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Jimmy Hoffa Rocks
19th Feb 2015, 18:50
Does anyone have more info and supplementary info on this OEB and other incidents. via links?

It appears that the Lufhansa pilots had previous info on this, good for them.



¨When Alpha Prot is activated due to blocked AOA probes, the flight control laws order a continuous nose down pitch rate that, in a worst case scenario, cannot be stopped with backward sidestick inputs, even in the full backward position. If the Mach number increases during a nose down order, the AOA value of the Alpha Prot will continue to decrease. As a result, the flight control laws will continue to order a nose down pitch rate, even if the speed is above minimum selectable speed, known as VLS.¨

This condition, if not corrected, could result in loss of control of the airplane

¨A Lufthansa Airbus A321-200, registration D-AIDP performing flight LH-1829 from Bilbao,SP (Spain) to Munich (Germany) with 109 people on board, was climbing through FL310 out of Bilbao about 15 minutes into the flight at 07:03Z, when the aircraft on autopilot unexpectedly lowered the nose and entered a descent reaching 4000 fpm rate of descent. The flight crew was able to stop the descent at FL270 and continued the flight at FL270, later climbing to FL280, and landed safely in Munich about 110 minutes after the occurrence.¨

CONF iture
19th Feb 2015, 21:43
DEC 2012 ... 2 years earlier :
http://www.pprune.org/tech-log/502079-a330-a340-ead-aoa-probes.html

vilas
20th Feb 2015, 04:44
Jimmy Hoffa Rocks
AOA information is used by FAC to calculate the protection speeds like alpha prot and alpha max( actually it is AOA shown as speed). These are high AOA protections basically meant to take care of pilot induced low speed situation. Since the normal operating AOA is much lower at higher Mach/speed, the threshold at which the alpha prot is triggered is also lowered. It is something like from 13 degrees to 5 degrees. When AOA sensors are stuck at low speed(high AOA) as the speed increases alpha prot gets triggered since AOA as received by FAC is above the high speed threshold. In this case the displayed alpha prot and alpha max will also be unduly high and incorrect. Alpha prot condition is a latching condition and will cause nose down elevator as long as speed is below this false Valpha prot. This protection can only be overridden when out of normal law. Hence the switching of two ADRs to get into alternate law. A simple solution can be not have this protection in cruise where its utility is minimal as it should be possible for a professional pilot to recover from stall without ground contact(or is it?)

stilton
20th Feb 2015, 08:10
Remind me to never get on an Airbus again :eek:


How many accidents / incidents have to happen before they admit you can't 'pilot proof' an aircraft ?

Magnus456
20th Feb 2015, 12:45
Just wanted to add something to the discussion...

Turning two ADRs would force the a/c into alternate law, as would turning the two FACs off.

Considering it is the FACs that determine the speed protections surely it would be more sensible to turn these off rather than the ADRs and leave yourself with only one reference for airspeed info.

With the FACs turned off you would only lose your high and low speed protections which is a better place to be in than losing your actual airspeed? Of course you would lose yaw damping etc. but I would still consider this to be better than losing two air data units.

Please correct me if I am wrong :)

Cheers.

vilas
20th Feb 2015, 13:09
Magnus456
With AOA problem your actual speed displays are not affected. That data comes from Pitot static and is correctly displayed from the remaining ADR.

CONF iture
20th Feb 2015, 13:51
Magnus456,
I believe the idea was to put in place a procedure as simple as possible, finding 2 ADR switches on a single panel is maybe more practical than looking for specific switches on 2 different panels.
Of course the ideal would be to have a well identified single switch to simply kill the protections ... but is Airbus 'ready' to take that path ... !?

Clandestino
20th Feb 2015, 15:01
Was somebody playing with pressure washer again?

Considering it is the FACs that determine the speed protections surely it would be more sensible to turn these off rather than the ADRs and leave yourself with only one reference for airspeed info.

Blocked AoA vanes is extremely rare situation which can nevertheless have severe effect on any FBW Airbus so it makes sense to have single procedure across the fleet, especially for CCQ flyers. True that FACs OFF (by pbs) is one way to degrade minibus into altn but they are not installed on widebodies and 2 ADR OFF will get rid of protections on any FBW Airbus. BTW, there will be two references left, the other being standby.

