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IFLY_INDIGO
29th Jun 2017, 06:33
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
29th Jun 2017, 09:41
This is irrelevant erroneous ECAM notification. Just ignore it no need to open cross bleed.

Goldenrivett
29th Jun 2017, 11:42
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
30th Jun 2017, 03:36
nice explanation!

Thanks.

Rocket3837
8th Jul 2017, 18:13
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
8th Jul 2017, 21:56
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
9th Jul 2017, 06:30
Rocket3837

You've lost me.

IFLY_INDIGO
9th Jul 2017, 14:22
is it SIM fault or will it happen in aircraft also in case of a real engine failure?

Goldenrivett
9th Jul 2017, 17:05
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
9th Jul 2017, 17:56
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
10th Jul 2017, 09:16
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
12th Jul 2017, 02:22
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
12th Jul 2017, 06:34
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
12th Jul 2017, 07:41
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
24th Nov 2021, 05:00
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 :ok:

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
24th Nov 2021, 05:30
ECAM doesn't disappear but you clear it after actions are completed. That gets the status page. You can always recall ECAM.

FlightDetent
24th Nov 2021, 05:56
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
25th Nov 2021, 07:24
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
26th Nov 2021, 01:03
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
30th Nov 2021, 15:26
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.

sonicbum
30th Nov 2021, 15:52
But mostly to avoid pointless debriefing moments in case th checker considered it necessary.

Then the (big) problem is with the checker as he/she should only point out what the manufacturer's and/or the operator considers necessary and avoid any personal point of view or "technique" on the matter unless clearly stated that this is "what works best for me" and that's it.
Sorry for the slight drift :)

vilas
30th Nov 2021, 16:43
CrazyStuntPilot

What is latched to fire push button is on status page "if performance permits Cross bleed open". This appears if there's no damage.

CrazyStuntPilot
1st Dec 2021, 03:00
I said latched, not linked. The start valve fault is latched, i.e., does not disappear once triggered in that particular scenario. You are describing something else.

vilas
1st Dec 2021, 05:26
Yes! I am describing something else. That's in addition to your info.

BoeingDriver99
1st Dec 2021, 11:26
Is it latched to the Fire P/B then? Because why does it not latch on the ground when you forget to select the APU bleed on?

Also the prompt to open the X-Bleed doesn’t really know if you have damage or not; it only knows if the Fire P/B has been pushed or not.

Pedantic but this is a pretty esoteric thread but I’m learning a lot

vilas
1st Dec 2021, 11:52
Also the prompt to open the X-Bleed doesn’t really know if you have damage or not; it only knows if the Fire P/B has been pushed or not.
The system doesn't have to know if there is damage or not because once you have pushed fire PB you are not supposed to open the cross bleed. So the line on status doesn't appear.