A320:Unreliable Airspeed

[Learningtofly85]

In unreliable airspeed the FCTM states:ONE ADR OUTPUT IS ERRONEOUS AND THE TWO REMAINING ARE CORRECT :The ELACs and the FAC and/or FMGC eliminate the erroneous ADR.There is no cockpit effect (no caution, normal operation is continued), except that one display is wrong and the autoland capability is downgraded to CAT 3 SINGLE.

Suppose ADR 1 is erroneous.My PFD will show me the wrong airspeed.Will I not get any indication of the IAS discrepancy ?

[Bus Driver Man]

The NAV ADR 1 FAULT should trigger and will ask you to:
AIR DATA SWTG........................................................ ......................................................CAPT 3
ADR 1 P/B........................................................... ............................................................ .......OFF

If not, use the QRH ADR CHECK PROC which refers to UNRELIABLE SPEED INDICATION and subsequent AFFECTED ADR IDENTIFICATION.

[Fursty Ferret]

Suppose ADR 1 is erroneous.My PFD will show me the wrong airspeed.Will I not get any indication of the IAS discrepancy ?

Speaking from memory here but if the faulty ADR is detected by the aircraft it's more likely the speed tape will be removed from your PFD entirely and replaced with a red SPD flag.

[Learningtofly85]

The FCTM states that :There is no cockpit effect (no caution, normal operation is continued), except that one display is wrong and the autoland capability is downgraded to CAT 3 SINGLE.
And also it says:However, there may be cases where an airspeed and/or altitude output is erroneous, while the ADRs do not detect it as erroneous.

Therefore the confusion 😕

[WhatShortage]

If two ADRs are erroneous but giving the same indication, there won't be any caution for except for the faulty and also correct ADR. That's the scenario you weren't thinking about. Hope it helps!

[First.officer]

As this topic has come up.....would like to query as to what you would do in the following;

Just after becoming airborne (after T/O), CM1 position as PF.....CM1 loses PFD indications (air data, not ATT). Transfers control to CM2 as PF (below thrust reduction altitude), PFD 2 indications appear normal. What would you do, bearing in mind of course "If the safe conduct of the flight is impacted", or not perhaps?.

I'm deliberately not stating what I would do, so as not to cloud any responses - hopefully makes sense? this is just mere curiosity and obviously I adhere to my company's training and procedures.

[vilas]

As CM1 PF when you loose speed indication you are not sure of PM's situation, so just handing over may complicate matters. So just announce loss of speed and go for memory item TOGA, 15° pitch. That's all is there. Then check speed with standby ASI and PM. If OK hand over and use transfer switch and recover. If PM also problem with speed then level off at MSA and apply UAS procedure.

[First.officer]

Thanks for the reply Vilas, makes absolute sense as you describe it - quick question if I may? assuming that the CM2 position has control after the scenario as described (even though not as you would do, obviously) - what would you expect the CM2 position to do ideally? if indications look normal on PFD2, just fly the aircraft (No AP, FD or A/THR, ALT Law) - or would you prefer application of the "Unreliable Airspeed" procedure? I appreciate there is a lot more to consider, this is just in general.

[FlightDetent]

A little assesment is prudent, and prescribed before any action. Especially non-recoverable items, worse yet if from memory.

If you lose the air data, there is no neeed to change the pitch or thrust. Hitting a bird or a stupid insect at liftoff, - as long that you know that the speed is good but not what exactly - do nothing and survive. Hitting toga and going 15° will make the suituation three times more complex.

You need to do what needs to be done, and no more. In the correct sequence, at measured pace. Preferrably watching out one for another. You will find that spirit more developed in the FCTM. What it reads on unreliable airspeed also provides guidance to your questoin.

On a first iteration, I could well argue that handing over immediately is far better choice than actioning memory items . Argue with FCTM paragraps in one hand, A.N.C. in the other.

FCMT PR-AEP-NAV "P" - How to apply this procedure, and even more specifically the three ident Note just above it. As ever, the most importnant facts are in the notes box.

Punchlines for this case study:

Crew coordination is important. The PM should confirm any discrepancy:
If safety of flight path is not affected, the memory items are skipped and not to be done.