Magnus456
20th Feb 2015, 15:56
Was somebody playing with pressure washer again?

Come again?

vilas
20th Feb 2015, 16:27
Magnus456
That is what caused water ingress in AOA sensors which froze after take off, setting a chain of events leading to Perpignan crash.

Magnus456
20th Feb 2015, 17:10
Ah I see. Thanks a lot.

Forgive the ignorance.

Microburst2002
20th Feb 2015, 19:37
Considering it is the FACs that determine the speed protections surely it would be more sensible to turn these off rather than the ADRs and leave yourself with only one reference for airspeed info.


I think the FACs compute the protection speeds for display, only. It is the ELAC that computes those for the protection activation. Still, FACs OFF would bring us to ALTN, which indeed would solve the problem.

vilas
21st Feb 2015, 02:01
MB
FAC calculates but does not activate protections ELACs do.

Microburst2002
21st Feb 2015, 10:49
True, the ELAC gets the info from the FACs, then it triggers the activation, thanks

vodmor
21st Feb 2015, 12:09
FCOM DSC-22-40-10 When a FAC is disengaged (FAC pushbutton set off) but still valid, the flight envelope function of the FAC remains active.

So I'm not sure if switching FACs off would really solve the problem, as long as the aircraft thinks they provide valid data.

vilas
21st Feb 2015, 13:18
vodmor
You have a valid point. There are twenty two different ways to can get into alternate law. Each may have its own handicap. Switching ADRs may be simpler, less complicated and common to both A320/A330. So that must be the reason AB chose it.

clunckdriver
21st Feb 2015, 14:11
As one of the early Bus Pilots in North America I just cant belive that these totally stupid systems have not been removed from Airbus products by now! When we first put crews through training on this aircraft {320s} it became obvious that there were so many problems caused by the totally flawed design concept that we were convinced that Airbus would wake up and fix things, but no, their only reaction was to mumble about "uneducated Canadians" and the merits of everthing French, now the launch customer for whom I worked at the time has given up on them and is disposing of the total Airbus fleet and switching to Boeing, long overdue Im afraid. In the mean time Mr Ziegler and his cohorts push their heads deeper in the sand, combine this with pilots with no real flying background and we will continue to spend time sonar searching the floors of the worlds oceans! {By the way, in case one blames my rant on any anti French bias, I live in French speaking Canada by choice and educated my kids in the French school system}

vilas
21st Feb 2015, 16:01
clunckdriver
Whether anti French or Airbus you are entitled to your opinion. Only thing is North American opinion is not shared by rest of the world. You can see the order book for yourself. In rest of the world where aviation is expanding Airbus proving quiet popular. Is any airline buying any aircraft in Canada at the moment?

clunckdriver
21st Feb 2015, 16:26
Villas, these are not just an opinion, they are the result of dealing with a flawed design concept from day one, indeed the reaction of the Airbus staff we were dealing with at the time of the Air India "Alpha Floor" crash was simply, and I quote," The Indians are just not able to manage modern machinery", ignoring the fact that India has a huge aviation history along with turning out some of the worlds very best computer geeks and engineers, if Airbus had simply stated in training and manuals that having one F/D of and one on would inhibit Alpha Floor, {it was neither taught or in the manuals at this time} this crash would simply not have taken place.As for orders in Canada, yes, West Jet, Air Canada and a new Start Up have large orders placed with Boeing, as for the C Series, time will tell, but right now its way over budget and late, no doubt the Canadian taxpayer will pick up the tab again! By the way, I fail to see the conection between order books and design flaws, the "Bean Counters" have little or no concept of anything other than counting the beans, but that a whole other subject!

