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lunarair
24th Jul 2014, 06:17
Single bleed fault ECAM action and PRO ABN do not mention descent but MEL limits ops above FL315. So in case of bleed fault in flt. Would you descent?

Main point is - does MEL still apply after dispatch??

Ollie Onion
24th Jul 2014, 06:57
Well, the MEL does NOT apply after dispatch but you would probably refer to it. A single bleed MEL'd doesn't actually cap the flight level to FL315 unless your speed brakes are also inop. So in other words if you have a single bleed fault after dispatch and your speedbrakes are working then there is no need to descend. If your speedbrakes are inoperative then if you choose to refer to the MEL you might decide to descend to FL315 but are not obligated to.

jaja
24th Jul 2014, 06:57
No the MEL do not apply :

"The provisions of the MEL are applicable until the aircraft commences the flight (the point when the aircraft begins to move under its own power for the purpose of preparing for take-off)."

Edit
Ollie was faster than I :-)
I fully agree with Ollie

fruitloop
24th Jul 2014, 07:31
Am I missing some thing here....How long does it take to get to Fl 100 if the other bleed goes U/S....??

lunarair
24th Jul 2014, 07:34
Oh it might have changed. It used to limit up to FL315.

Allow me to quote another example here:
MEL dispatch with NWS fault will limit t/o and landing to below 20kt XWind. If it happens in the air (i.e. In many major failures!). Does this becomes a limitation? Note that ECAM and PRO-ABN do not mention it at all!

KRviator
24th Jul 2014, 07:41
Am I missing some thing here....How long does it take to get to Fl 100 if the other bleed goes U/S....??Probably the same amount of time in the case of a rapid decompression, though if you dispatch with one bleed inop and your second fails in flight, presumably the outflow valve would close to maintain pressurisation & it would then be a case of how long till the leaks in the airframe allow it to depressurise.

You might even be able to do a relatively normal descent after your second bleed failure if you're having a good day.

yotty
24th Jul 2014, 07:54
What does the QRH say?

Ted Nugent
24th Jul 2014, 09:15
What does the QRH say?

The QRH only references AIR ENG 1+2 BLEED FAULT Descend to FL100 if no bleed recovered, APU bleed from FL200 if avail. Max FL with APU bleed FL200.

Ollie Onion
24th Jul 2014, 09:46
Lunair,

You will find that for a Single Bleed Fault there are now 2 MEL entries, one stipulates NO FL Limitation if Speedbrakes are operative and one stipulates a limit of FL315 if Speedbrakes INOP. All due to the certified time to reach FL100 with and without speedbrakes.

In the case of the MEL limit on NWS, if you have this fault after dispatch there is NO requirement to reference the MEL, so if the 20kt limit is not mentioned on the ECAM / QRH / IFLD etc then it doesn't apply. Of course a prudent pilot would probably have a look at the MEL even after dispatch and may well decide the prudent course of action is to land somewhere with less than 20kts crosswind.

vilas
24th Jul 2014, 14:02
As correctly pointed out MEL is not applicable for the present flight. But in line operations there are two aspects safety and operational. Safety is ensured by ECAM actions but operational aspect may make you consider MEL for diversion etc. if the MEL is going to ground the aircraft for want of maintenance facility. You can consult operations if in contact.

OPEN DES
24th Jul 2014, 16:59
Itīs all about probabilities.
When dispatching with an MEL item you typically have reduced redundancy in a particular system. To take a further and subsequent failure into account the MEL can prescribe a certain limitation to contain that risk.
When something fails in-flight the MEL does not apply as explained very well by some of you. Statistically it is less likely that you suffer a subsequent failure within the same system in-flight, hence this is not taken into account and no limitation applies.
Itīs the same concept with Alert Height. Once below AH a single failure in the aircraft system does not cause a downgrade in the aircraftīs landing capability. The AH in the realm of auto land is analogous to the point where the aircraft starts to move under its own power in the realm of MEL (!)

Vilas has a very good explanation, I would add one important thing:
If I suffer any failure before take-off I will always consider the performance implications and not blindly dismiss the MEL. Any failure affecting the braking/stopping capability of the aircraft has to be addressed! FCOM/ECAM does not address these things. Also in the Airbus in particular you have to be careful that Config 1+F doesnīt become Config 1 due to ADR problems etc....

gAMbl3
24th Jul 2014, 18:51
Doesn't he FL 315 limit apply in case of dispatch with Air Conditioning Pack (one Air-conditioning Pack in heat exchanger cooling mode only) and if the non affected air conditioning pack fails in flight?

Field In Sight
24th Jul 2014, 22:06
Generally the MEL doesn't apply after dispatch, but it does if you have a failure affecting P-RNAV or RVSM.