[vilas]

For any problem first thing is to FLY i.e. keep control of the aircraft. What I suggested is no different than any takeoff except TOGA part. So just doing it by pitch rather than FD how will it create problems is not understood. Normally the PF will announce the problem shift the reference to ISIS and then check with PM if his side is OK then hand over. But UAS doesn't have standard format it comes in many forms. That's why any speed problem is UAS unless it is not. If you hand over to PM and his side is also affected and his speed is increasing he will intuitively raise the pitch and get in trouble. In simulator such situation pilots have stalled the aircraft. As a principle handing over should only happen after confirmation that his side is Ok. Another failure is IR disagree. You get CHECK ATT flag which is in faded pink that is hardly noticeable. The PF side may be OK and PM side may be faulty. If you hand over without checking he could cause an upset and may invert the aircraft. PF looses his speed at or after rotation he just flies the pitch(at takeoff it's value is known), announces, tells PM to check with ISIS. If OK hands over and uses transfer to recover his own speed. CRM, crew coordination everything covered. It can't get any simpler.

[First.officer]

Thanks for the replies to my question, all very helpful and food for thought. The scenario I have described was one which (admittedly I handled atrociously on the day) still causes me to question to this day the various entries in both FCTM and FCOM. I think it may be safe to assume that I am mis-interpreting/reading what is stated, as statements in (for example) the FCTM-PR-AEP-NAV-"UNRELIABLE SPEED INDICATION" QRH PROCEDURE suggests among other entries "When one indication differs from the others, the flight crew may be tempted to reject the outlier information. However, they should be aware that two or even all three ADRs can provide identical but erroneous data." I also perhaps was recalling an Airbus Safety First publication (05 - December 2007) that stated as a conclusion entry (6): "An unreliable speed situation may be difficult to identify, due to the multiple scenarios that can lead to it. Therefore, training is a key element: indeed the flight crew’s ability to rapidly detect the abnormal situation, and to correctly handle it, is crucial. In case of any doubt, the pilot should apply the pitch/thrust memory items, and then refer to the QRH to safely fly the aircraft, and to positively determine the faulty source(s) before eliminating it (them)." - and also (4.1); "If the safe conduct of the flight is affected, the flight crew applies the memory items: these allow “safe flight conditions” to be rapidly established in all flight phases (take-off, climb, cruise) and aircraft configurations (weight and slats/flaps). The memory items apply more particularly when a failure appears just after take-off." - for clarity, on the day I think its obvious to say that I had doubts, but even so it seems apparent I/we did the wrong thing.

On the day in question, as the CM2 position, I was handed control after take-off and (I think now obvious that this was a mistake) after a look across the cockpit (CM1 PFD, CM2 PFD, ISIS) and with crew co-ordination/agreement (albeit in hindsight probably nowhere near enough CRM!), I called "Unreliable Airspeed" and then went TOGA/15. I made an absolute mess of it! so that confirms that in absence of anything else, I did the wrong thing - overthinking at the time of what is written in the manuals? i.e. the bolded statement earlier on was in my minds eye - as also my thinking was that - "well, the CM1 PFD (air data) has failed/flagged" , "the ISIS airspeed looks a little odd" , "mine (CM2) does look okay". I then thought "what if mine looks okay, but is erroneous", and then "what is the safest option?". Below THR RED/ACC ALT, I did as previously stated. And yes, it was a much higher workload as a result!. There is of course the attendant CRM and crew-coordination that was happening, although maybe not clear in the narrative that I have stated, and either way my performance on the day was very poor.

As it turned out afterwards, this was a simulated bird strike and ADR 1+3 FAULT.

[sonicbum]

Hi First.officer

You got some very valid points from vilas and flightdetent. Now who is right ? The answer is : both !
As You can see to come up with their answers they have thought about their pilot core competencies, and how they would apply them in a real scenario. Remember that "modern" aviation training is getting away from the single solution scenario where we train pilots to react only in a specific way for each specific scenario as real life shows us that events happen in so many different forms and with so many different shapes. Every time You go flying or go to the sim, you bring your pilot's case, and this case is your toolbox, full of competencies that you have developed over time. In this scenario You might decide to pull-out some memory items (application of knowledge) and adapt them to the unclear situation that is developing (situation awareness) or you might decide to initially leave things as they are, the plane was flying perfectly till 1 second prior to the failure with current pitch and thrust, so chances are it will continue to do so for a little while. Now the reason I believe You ended up with a reduced safety margin (when You say that it's been a mess) is about HOW you applied the memory items. the UAS memory items and the subsequent procedure are designed to keep you safe in those kind of contexts, potentially even if there is no failure whatsoever but You have lost situation awareness. So bottom line is the answer to the question "what is the safest option" will be : it depends !
UAS procedure can very well be the answer if applied correctly. Don't touch anything and see what happens during the next few seconds (maybe we get a "ding" from the ECAM with ADR 1 or 3 fault ?) can also be the solution. There is no such thing as one size fits all in our racket and a very successful outcome can be achieved taking completely different paths.