vilas
21st Feb 2015, 16:55
clunckdriver
I have gone through the original inquiry report of then Indian Airlines crash and airbus design has nothing to do with it. Brand new machine, unlimited visibility and comfortable morning flight.It is a mirror reflection of SFO B777 crash. In IA crash pilots switched to open descent without realising it and speed kept dropping finally 27 Kts. below Vapp. One pilot switched off his FD without other pilots knowledge. All the time they thought they are in speed mode but no one checked the FMA, there was not a single call about speed by any of them. Finally alpha floor did kick in and also pilots themselves moved to TOGA but they lost their lives because they did it 15 seconds too late. SFO B777 Auto throttle was in thrust hold both experienced pilots never checked their speed and despite much touted moving thrust levers of Boeing they didn't notice that thrust levers were stuck at idle all along, again no call out about speed, speed went 30 kts below Vapp. They also went round but little too late and were lucky to survive. I am sorry but you don't fly approaches like that. Protections are needed for these pilots only. Most pilots won't even experience them in their life time.

clunckdriver
21st Feb 2015, 17:11
This does not change the fact that at this time there was no warning of the ramifications of only one F/D being on when in this configuration, at the time of this crash those of us on the type were in fact interviewd by the BOE, As for the SFO crash, words fail me,the fundementals of aircraft handling are simply not being taught in many places, no amount of "magic" can solve this, certainly more "gongs and whistles" have not proved to be the answer.

Clandestino
21st Feb 2015, 18:44
FCOM DSC-22-40-10 When a FAC is disengaged (FAC pushbutton set off) but still valid, the flight envelope function of the FAC remains active.Keyword might be "a".

As mucking with FACs to degrade control law is beyond the scope of line operations, FCOM can't be used as reference to what would happen. If the operator chooses to include handling in degraded laws in post-heavy-maintenance flight tests, which computers to shutoff, how, when and with what precautions will be included in test schedule. Absolutely nothing from it is allowed to be used in line flying.

This does not change the fact ...that only one FD was active yet alpha floor activated at 135 ft RA, too late to prevent the impact so your statement:

if Airbus had simply stated in training and manuals that having one F/D of and one on would inhibit Alpha Floor, {it was neither taught or in the manuals at this time} this crash would simply not have taken place....is quite false. Since you insist you are early bus pilot in America and so should be very well versed in Airbus, could you please explain us your misunderstanding of Airbus autoflight fundamentals? Or for that matter, fundamentals of any modern AFCS at all?

clunckdriver
21st Feb 2015, 19:20
Clandestino, there were many changes to software to rectify this and other problems problems I think you will find, however although an engineer ,I havnt flown the "Skud" for at least twenty six years,[ could be longer, but my training files are not something I keep handy these days!} so forgive me if I dont recall the endless manual updates which made reporting for duty such a new experience every time, as for your out of place comments about my ability to understand "fundementals" I can only presume that you are some joy to fly with! Please try to reign in your ego and lighten up.{PS, I see you state that I am American, actually Canada is not American, well not yet anyway!}

vilas
22nd Feb 2015, 07:18
clunckdriver
Your statements below show you are not sure whose side you are on. You wrongly blame deactivated protection(because it wasn't) in one statement while in the other you are against the modern preventive innovations. FDs had nothing to do with alpha floor. FDs when both are off ATHR changes to speed mode and that would have taken care off their inadvertent entry in OP DES . B777 A/throttle is worse in SFO it quietly went to sleep as per design and suppose to wake up but didn't. FAA has asked them to improve it.
if Airbus had simply stated in training and manuals that having one F/D of and one on would inhibit Alpha Floor, {it was neither taught or in the manuals at this time} this crash would simply not have taken place.
the fundementals of aircraft handling are simply not being taught in many places, no amount of "magic" can solve this, certainly more "gongs and whistles" have not proved to be the answer.
Surely you can't remember everything but you could always take a breather before coming out with a howler like that.

Clandestino
22nd Feb 2015, 07:36
We are not discussing you or me around here.

What we are discussing is your statement where nice description of FLCH trap was made and concrete example of accident due to it given.

Problem is; FLCH trap (inhibition of autothrottle wake-up on B777 with one FD off and other in FLCH) is not applicable to Airbi, not just because there is no FLCH on them but there is no OP DES trap either and there was never one! Fundamental part is that as Indian Airlines was OP DESed into ground, any 747 can be FLCHed or 737 LVL CHGed in the same manner.

