification, in electrical emergency configuration on the A320, when the landing gear are down, the RAT is not able to supply the aircraft and so, the batteries only can supply the aircraft.

This requires the crew to extend the landing gear only five minutes before landing to avoid excessive battery discharge.

If the landing gear is extended more than five minutes before landing, the ECAM warning requests the crew to retract them and to reset the emergency generator.

The ECAM warning is modified to reflect the new behavior associated to this RAT modification.

 

4. GENERAL IMPROVEMENTS AFFECTING A330/A340 AIRCRAFT FAMILY.

4.1. Elevator redundancy lost

A330/A340 only (FCDC L15 must be installed).

The associated procedure is now displayed on the ECAM.

This ECAM caution is triggered in case of dual failure when a third failure affecting the flight control system may lead to degraded pitch control or pitch mechanical back up.

Depending on the failures, an aileron preset can occur: the ECAM procedure covers both cases (aileron preset and aileron not preset).

4.2. Parking brake

A330/A340 only (BSCU 7A must be installed)

A new ECAM warning “BRAKES PARK BRK LO PR” is now triggered when the parking brake pressure is low.

4.3. Fuel transfer

A330/A340 only.

When either the center to inner transfer or the outer to inner tank transfer is manually selected, MAN XFR COMPLETED is no more triggered at the end of the transfer requesting to select the pushbutton in auto position. Once in auto position, the ECAM requested to select the manual transfer: this caused the crew to cycle between the automatic and manual transfer.

4.4. Automatic rolling takeoff (Rolls Royce engines)

A330 only (For Rolls Royce engines, FADEC A9 must be installed).

An automatic rolling takeoff logic is now implemented in FADEC A9: this feature ensures that the thrust is progressively set and that full thrust is automatically applied when the speed is greater than 50 knots.

This protects the engine against the fan stall phenomenon.

A new FADEC logic is now available to monitor this function and “ENG XWIND PROT FAULT is now triggered on the ECAM if this function is not available on ground to ensure this automatic rolling takeoff or if this function is spuriously activated in flight (engine slow response).

4.5. LP shaft sensor (Rolls Royce engines)

A330 only (Rolls Royce engines with FADEC A9).

A new ECAM warning “ENG LP SHAFT PROT LOST” is now triggered when the LP shaft sensor is faulty.

This was previously covered by the caution ENG MINOR FAULT.

4.6. Stability bleed valve (Pratt & Whitney engines)

A330 only (Pratt & Whitney engines with FADEC SCN 6B)

The stability bleed valve is now monitored: when it is failed open, the following ECAM warning “ ENG FADEC SYS FAULT” on ground or “ ENG CTL SYS FAULT” in flight are triggered.

The procedure associated to these cautions recommends the crew to not use the reversers: if reversers are used, damage can be caused to the engine nacelle.

4.7. Oil low pressure

A330 only. (For RR engines, the FADEC A9 must be installed).

The procedure is changed and does not require anymore the crew to crosscheck the oil pressure indication.

4.8. All engine flame out

A330/A340 only.

The procedure of the ECAM warning “ENG ALL ENG FLAME OUT” is changed to indicate that when on APU bleed, all the engines can not be started at the same time.

It is now recommended to attempt to restart the engines in sequence.

 

4.9. Adapted Go-Around

A340 only. Optional modification.

On the A340, during go-around, if an external engine is failed or at low power, the go around thrust on the opposite engine is reduced automatically.

Thus, the minimum control speed (VMC) is reduced.

When the Adapted Go-Around (AGA) is active, an “A” is displayed on the right top of the N1 indication.

4.10. Hundred above

A330/A340 only (new DMC must be installed). Optional modification;

A new synthetic voice can be activated upon minimum descent altitude or minimum height reference in non-precision approach.