AIRBUS New QRH (2012-RCAM) - ENG Fail (No Damage) LDG Dist calculation

[Hudla]

Hello folks,
has anyone of you idea, why in case of ENG fail (no damage) on A320 family is no applicable matrix/table in new QRH introduced by Airbus in 2012?
I wouldn't wonder until I found out that on A330 there is one. A330 distinguishes two cases: ENG Fail w/o damage and with damage (Fire P/B pressed).

(This question applies to new QRH with extended PERF part including RUNWAY CONDITION MATRIX ASSESSMENT (RCAM).)


Thank you. :ouch:

[Airmann]

Interesting Question. For that matter what exactly constitutes the SHUTDOWN? In parenthesis it says "if ENG FIRE pushbuttom pushed and if Ice accretion" I don't quite get it, does it mean if both the conditions are met or only one? And as Hudla said, why the choice of these failures and not others? Where's the Airbus rep?

[Microburst2002]

My explanation:

in the A330 you have to land in CONF 3 when you have an engine failure. So you have to make a landing distance procedure, only because of that. With flaps 3 you will use more runway. As you know, in the table you have to use flaps full VREF and add any deltaVREF. In this case, deltaVREF when there is an engine flame out is 5 kt, due to the fact that you are actually landing with flaps 3 instead of full. Not for any other reason. Also, you will have a few spoilers less, because the 330 has no PTU. This affects the landing distance factor.

Now, in the 320 you can land with flaps full, so there is no need for any abnormal configuration landing and you have all spoilers so there is no need for landing distance procedure, except if ther is icing conditions and you have isolated the failed engine bleed (XBLEED SHUT) due to an engine damage (every time you push the fire shut off valves out you are "declaring" declaring the engine as damaged and will have the XBLEED SHUT blue line in the ECAM). In that case you cannot use Wing anti ice, because you must not use it in only one wing. Then, because of the icing conditions, you have to calculate increased landing distance and a delta vref to account for the ice accretion.

[Microburst2002]

Nope

But ECAM will tell you to XBLEED OPEN in blue. You can use opposite bleed for packs and for WAI.

A damaged engine bleed has to be isolated as a precaution. If it is engine 1, then you even "lose" APU BLEED, too, because you cannot supply a damaged engine with hot air at high pressure...

[Airmann]

Sorry Microburst I deleted my last post, but you posted before it disappeared. I took a look at the procedure and it made more sense to me.

I am new to the Airbus so forgive me if the question is a little naive, but it seems that after pushing the Fire PB you lose the ability for the opposite eng to supply anything via XBleed. The procedures show that x-bleed should be shut as soon as the Fire PB is pushed? Why is this, is it just the way the air is fed when supplied via the opposite side? I understand that you need to shut off everything that is connected to the damaged engine. But whats stopping the other engine from still supplying bleed air to the wing anti-ice or the pack on the opposite side?

Also, with flap 3 I thought the computer automatically calculated the additional VLS, so the pilot doesn't need to make any changes. If it were the case on the 330 that you needed to add knots due to the flap 3 Config on engine out you would also need to do so during a normal flap 3 landing as well?

[porch monkey]

Designed by morons for genius'

[Hudla]

Gentlemen,
thank you very much. Now it makes sense to me. I have really admiration for Microburst2002 knowledge of Airbuses (not just from this thread)! :ok:

X-Bleed is the answer, what I was looking for and was missing in my puzzle :ugh:

Happy landings!

[Microburst2002]

Hudla, Thank you!

this issue of the landing dist proc of a damaged engine brought a lot of controversy, because it wasn't well expressed in the QRH and many thought that every time you had such failure you had to do a landing dist proc Later on they fixed it and now it is clear that only in case of ice accretion you have to do it. In 320.

Airmann

The bleed from the opposite system will reach not only the users such as WAI or PACKS, but also the faulty engine bleed valves. If there is damage, bleed air could make things worse, maybe leaking into the nacelle and increasing fire risk or who knows what... It seems to me that as a precaution, you have to isolate the affected bleed channel.