BTW, speaking about "fundementals", it's not even full 27 years yet since A320 entered the service. Not to fly it Canada for more than 26 years would be quite a feat.

Do you have anything to add or are we closing this case?

clunckdriver
22nd Feb 2015, 09:15
Yes, you are correct on the start up dates on the 320 in Canada, however as I stated I no longer keep a diary or training files handy,{ have enough to do with the paper work involved in runing our present company,in fact its 0400 hours here right now and am busy aranging our eAPIS for crossing into the USA today, oh how I miss having all this bumph done by dispatch!} As you semm to delight in personel attacks I have to agree with you, lets both simply can it, its a conversation of the deaf.

tubby linton
22nd Feb 2015, 13:46
Do any of the thread contributors have a reference to show how the protections are processed from detection to the final stage of the aircraft applying a correction. The Fcom doesn't explain this very well.

Jimmy Hoffa Rocks
22nd Feb 2015, 16:58
Airbus needs to be more transparent, as they have been obliviously stuff that needs to be out there. ( We are not even getting into the Electrical abnormals with all the modifications that have had to be done, consequences where you can lose all your screens or comms,etc. ) Airbus needs to provide more information to pilots on this stuff, whether it is pretty or not. Airbus the truth comes out in the end. ( In normal ops when you are fatigued the 320 remains a decent safe airplane to fly when you are doing a lot of sectors and tired.)


Also ¨Airbus had simply stated in training and manuals that having one F/D of and one on would inhibit Alpha Floor, {it was neither taught or in the manuals at this time} this crash would simply not have taken place¨

Airbus stated never have on FD and on FD off, but yes should told us more about what they knew.

It´s ironic and a contradiction, to train pilots not to think outside the box.

But pilots have had to go outside the box switching off Two ADRs to get too Alternate law. Look at Lufthansa.

Here we are with people questioning wether FACs or ADRs should be switched off.

It appears that the Alpha Prot OEB is not enough, or is it ?

tubby linton
22nd Feb 2015, 17:52
The OEB is quite explicit regarding the requirement to turn off two ADR. I do agree with you that there needs to be more explanation in the manuals. Today is the anniversay of the first flight twenty eight years ago of the A320 and here we are many years later still questioning many aspects of how it works.

A33Zab
22nd Feb 2015, 18:18
Airbus needs to be more transparent, as they have been obliviously stuff that needs to be out there.


Active Airbii pilots know where to get the stuff...their Flight Technical dept. and at AirbusWorld.

tubby linton
22nd Feb 2015, 18:19
I have been trying to access Airbusworld and my airline will not give me access.

A33Zab
22nd Feb 2015, 19:58
Here we are with people questioning wether FACs or ADRs should be switched off.



Indeed HERE are those people.


But pilots have had to go outside the box switching off Two ADRs to get too Alternate law. Look at Lufthansa.



They just switch off 1 ADR (the outlier but [GOOD] ADR#3 already rejected by EFCS), which took them in ALT law.

I have been trying to access Airbusworld and my airline will not give me access.

That's regrettable but NOT Airbus withholding you the 'stuff'.

CDA
22nd Feb 2015, 22:47
tubby linton
I have been trying to access Airbusworld and my airline will not give me access.

Tubby, if you have any questions on any aspect of operating the Bus just raise them through your Ops Support Group and keep at them until you get a satisfactory response. It is a sad fact that many line guys don't have access to Airbusworld / Flight Operations (or any other domains on that portal) either because they don't know it exists or don't have an inclination to find out or accept a rebuttal from their company when making a request for access or information. It is also disquieting to know that so many people at the sharp end have insufficient knowledge of the machine they operate and the physical environment in which they operate. Don't stand for it - go get the information ! :D

vilas
23rd Feb 2015, 02:37
tubby linton
Previously Airbus had given access to some TRTO instructors to airbussupply but now they have removed that access except their own instructors. All operators have access to airbusworld but it is sad that many are not aware of the wealth of information it has and are simply not interested.

