A 320 Engine Shut Down
 

In the Engine Shut Down checklist of A320 there is a line:
If Wing A/Ice off and Eng fire pb sw not pressed:
If performance permits:
X Bleed open
(If no obstacle constraint exists, open the X Bleed. Can someone please explain what is meant by this.
It also says to determine the single engine gross ceiling, decrease by 1200 ft the result provided by the QRH table. Why should we reduce 1200ft when the single engine gross ceiling is already provided?

Opening the crossbreed will allow both packs to operate. The QRH table would be based on single pack. Therefore a performance penalty applies due to 2 packs.

If you have not had a fire/damage in the failed engine, the ECAM will suggest opening the X-Bleed to provide bleed air to the failed side, to allow use of Wing Anti-Ice.

Also you need that for the engine restart.

What exactly is meant by "If performance permits".

As RUMBEAR said with single bleed two pack operation ceiling is lower. If you can't descend to that because of terrain that means you cannot accept the performance with two pack ops. That's what it means.

Where is this information (ceiling with single bleed and two packs) given? Thanks

disregard...

FCOM: ENG 1 (2) Shut Down, and with the "extra info button 1+2 highlighted,"

"If WING A/ICE off and ENG 1(2) FIRE pb-sw not pressed:
IF PERF PERMITS:
X BLEED OPEN
If no obstacle constraint exists, open the XBLEED, and decrease the single engine gross ceiling by 1200 ft (Refer to QRH/PER-E Ceilings)."

Goldenrivett, the information you provided is in the beginning of the thread.
My question is this:
Where does it say that the ceiling has to be reduced by 1200 ft when the ceiling is anyway given for single engine. As some posts here suggests, if the ceiling is reduced by 1200 feet because a single bleed is supplying two packs, I would like to know where it says that the ceiling reduces by 1200ft when a single bleed supplies two packs.

Boyington, what is it you don't understand by "open the XBLEED, and decrease the single engine gross ceiling by 1200 ft (Refer to QRH/PER-E Ceilings)?"

Goldenrivett, my doubt is this:
FCOM States "To determine the single engine gross ceiling, decrease by 1200 ft the result provided by the QRH table".
This gives the impression (at least to me) that what is given in the QRH is the ceiling for twin engine and we need to decrease 1200ft to determine the single engine ceiling, whereas what is given in the QRH is the single engine ceiling.
And the corrections given at the bottom of the chart is for Anti Ice On whereas the checklist in the FCOM states with a precondition (Black Dot)"If Wing A/Ice off ...."

Maybe I am not seeing something which is very obvious. Can someone please clarify.

If the FCOM was written like this, would that help?

"To determine the single engine gross ceiling with XBLEED open, decrease by 1200 ft the result provided by the QRH table (which is based on XBLEED closed)."

Thanks. It is clear now. Thanks everyone.

Boyington,

Thanks. I think I can see what you are missing.

1) Title of page = One Engine Out.

2)It sounds like you have never opened the X Bleed valve in the sim with Eng Fail No Damage.
If X Bleed is opened, then ECAM asks you to turn on the 2nd Pack. Thus the running engine is supplying 2 packs. The QRH Ceiling graph "One Engine Out" assumes only 1 pack.

Thanks Goldenrivett,
I had seen the Title of the page (One engine Out). What I did not know was that it assumes only 1 Pack. Thanks again for clarifying.