In the 330 we will lose either the blue or the yellow hydraulic, because we don't have PTU. This leads to loss of two spoilers per wing, which leads to a landing distance procedure. Once you are there, you have to use CONF FULL vrefs. So they have to add a deltaVRef only to account for the CONF 3 situation. As you say, there is no abnormal configuration, here, and CONF 3 VAPP could be used, imho.

cheers

[Airmann]

OK thanks Microburst. I finally get it.

[BlackandBrown]

If only everyone on pprune was as helpful as microburst2002. Good on you mate and well done for knowing your aircraft so well.:ok:

[Microburst2002]

Any time!
thank you guys for rising my ego. I sort of needed it

cheers

:8

[Airmann]

I know I should just let this thread die at this point but what the hell I have nothing better to do so I'm going to ask another question:

Why does Airbus make us use the Vref figures in the QRH when calculating Vapp rather than allowing the pilot to pull out the Vls figure from the box? One would think that it would be more precise given that it is calculated for the exact weight and CG. That is of course if its available to the pilot, no problem with having a back up chart of course.

[Microburst2002]

It is a backup. You can use MCDU VLS (CONF FULL always) if available.

[Airmann]

Ok thanks Mr. Microburst, if I pass my next check ride it'll be because of you.

[EGPFlyer]

Also, the speeds in the box are for the expected landing weight so make sure your plan is sequenced first if you are diverting and are planning on using the FMGC speeds rather than the QRH.

[Microburst2002]

Yes, and use CONF FULL VLS before switching to CONF 3 in the MCDU pagewhen landing with a delta VRef with CONF 3:

1st. insert the intended FPLN
2nd. See CONF FULL VLS in the MCDU
3rd. Add delta VREF and corrections if applicable
4th. Insert that value in VAPP field
5th. Select CONF 3 in the MCDU

You will also need to select GPWS FLAP 3 mode, in the 320 family.

Good luck in the check!

[320p]

Hello Microburst2002,

What is the significance of the step 5 in your last post i.e "5th. Select CONF 3 in the MCDU"?

Thanks

[Microburst2002]

In the ECAM landing memo you will not have "green" after selecting flaps 3 unless you have selected CONF 3 as the landing configuration in the PERF APPR page, in the MCDU. But don't do it before usin CONF FULL VLS for delta vref computations, hence the order of things.

[OPEN DES]

The GPWS LDG FLAPS 3 p/b is to reconfigure the ECAM LDG memo and the GPWS.
The FLAPS3 selection in the MCDU is just to allow the A/THR to command Vapp iso F-speed when the approach phase is activated.

Best regards

[Microburst2002]

Exactly

In the 330 these functions are mixed. That is a good excuse...:{

[320p]

"The FLAPS3 selection in the MCDU is just to allow the A/THR to command Vapp iso F-speed when the approach phase is activated".

I thought that the Flap selection in the MCDU would only change the VLs in the MCDU,and the A/THR would command the Vapp shown in the MCDU. If so, then my previous question may still hold since in step 4 we have manually inserted the Vapp.:confused:

Thanks

[OPEN DES]

"The FLAPS3 selection in the MCDU is just to allow the A/THR to command Vapp iso F-speed when the approach phase is activated".

I thought that the Flap selection in the MCDU would only change the VLs in the MCDU,and the A/THR would command the Vapp shown in the MCDU. If so, then my previous question may still hold since in step 4 we have manually inserted the Vapp.

Thanks

The Flaps3 selection in the MCDU changes the VLS and the resulting Vapp. However we don´t care about that when applying a Vref increment, as the increment is always based on Vref (Vls CONF FULL).

The reason that we still select Flaps3 in the MCDU even when we have manually inserted a Vapp is due to the autothrust logic.

With the approach-phase activated the speed targets are as follows:
Conf0 - Green Dot
Conf1(+F) - S-speed
Conf2 - F-speed
Conf3 - F-speed *
ConfFull - Vapp target

*When we do a Flaps 3 landing we´d like the A/THR to command Vapp tgt rather than F-speed. In order to make this happen we select Flaps3 in the MCDU even when we have manually inserted a Vapp.

Hope this clears things up.