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IFLY_INDIGO
30th Jun 2017, 03:43
In simulator, I have noticed that when an engine fails without any other failure, the ECAM status displays LDG DIST PROC APPLY.

I don't get it. Why landing distance will increase due to engine failure?

compressor stall
30th Jun 2017, 04:35
Have a look at your expanded FCOM ENG 1(2) SHUTDOWN. It only applies if there is severe icing or REV unlocked etc. IIRC there's a blank line in the sim that makes it look like its a new heading, but its still a line item of the white "IF"...

JABBARA
30th Jun 2017, 12:26
Some ground spoilers may not be extending...

Amadis of Gaul
30th Jun 2017, 14:02
Sounds like a good question for your sim instructor, no?

Zaphod Beblebrox
30th Jun 2017, 14:59
At American we have this really slick app on the ipad called "A320 Landing Distance" which has all the approved configurations, select-able weights, runway conditions and wind. There is also a non-normal or "LDG DIST PROC APPLY" which is really quite simple to use as compared to the old method.

It really works well.

tmtxpress
30th Jun 2017, 15:24
On the QRH "Landing Distance with Failure - Engine" tables you will find the two scenarios which require the Landing Distance to be assessed as "with Failure".

lurkio
30th Jun 2017, 15:43
Take the example of an engine fire or damage scenario where the first bottle was fired. Now it is the middle of winter (of course) and you pick up ice which cannot be shed because you cannot use wing anti-ice from one bleed source because the cross bleed must be kept shut. Somewhere in the QRH PER section there is the example of SHUTDOWN with ENG FIRE pushbutton pushed and Ice Accretion. It has a delta ref of 10 so there will be a penalty to LDR.
I am sure my learned colleagues will come up with better examples but I like to keep it simple.

vilas
30th Jun 2017, 15:59
This confusion is created because on status page where it says
1. If fire push button pushed and ice accreation
2. Vls vref+10kts
And after a gap it says
3. Landing dist procedure apply
This gap gives an impression that it is not linked to earlier two conditions. But it is linked to speed increase due to ice accreation. Whenever there is speed increment landing distance increases and it needs to be calculated.

Goldenrivett
30th Jun 2017, 16:14
If landing on a Runway which is not dry, then there is a penalty for any reverse credit which you may have originally assumed.

From QRH Landing Distance without Failure.
Braking action = Poor, each working Thrust Reverser would reduce your landing distance by 300 to 400 m.

sierra_mike
30th Jun 2017, 16:39
quick question regarding the VAPP calculation in case of ENG FAIL with ENG FIRE pb pushed in icing conditions

according QRH VAPP=VREF+deltaVREF+APPR COR
if we assume ATHR OFF and calm winds we would have to correct for ice accretion in the APPR COR.
so do we need to "double-correct" for ice in that case??

old,not bold
30th Jun 2017, 16:48
Why landing distance will increase due to engine failure?

In my tiny and untrained mind I have always thought it's because asymetric power means that not only have you lost 50% of reverse thrust, you may not be able to use all the remaining 50% and stay on the runway.

That's as well as all the clever stuff mentioned already.

rogerg
30th Jun 2017, 17:46
As you usuly land with less flap when on one engine which gives a greater approach speed, maybe thats it?

vilas
30th Jun 2017, 18:45
sierra_mike
Good question! Although in both places the addition is due to icing but 10kts addition with fire push button pushed comes as delta Vref, so strict interpretation should be to add in both places.

lurkio
30th Jun 2017, 19:02
Vilas, yes the "strict interpretation" would have you adding the 5kt APP CORR to the 10 delta Vref. However, the ice is the same ice so the logical thing to do would be to just add the delta Vref 10 kts as it is the greater of the two.
You couldn't be criticised for doing it the way you suggest but if anything else went wrong you probably could be for doing the logical thing.

Another nail in the coffin of airmanship I am afraid.

IFLY_INDIGO
1st Jul 2017, 04:21
This confusion is created because on status page where it says
1. If fire push button pushed and ice accretion
2. Vls vref+10kts
And after a gap it says
3. Landing dist procedure apply
This gap gives an impression that it is not linked to earlier two conditions. But it is linked to speed increase due to ice accreation. Whenever there is speed increment landing distance increases and it needs to be calculated.

Best Answer :ok:!

quick question regarding the VAPP calculation in case of ENG FAIL with ENG FIRE pb pushed in icing conditions

according QRH VAPP=VREF+deltaVREF+APPR COR
if we assume ATHR OFF and calm winds we would have to correct for ice accretion in the APPR COR.
so do we need to "double-correct" for ice in that case??

I would avoid double correction for a single event

Romasik
2nd Jul 2017, 01:48
Have a look at your expanded FCOM ENG 1(2) SHUTDOWN. It only applies if there is severe icing or REV unlocked etc. IIRC there's a blank line in the sim that makes it look like its a new heading, but its still a line item of the white "IF"...
Well, may be 330 is made of different substance, but there is nothing in the Engine Shutdown Procedure about icing...
Anyway, we have to apply Landing Distance Procedure on all landings :). I don't know why there is a reminder...

akindofmagic
2nd Jul 2017, 08:14
As you usuly land with less flap when on one engine which gives a greater approach speed, maybe thats it?

Routinely landing with reduced flap in the OEI case is not explicitly an Airbus procedure unless overweight (although CONF3 is of course a valid option). In any case, as CONF3 is an approved configuration, no landing distance procedure (beyond the notmal requirement to check your landing distance) is required.

Some ground spoilers may not be extending...

Care to elaborate on why you think that may be the case? I assume you're not an Airbus pilot?

Vilas' answer is spot on.