CONF iture
23rd Feb 2015, 13:41
They just switch off 1 ADR (the outlier but [GOOD] ADR#3 already rejected by EFCS), which took them in ALT law.
You seem to have more info than we do ... but it would be another case where the System would be better advising the crew of the suspected rogue data instead of keeping them in the dark ...

LEVEL600
23rd Feb 2015, 14:44
You seem to have more info than we do

Information from presentation:

Abnormal Valpha Prot
In-service event ( A321)
• At FL250, speed became managed at 290kt but the Autopilot (AP) was unable to reach the target speed. Airspeed remained around 250kt.
• At FL 310, during a L/H turn, the crew reported PFD showing Valpha-prot rising upward current airspeed (245kt).
The flight crew manually disconnected the AP
• Alpha protection activated with an order of pitch down
• Aft stick input maintained for 55 min to keep level flight at FL270
• ADR 2 switched off, leading to alternate law
• Remaining of flight performed in alternate law

• During climb, the following AOA values were recorded:
• AOA1 = 4.5° constant value
• AOA 2 = 4.5° constant value
• AOA 3 = normal behaviour
• The Flight Controls computers rejected the AOA n°3 (no cockpit effects)
• When the flight crew disconnected the AP, the Mach was 0.675.
Alpha prot =f(Mach= 0.675)=4.2°
Alpha prot activated with an associated pitch down
• The protection remained active until reversion to alternate law

CONF iture
23rd Feb 2015, 15:07
Thanks for the info.
Aft stick input maintained for 55 min to keep level flight at FL270
What ... ?

(no cockpit effects)
... is my grievance.

vilas
23rd Feb 2015, 15:35
They need to modify the fault accommodation logic by giving information to the crew. That will improve the situation.

A33Zab
23rd Feb 2015, 19:20
Quote:
(no cockpit effects)
... is my grievance.


Not only this one...I'm awaiting any positive remark on Airbus on your behalf.

(no cockpit effects) is not completely true,
- the crew reported PFD showing Valpha-prot rising upward current airspeed (245kt).
and
- INOP SYS: CAT3 DUAL

(no cockpit effects) is related to the EFCS rejection of ADR 3.

55 min with continued SS deflection makes us wonder what and with whom this may have been discussed?
Home base calling TLS during lunch hour?

But anyway, what to announce? when 2 out of 3 supplies equal but erroneous data, the median being at the same value and the 3rd source deviating from it.

ECAM MSG: NAV SOMETHING WRONG ?

CONF iture
23rd Feb 2015, 21:47
- the crew reported PFD showing Valpha-prot rising upward current airspeed (245kt).
Did materialize during a turn due to G increase - not much time to react.
- INOP SYS: CAT3 DUAL
So much stuff can lead to such STS - not really an indication.

But anyway, what to announce? when 2 out of 3 supplies equal but erroneous data, the median being at the same value and the 3rd source deviating from it.
ECAM MSG: NAV SOMETHING WRONG ?
NAV AOA DISCREPANCY could be IMO the most logical and informative option.

tubby linton
23rd Feb 2015, 22:35
in the early model A320s it was not uncommon to see a status message displayed without any associated warning or caution. The message was always Cat 3 dual inop. It took a bit of digging in tne manuals to discover that this related to an ADR disagree. After a few years these messages stopped appearing and. I have not seen one for at least ten years.

vilas
24th Feb 2015, 01:29
tubby linton
It is level 1 caution. It is loss of redundancy or system degradation, only requires crew monitoring. It is a caution message without procedure. It is still the same.

Microburst2002
24th Feb 2015, 06:25
CONF iture

You are totally right!

The system of voting a computer when the other two agree can have potentially lethal results, and therefore it should be indicated to the crew when this happens, so that some procedure allows us to make sure that the voting of a computer is correct. if computers alone cannot do it, get the pilot involved in the process. No reason to keep it "transparent to the pilot".

THe ECAM you suggest should be accompanied by an AOA CHECK PROC APPLY blue line, or something like that.