[pineteam]

the flight crew may be tempted to reject the outlier information. However, they should be aware that two or even all three ADRs can provide identical but erroneous data."T.

Not really. It's impossible in real life to have 2 or more ADR providing identical erroneous data. That's why Airbus does not recommend to train that scenario in simulator sessions.

The Adverse Effects of Unrealistic Simulator Scenarios | Safety First (airbus.com) (https://safetyfirst.airbus.com/the-adverse-effects-of-unrealistic-simulator-scenarios/)

[First.officer]

Again, thanks for taking the time to answer the questions I have stated, much appreciated. I think this may well be my interpretations - a little too literally on occasion. It's borne from trying to remove what I perceive as ambiguity in any given scenario and the various training manual resources, and come up with a safe answer. It also begs the question to me personally as to whether really to perhaps re-assess my chosen career-path, as I get older and as the years drift by I'm most certainly becoming 'dumber'! and that's not a good thing on a flight deck....

[Out Of Here]

First Officer : Don’t beat yourself up. I certainly felt I was getting ‘dumber’ as I became older, however I believe the experience gained from age offset the ‘dumbness’ to a certain extent. When I self analysed myself I also came to the conclusion I was attempting to understand finer and finer nuances of the operation this effectively being a result of understanding more than I realised due to said experience. The mere fact you are asking these questions is a healthy indicator and I for one have enjoyed and learnt from this thread. Alas I have witnessed a minority of people in the career who do not think things through and when things get difficult are unable to see the wood for the trees.

[Denti]

The NAV ADR 1 FAULT should trigger and will ask you to:
AIR DATA SWTG........................................................ ......................................................CAPT 3
ADR 1 P/B........................................................... ............................................................ .......OFF

If not, use the QRH ADR CHECK PROC which refers to UNRELIABLE SPEED INDICATION and subsequent AFFECTED ADR IDENTIFICATION.

That should happen. However, ECAM procedures obviously do have some issues at times. Had an IR/ADR 2 fault during line flying once. ECAM only indicated an ADR 2 fault without the action line telling us to switch ADR 2 off. It just told us to switch air data to FO 3, nothing more. ECAM actions complete there was still no map indication, no ADI indication for the FO, just altitude and speed, although the altitude swung around by roughly 300ft at first and finally stayed roughly 100ft higher than the other two altimeters.

[Uplinker]

@First Officer, don't be too hard on yourself. They don't let us take the aircraft home, so it is difficult to practise things such as memory drills in the actual cockpit. And memory drills need to be regularly physically practised to keep the neural pathways open in the brain. Musicians can practise their scales or the piece they are working on at home in their own time, but we have to do it in our armchair without the cockpit around us.

I asked if I could use the cardboard bomber that a previous company had to practise my drills in my own time after hours, but they refused me permission.

So we are limited to using a small cockpit poster, or doing touch drills in the cruise - neither of which are very satisfactory.

If it was up to me I would have pilots practising all the memory drills several times each at every SIM visit.

[vilas]

Not really. It's impossible in real life to have 2 or more ADR providing identical erroneous data. That's why Airbus does not recommend to train that scenario in simulator sessions.

The Adverse Effects of Unrealistic Simulator Scenarios | Safety First (airbus.com) (https://safetyfirst.airbus.com/the-adverse-effects-of-unrealistic-simulator-scenarios/)
What first officer has stated is from FCTM. Unrealistic scenario in the simulator is a different aspect. FCTM cannot be ignored.

[pineteam]

Hi Vilas,
I saw that in FCTM. I think they just wrote that for us pilots to understand the consequences. That article from Airbus clearly states it can never happen in real life. I believe so far it has been the case.

[First.officer]

That article from Airbus clearly states it can never happen in real life

Sadly, I wish I could believe that and whilst I'm sure that it's highly remote in the extreme - it could happen and these things always find a way when all the "swiss cheese holes" align. And if it's possible to replicate in a simulator, then in theory there is obviously thinking that it's a valid training scenario and that has value however remote - or else it has no value and presence in a training programme I would suggest?.

