ENG start valve fault after ENG failure in A320

[IFLY_INDIGO]

In simulator I have noticed that after ENG FAIL, we do get ENG START VALVE FAULT and the action asked is to turn the X-BLEED ON.

I don't get it. why this fault appears when engine has failed ?

[vilas]

This is irrelevant erroneous ECAM notification. Just ignore it no need to open cross bleed.

[Goldenrivett]

I don't get it. why this fault appears when engine has failed ?

ECAM logic thinks you are attempting an Engine Relight (in flight).
With the ENG Mode SEL ...IGN, FADEC will attempt a relight and ECAM asks for the X_BLEED ... OPEN.

As vilas says, you may ignore it as you will secure the engine first and consider a relight at a later stage.

[IFLY_INDIGO]

nice explanation!

Thanks.

[Rocket3837]

Start valve fault in sim

Hi everyone,
If an engine fails the FADEC commands engine relight whether in aircraft or SIM.....
However, in SIM, because the "eng fail" fault is inserted by instructor, it will prohibit the engine from restarting as long as the eng master as is ON.

[vilas]

This is actually an ECAM glitch. There's no logic really because if you see in FCOM abnormal procedures Engine 1(2) fail there is no mention of start valve fault.

[ZFT]

Rocket3837

You've lost me.

[IFLY_INDIGO]

is it SIM fault or will it happen in aircraft also in case of a real engine failure?

[Goldenrivett]

will it happen in aircraft also in case of a real engine failure?

According FCOM - yes. (Though I've not had a real engine failure on A320).

This is actually an ECAM glitch.

ENG 1(2) START VALVE NOT OPEN
If opposite engine running : - X BLEED .....ON
FLT Phase INHIB 3,4,5, 7, 8.

If taking off with APU Bleed on (for Packs), then you shouldn't see this fault reported.
If taking off without APU Bleed, then ECAM is reminding you that the engine couldn't be cranked over by the starter motor unless you opened the X Bleed.

I don't know why the message isn't removed when the ENG Master Switch is put to off.

[Escape Path]

Originally Posted by Rocket3837

Hi everyone,
However, in SIM, because the "eng fail" fault is inserted by instructor, it will prohibit the engine from restarting as long as the eng master as is ON.

It will be ON though, as the relight attempt is started as soon as the ECAM engine failure is triggered.

I don't know how the attempt will ever be successful because if you're taking off with APU off there's no bleed pressure to the starter. The only thing I can think of is by mere windmilling but the rotor speeds will perhaps be too low too quickly to actually accomplish a relight.

Anyone with an explanation of how an auto-relight will be successful?

[HJ2334]

We train to attempt a relight if there are no signs of damage, such as fire, seizure or vibration. Auto-relight will normally restart an engine due to a simple flameout. A flame out can occur when the combustion process stops due to things like Fuel starvation,Heavy rain, icing,ice crystals,Engine stall...etc etc. A relight is not always 100%!!!

I've never had a successful relight when in the sim. Therefore carried on with ECAM actions. Found this video useful on youtube of Engine Failure as I was struggling going through the manuals.

https://www.youtube.com/watch?v=KyWBCiQYRVM&t=206s

[Rocket3837]

I don't think it is a Sim glitch...
After inserting the "eng fail" fault,the FADEC will attempt a restart (eng master sw still ON), but due to low aircraft speed, the FADEC will use the starter motor and thus asks for X-Bleed.

You will not get "start valve fault" if APU is supplying the bleed sys.

If "eng fail" is inserted at hi spd (say 300 kts) windmilling start will be selected by FADEC and you will not get "start valve fault".....

IMHO if the "eng master sw" is selected off w/o delay after inserting the fault, then you will not get the starter fault...
Thanks

[vilas]

Well not exactly a glitch but irrelevant advice at that stage. According to Airbus FADEC switches on both igniters when it senses an engine failure. Below 400ft if the relight doesn't take place before N2 drops below 40% then igniters are switched off. And a complete engine relight in flight procedure needs to be carried out. Therefore it might be triggering start valve not open message and suggest a crossbleed start. But before you do that you need to shut down the engine and clean up the aircraft and resume climb. Therefore it is too premature.

[Goldenrivett]

vilas

Well not exactly a glitch but irrelevant advice at that stage.....Therefore it is too premature.

After take off, it is only displayed in flight phase 6 (i.e. >1500 ft).
Using the design logic available to Airbus, when would you prefer to have the advice reported?

[BoeingDriver99]

I just had this occur in the sim and the FO wanted to open the x-bleed and I wanted to disregard the ECAM as per above. Does Airbus have anything to say on this? On the WIN website there is nothing about it. Something more solid than pprune would be nice

Also, how come the ECAM doesn't go away naturally once the Master is off?

If we were on the ground, hadn't selected APU bleed on, set Eng Mode sel to IGN/Start and then Eng Master ON we would get the ECAM but if we set the Master back to Off the ECAM would go away right? So EFATO you have one engine off/ corresponding eng Master Off/Apu bleed off/Eng mode sel IGN/Start. How come the ECAM persists?

Another example: If you turned off a hydraulic pump and got an ECAM for low pressure and then turned the pump back on the ECAM would disappear once the conditions were no longer present.

Thanks

[vilas]

ECAM doesn't disappear but you clear it after actions are completed. That gets the status page. You can always recall ECAM.

[FlightDetent]

Since about 2 years I changed my mind and just perform the action if there was no damage, and when we actually get to that line. Partly for standardization reasons, keeping the ECAM drill simple without personal preferences.

But mostly to avoid pointless debriefing moments in case th checker considered it necessary. It's much easier to explain against 'you did not really needed that' than the other way around.

No harm done. Just make sure to follow the FCTM and confirm the failure before rushing for the E/WD action lines.

[vilas]

The problem is you trigger engin fail without damage from the IOS and it triggers an ECAM massage Engine start valve fault. At that stage it doesn't make any sense. The failure has nothing to do with start valve. May be it's erroneous link to engine start failure with start valve fault. It's confusing.

[BoeingDriver99]

Do you know what might occur in the real aircraft with a real engine failure?

Also I’m still confused as to why the ECAM thinks you are attempting a start at this point - you have selected
Mode SEL - IGN
THR LEVER - IDLE
Master - OFF
Fire P/B - as req’d

and cleared the first ECAM.

You are not attempting a start at this point. Also I would imagine that you won’t get it if you’ve pushed a Fire P/B as you have now told ECAM the engine is damaged and thus will keep X-Bleed closed.

[CrazyStuntPilot]

The START VALVE FAULT is latched by Flight Warning Computer logic; this is why it does not disappear when the fire pushbutton switch is pushed.