A33Zab
24th Feb 2015, 07:40
NAV AOA DISCREPANCY

A 'xxx DISCREPANCY' message is used if one display deviates from the other display.
e.g. NAV ATT DISCREPANCY or NAV IAS DISCREPANCY.

Latest standard A330 do have a NAV AOA DISAGREE msg but only if ALL AOA disagrees or
(after EFCS rejection of one) the - Cz estimation - on the other 2 deviates.

Don't know if this also applies to A320 and what 'Cz' estimation here exactly means.

But in this case displays were in agreement as was the value of AOA1 and AOA2 hence messages would not have triggered.

CONF iture
24th Feb 2015, 17:38
Discrepancy, disagreement, ... this is a topic for discussion when time permits but in the middle of the night all a crew wants to know is that something's going on with the AOA data and prepare accordingly before some protection could mess around ...

tubby linton
24th Feb 2015, 19:23
Vilas, it was not a level one. The only message was on status ,and it appeared as an inop.

Lantirn
25th Feb 2015, 09:36
A3Zab,

I think there was in A320 older msn's the NAV AOA DISAGREE msg, but not sure.

Newer versions have the NAV ADR DISAGREE msg which includes speed or alpha disagreement. However I thought that for this msg to come up would require an ADR firstly to have been failed or rejected by ELACs.

As for the DISCREPANCY msges, I am new in the bus, FCOM doesn't clarify this but makes a lot of sense. Do you know the tolerances for the IAS msg between PFD's? Thanks

Microburst2002
25th Feb 2015, 10:10
A330
the NAV ADR DISAGREE (or the NAV AOA DISAGREE depending on the model) caution is necessary when one of the three ADR was already declared faulty or it was switched OFF and there is a disagreement between the two remaining ADRs (or AOAs, depending on the model).

This caution does not protect us from a treacherous failure of two ADRs or AOAs in such a way that their error is coincident and it has the effect of declaring faulty the only healthy ADR. It is a necessary caution, since with only two ADRs there is no possible voting.

What protects us is that, every time an ADR is declared faulty we have to be healthily paranoid and check that it is OK that ADR #x has been correctly rejected (or not). All the more if the reason of the rejection is a disagreement of one versus the other two. That is why I would appreciate to get that information.

Now I think that the best way to give this info could be a extra line below the NAV ADR FAULT caution (something like DUE ADR DISAGREE?) when the reason of rejecting is the result of a voting.

CONF iture
26th Feb 2015, 01:34
In IA crash pilots switched to open descent without realising it and speed kept dropping finally 27 Kts. below Vapp. One pilot switched off his FD without other pilots knowledge. All the time they thought they are in speed mode but no one checked the FMA, there was not a single call about speed by any of them. Finally alpha floor did kick in and also pilots themselves moved to TOGA but they lost their lives because they did it 15 seconds too late.
Actually they were well aware to be in open descent but didn't know how they ended up in such mode they did not desire. Instead of minding the overall situation and mainly the speed they put their energy on finding why they were on that OP DES mode and how they could leave it.
Instead of reverting to the fully manual solution, they were looking for a software solution (is it a consequence of the training where emphasis was probably more on understanding and managing a computerized system ... ?) but could not find it on such short notice for a System that was new for them.
For guys with their experience on HS748 and B737 it is surprising how they simply forgot about checking their speed, or how one can be easily distracted ...

vilas
26th Feb 2015, 13:57
Problem happened below 500ft. They had asked for visual approach how does it matter which aircraft or mode you are in. You just maintain speed and flight path angle and land. SFO and Bangalore both aircraft were flown visually without looking at speed. In SFO the conventional yoke, active feed back, Q feel, moving throttles but when basic norms are ignored or are absent nothing helps.

A33Zab
26th Feb 2015, 18:05
Do you know the tolerances for the IAS msg between PFD's?


IIRC it is 16kt for ?? sec. as detected by PRIM (FCPC) or if 'Pitot-icing' is detected (fast drop of Pt) by FCDC.

Lantirn
27th Feb 2015, 14:02
So the tolerance is the same as the discrepancy msg.
16kts or 0,05mach for 10secs.