I know from earlier training received elsewhere, it was always a case of "sitting on your hands" initially and paramount to not necessarily believe everything that is presented as true but perhaps only part of the whole picture....and later, use that thinking with your CRM as a crew to also look for reasons why what you believe has happened, maybe hasn't or is partially correct - does anyone else recall that?. It made sense to me at the time as that way you look for other extenuating factors to make sure you have identified the problem correctly and the action(s) taken are sensible and correct to effect a safe outcome as best can be obtained. Rightly, or wrongly (other than my dire performance) I felt that applying the unreliable airspeed memory items at that point could be no worse than just observing and applying ANC (as I had doubts about my PFD necessarily being correct) and validating that my PFD (ADR2) was indeed correct. It does make life damned hard, I will admit - an early level-off and the pitch-power couple etc., is extremely de-stabilising and increases workload hugely and could be considered an invalid response in the scenario as run. But in theory, it keeps within the FCTM and FCOM guidance if an element of doubt exists?. For me personally, if there is doubt then there is uncertainty, if there is uncertainty then the outcome is not assured and you have to make the best decision available to you at the time and that time allows. I felt that to be the TOGA/15 option - I/we was/were wrong.

Uplinker - yes, very good points - I keep thinking that maybe I should invest in some extra simulator sessions to attempt to address these issues, as a visit to the sim every 6-months (excluding pandemic induced delays) is in my case not leaving me feeling overly confident in my abilities (I also always stress prior to sims and adrenaline always makes it doubly hard). And that may be more to my thinking with regard to my future as an airline pilot as I get older. Overthinking it? quite likely - but we are who we are ;-). I also find the FCOM a terrible read, less so the FCTM - which doesn't help and I find at times lacks the details you need, or to find the answer requires hours spent hunting over various areas and keyword searches, to eventually illicit the answer your seeking - if your lucky. It's UI isn't the best and very easy to get caught out if you forget to set the "Layer" visibility as well - but I digress.

[vilas]

Let's get to present case. Let's say both capt and copilot Pitot inlets blocked(not total dual Pitot block which the article forbids) Even this will give wrong airspeed both side. How does handing over help? Instead after takeoff you just fly 15° pitch is it some complicated procedure? Then after checking the third i.e. ISIS for confirmation If PF uses transfer isn't it safer? How can you transfer without ensuring the PM has speed. What safety first says is not to use Dual total Pitot blockage that includes drain holes.

[pineteam]

Don’t over think it. At low altitude follow the memory items if you can’t figure out what IAS Is correct or not sure what is the pitch and thrust setting required at that instance to keep a safe flight path and in the cruise, rule of thumb: Pitch 2 degrees up and 80 % N1 or whatever cruise power was set if you have thrust locked and you will be fine. :)

[First.officer]

Thanks vilas, pineteam....overthinking tends to be an issue for me for sure! and what we did was at low altitude, and was the memory items for unreliable airspeed (albeit badly executed by me!) due to doubt as to PFD (CM2) reliability. And then level-off and verify (using eQRH) as the plan to confirm the serviceability/reliability of my PFD airspeed (i.e. if pitch and power matches approx., then reasonably assured that it's working and reliable in absence of anything else). Perhaps I need to memorise some pitch/power settings as a back-up? although I'm not a fan of such things because of the possibility of mis-remembering and inducing errors where there were none ;-).

[pineteam]

I would not recommend to try memorize them. Make sure you know your memory items by heart. The one in cruise 2 degrees up and 80% n1 is important to know. You don’t want to go 5 degrees up and climb power at high altitude... At lower altitude in clean configuration pitch 2 degrees up and 60% N1 you will be safe too. With experience if you pay attention to the pitch and thrust setting during flights you will have an idea. Sometimes I play a game in my head and try to guess what will be the pitch and N1% when I level off. Saying that, all you have to do really is to follow the memory items if required or just maintained the same pitch and thrust setting at the time of the failure and ask the PM to give you the pitch and N1 setting. I know by looking at the QRH procedure it looks overwhelming but it’s not that bad really.

[FlightDetent]

What first officer has stated is from FCTM. Unrealistic scenario in the simulator is a different aspect. FCTM cannot be ignored.Exactly my point. Both the blue graphics and the text say to apply the memory items only in case safety of the flightpath is affected. At least that's my interpretation of it.