Regardless of all that, I would still refer to it and probably heed it's warnings.

Flo121142
25th Jul 2014, 02:58
By the way, the Fl limitation for the bleed fault does only apply to some older MSNs. I experienced a single bleed overheat (which could not be reset) recently, we checked our MEL and found that for the MSN we were in there was no Fl restriction if the speed brakes are operative, but on some of our older aircraft to Fl 315 - I don't know why they have a different restriction, maybe it has to do some thing with the engine type (our older aircraft are IAE powered, the newer ones are CFM) or something else, maybe somebody else knows why this is this way...

screwdriver
25th Jul 2014, 07:12
The MEL philosophy is that there will be a further failure. That failure will be the loss of second bleed source or second pack.Due to the leak rate of the airframe , there is an altitude limitation to allow the aircraft to get down before the fuselage loses all pressurisation...I seem to recall!;)

Superpilot
25th Jul 2014, 07:47
This is an OEB on a lot of MSNs.

vilas
25th Jul 2014, 11:28
As long as it is a question of remaining pack/bleed failure it is not that catastrophic as the cabin rate of climb is of the order of 600ft to 800ft per minute. So emergency descent should take you to 10000ft without much problem.

compressor stall
25th Jul 2014, 11:44
This is an OEB on a lot of MSNs.


Yes, it was due to the crossbreed opening after a bleed failure and the remaining good system then overheating.

There is a SB that replaces the Temperature Control Thermostat that solves the problem. :ok:

mr.brembo
2nd Aug 2014, 16:30
I thought, that all operators cariing out flights on airbus 320 have OEB-40. We don't have OEB remainder, but in case of bleed failure we have to rever to QRH, in flight off course.

Cough
4th Aug 2014, 15:37
The latest versions of FWC negate the need for the OEB. So not all but I guess at the moment, most A320 series have OEB 40.

IFixPlanes
6th Aug 2014, 06:42
Restrictions depends on different ECS (pre or post MOD 30626), FWC standard and the aircraft type. Speedbrakes are related to the A319. Without all speedbrakes the AC is not able to get down to FL100 in time when the 2nd pack goes INOP.

rudderrudderrat
6th Aug 2014, 10:47
Speedbrakes are related to the A319
What is so different with your A320s?
Our A320s still require speed brakes to be operative in order to plan FL 370.

IFixPlanes
6th Aug 2014, 13:57
Sorry, i choose my words wrong. Even when speedbrakes are operative the A319 is limited to FL370 with one pack U/S.
Our A320 and A321 can fly up to maximum when speedbrakes are OK.
Check out the MMEL (http://fsims.faa.gov/PICDetail.aspx?docId=M%20A-320%20R25).

compressor stall
21st Aug 2014, 03:58
320:In manual flight: 40d for spoilers 3 & 4, 20d for spoiler 2.

And what are they for the A320 with the Autopilot engaged? How much different are they to those of the A319? :cool:

I don't have an A320 QRH, but I assume AP OFF is not part of the Emergency Descent?

Even when speedbrakes are operative the A319 is limited to FL370 with one pack U/S

That would appear to be the case for the MEL above, but MELs in different parts of the world differ. Not all have FL370 as a limit. It may be exceeded with restrictions.

Citation2
22nd Aug 2014, 12:49
From a legality point of view there is no need to descend , as per the provision of MEL , as long as speed brakes ares operative. Airmanship might dictate otherwise depending on the situation , this is where captain decision comes into play and that's why robots haven't replaced pilots yet.

Similar question just to give food for thought . AC ESS BUS FAULT leads to the deactivation of cabin oxygen masks door ( Auto+manual are inop) and this is not even indicated in ECAM , just a little note on FCOM saying so. So now your pax don't have oxygen in case of depressuraziation.

Would you descent to FL250 ? Considering that your A320 has become an "ATR" , would you continue at FL390 because there is no "if scenarios" ?
Would you ask you your purser to use the Manual Release Tool to open manually all oxygen masks doors in the cabin scaring your pax , or would you stay quite and proceed to your destination?

Metro man
31st Aug 2014, 07:57
If you descend consider the fuel penalty, not the cost but WX at destination, alternates and your minimum divert fuel.

Dan Winterland
2nd Sep 2014, 01:56
Single bleed fault ECAM action and PRO ABN do not mention descent but MEL limits ops above FL315. So in case of bleed fault in flt. Would you descent?


Depends on your aircraft - keep an eye on the cabin alt and diff press. I've had a bleed fail in flight twice above FL315. One time, there was no problem, the other, the cabin alt started creeping up as it was an older aircraft with leaky door seals. We descended.

As in all cases, you need to know the procedures but also have the knowledge to apply them effectively. A bit of airmanship and common sense is always required.