Thank you

CONF iture
27th Feb 2015, 16:09
Problem happened below 500ft. They had asked for visual approach how does it matter which aircraft or mode you are in.
It matters so much that they have crashed.
They had no problem managing the basic only 6 months before but suddenly forget about it after acceding to the latest technology. It only tells that something big has been missing during the training for the transition.

Denti
27th Feb 2015, 17:01
Indeed, the golden rules are probably briefly noted, but the real importance of them seems to be usually lost, especially rule 1 and 2. And that is certainly a lack of the right training.

A33Zab
27th Feb 2015, 22:50
@OK465:

Thx for confirmation.

@ CONF iture / Microburst2002:

Discrepancy, disagreement, ... this is a topic for discussion when time permits

We have all the time here....

but in the middle of the night all a crew wants to know is that something's going on with the AOA data and prepare accordingly before some protection could mess around ...


That is why I would appreciate to get that information.


That's exactly what OEB 48(SR)/49(LR) and (previously OEB 45) is all about, Anticipate->Monitor->Prevent and Recover if the first 3 have been missed.

b215
28th Feb 2015, 01:33
Hi tubby,
I still see this in late msn A/C, usually in turbulence status msg shows Cat 3 single only/ inop sys Cat 3 dual. Indeed due to adiru disagreement.

CONF iture
28th Feb 2015, 14:49
That's exactly what OEB 48(SR)/49(LR) and (previously OEB 45) is all about, Anticipate->Monitor->Prevent and Recover if the first 3 have been missed.
As the System already knows something is incorrect with primary data, why shouldn't it simply inform the crew ... ?
Anticipation part done !

... but then you can only publish a red OEB and put everything on the concierge's shoulders ...

vilas
28th Feb 2015, 15:08
The self identified ADR failure cannot be simulated. To give ADR disagree scenario you need to fail one which is indicated to the crew before making other two disagree .

tubby linton
28th Feb 2015, 15:22
Thank you for your post b215. I have only ever seen it in an A320 not in an A321.

vilas
3rd Mar 2015, 03:49
In 16th Operational and Performance Conference Airbus had indicated a change to ECAM alert NAV AOA DISAGREE and in status page they added RISK OF UNDUE STALL WARNING. It was supposed to be effective in FWC H2F5 MOD 37871 date of completion Jun 2009.

dream747
9th Feb 2017, 03:41
In the latest revision of the FCOM, the OEB on the abnormal alpha prot has been removed. Does anyone know if any modifications were done, if not on what basis was it decided that it no longer applies? Can't find any info on this.

PilotJames
9th Feb 2017, 07:39
Any ideas why on one of the three scenarios you can't use the FPV but on the other two you can?

butcher
15th Feb 2017, 14:50
You can use FPV and vertical speed IF ALTITUDE INFO IS RELIABLE. Need to cross check with GPS altitude, as depicted in QRH.

vilas
15th Feb 2017, 16:39
FPA is Vzbi or Baro inertial vertical speed. When the baro part is lost the bird could not be used. But after Modification No.153528 after loss of ADRs the FPA is calculated using hybrid vertical parameters based on GPIRS. The procedure for all ADRs off now is to use FPV is available.

PilotJames
15th Feb 2017, 17:39
If you have a look at the OEB there are three scenarios listed. The first is for a continuous nose down pitch.
One ADR - Keep on
Two ADRs - OFF

But in this scenario it doesn't say to use the FPV.
My guess is that it's a dynamic situation so the FPV might be erroneous in this situation.

vilas
16th Feb 2017, 11:16
PilotJames
This topic was discussed in the following thread:


A320 OEB Blocked AOA probes 25/12/2012

vilas
16th Feb 2017, 16:19
Actually this is only AOA locked without any problem with Pitot Static system. So the speed and bird are not affected. The first scenario is immediate action in case of uncontrolled descent and the remaining two possible displays on the PFD. The bird should be usable for all the situations.
You can see the explanation from below reference:
http://mes-transferts.lescigales.org/A320-Incident%20%20ALPHA%20PROT%20320.pdf

pfvspnf
17th Feb 2017, 12:45
Yes it's not an unreliable airspeed indication.

Bird using IR data, usable but not sure how it will be very helpful.

vilas
17th Feb 2017, 14:15
The aim is to get out of normal law. After that's done when you loose FD, the bird surely is a help to maintain flight path. Also speed indication is correct.

pfvspnf
17th Feb 2017, 15:12
As an amateur as i am, can you explain how the FDs are not reliable in alternate law when the situation is stabilized?

vilas
17th Feb 2017, 15:37
Because this particular OEB says so.
The AP and FDs are lost for remainder of the flight.

Lookleft
17th Feb 2017, 23:25
And you also need to include the Turkish Airlines crash at Amsterdam. I think this statement combine this with pilots with no real flying background and we will continue to spend time sonar searching the floors of the worlds oceans! is closer to the mark regarding recent crashes.

KayPam
17th Feb 2017, 23:48
As one of the early Bus Pilots in North America I just cant belive that these totally stupid systems have not been removed from Airbus products by now! When we first put crews through training on this aircraft {320s} it became obvious that there were so many problems caused by the totally flawed design concept that we were convinced that Airbus would wake up and fix things, but no, their only reaction was to mumble about "uneducated Canadians" and the merits of everthing French, now the launch customer for whom I worked at the time has given up on them and is disposing of the total Airbus fleet and switching to Boeing, long overdue Im afraid. In the mean time Mr Ziegler and his cohorts push their heads deeper in the sand, combine this with pilots with no real flying background and we will continue to spend time sonar searching the floors of the worlds oceans! {By the way, in case one blames my rant on any anti French bias, I live in French speaking Canada by choice and educated my kids in the French school system}
Everybody loves Mr Ziegler :)
https://en.wikipedia.org/wiki/Bernard_Ziegler

vilas
18th Feb 2017, 07:50
KayPam
clunckdriver is a rabid airbus hater who no doubt was an early airbus pilot but who seem to have gone in hibernation since then and after suddenly coming back to life started voicing same prejudices while the rest of the world has moved on. Likes and dislikes are part of human psyche but it should not be completely divorced from reality. The airbus FBW order book as on 31/01/2017 stands at 16268 aircraft. There are hundreds of airlines that operate them and thousands of pilots like them. No one pilot or an airline can claim to be smarter than everybody else. Boeing also has moved on to FBW and they were not at all keen to extend the only non FBW 737 but for South west their biggest customer demanding an immediate equivalent to A320 Neo or else threatening to buy the Neo. Airbus FBW is different but it is here to stay and thriving not just surviving. Outside the US A320 Neo is outselling 737 by a margin. As you may have noticed some PPL/CPL or non airbus pilots use such posts to have pot shots at airbus. Other than that they are a waste of time.

Denti
18th Feb 2017, 13:32
The OEB 48 is cancelled provided that the aircraft is equipped with at least two Thales AoA probes (PN C16291AB or AA with repetitive check of the heating element) and ELAC standard L97+ or higher (A320) or L99 or higher on A319/A321. Sadly the information we got didn't elaborate what was changed on those ELAC versions, just that it solves the problem.

767-300ER
28th Feb 2017, 14:49
Is there any guidance or thoughts on which two ADRs to turn off...ie does it matter which you turn off? Are there any implications which may influence your choice. I have heard some pilots discuss that turning off certain ADRs may require a manual gear extension later on.

pfvspnf
28th Feb 2017, 15:02
Doesnt specify, PF's data should stay on.

tom775257
28th Feb 2017, 15:38
If you turn off 2 ADRs you will lose Flight directors, Autopilot and autothrust.

If you turn off 1&3 you will need to manually extend the gear and will be in direct law for remainder of the flight once gear down, gear will not come up on a go around.

If you have no prior ADR failure turning off 2&3 would surely be a sensible course of action to allow the capt to become PF for the upcoming alternate law raw data man thrust approach to direct law approach, landing and possible go around. Not saying FOs wont be able to, but personally I would prefer to take that on.

Winnerhofer
28th Feb 2017, 21:31
http://www.pprune.org/tech-log/502079-a330-a340-ead-aoa-probes.html