To apply memory items of UAS when uncertain is a valid and necessary correct step for complex scenarios where the indications make little to no sense. In the realm of what actually might happen that is
- radome destruction
- insect infested/blocked pitots
- protective covers left on
- purposely created unrealistic SIM scenario of another freak type (the real existence of unrealistic scenario)

On other occasions there will be some good indication the crew could work with. Applying TOGA+15 indiscriminately and reactively, without trying to assess the situation first and trying to make sense of it, is actually plain wrong. And the book confirms that in writing.

Problem with TOGA + 15 is the performance, ATC liaison and altitude control. Not to sidetrack too much, we all know that dual engine GA are an identified weak spot of pilot performance worldwide - the reasons and effects are of the same ilk here, in my opinion. Also, simulator experience shows that. Rubbing more salt, us busting 600 m without a clearance, UAS or not, would had put my employer in a bad position and myself plus the crew grounded with no pay and possibly demoted.

Most of the times it is possible to tackle a problem from more angles then just one. For the record, I am speaking of correct angles, not pilot creativity. For obvious reasons yet the FCTM provides only one solution, which is an optimized compromise and covers the widest variance of the underlying problems and most conservative way of handling them. The FCTM has been fine tuned to near perfection over the years and the magnificent effort Airbus puts to the multitude pilot and operator conferences. As a matter of fact, the solutions provided within are to be considered obligatory unless clearly not applicable. That is not the case of ADR1 fault resulting from a bird strike destruction of the onside sensors. One could argue that it is the baseline air data trouble and if the FCTM was to cover only one particular case this would be it.
​
Slower is better than quick, coordinated with colleague is better than impulsive. Given the description provided, the OP is correct to seek improving his performance the next time.

First.officer Realistic and slightly under-excited, ever doubting, view of one's own performance is one of the finest qualities in a pilot. You may well be in the correct job, although not the optimum chair yet.

Imagine if this was a real estate agents forum, we would be discussing how best to conceal problems on a property ery and modern trends to hype the customer.

Piloting gives you the chance to be proud and rewarded for doing the correct and truthful thing. That is not at all commonplace!

[vilas]

On other occasions there will be some good indication the crew could work with. Applying TOGA+15 indiscriminately and reactively, without trying to assess the situation first and trying to make sense of it, is actually plain wrong. And the book confirms that in writing. Problem with TOGA + 15 is the performance, ATC liaison and altitude control. Not to sidetrack too much, we all know that dual engine GA are an identified weak spot of pilot performance worldwide - the reasons and effects are of the same ilk here, in my opinion. Also, simulator experience shows that
When close to ground when your FD could be wrong is not a situation that affects flight path? UAS is May Day. We are not going round where there's large flight path and thrust change, we are airborne and climbing may be with TOGA, we just want to ensure that without the possible misguidense by FD. Keeping FLEX is not a problem but following FD could be dangerous.

[FlightDetent]

Neither of us explicitly said so yet, it occurs to me now that we both are indeed pushing for the same thing: Steady pitch! Without it, the safe flight path will be compromised.

You say TOGA + 15 always assures a safe pitch.
I say a safe pitch is already there, just start off with not changing it before jumping forward unnecessarily.

Both correct in its own right and complementing one another.

Following the flight-directors somewhere is definitely lethally undesirable and while they'd be removed for many cases anyway, for a good number of others they are not. When I said do nothing it for sure is not following wayward FDs. How different the outcome of AF447 could have been.

Yes, realizing the FD's are misguiding is one of the greatest challenges, naming one reason it requires skill and attention to other instruments engraved in the retinas and the whole industry seem to conclude we can go on without having that. Well, until the day...

That is when TOGA+15 becomes the safeguard of the first choice, I cannot really dispute that. It's great to see people who strive to do better.

Thanks for the inputs and reflections shared, again.

[First.officer]

I think moving forward, I can see that what I/We did on the day in question....was destabilising and unnecessary in the circumstances of what was simulated, albeit I was trying for (what I considered) would be the safest outcome overall. I certainly made the situation worse. I find that the more I read (learn?), the more questions I have in relation to what's written, and what perhaps is not written - this I appreciate is not possible to cover all scenarios and options that may occur, and is where airmanship/ANC and CRM come in to play, and what makes the outcome the best that it can be. Thanks again for all the comments, it's good to read through and learn and see differing viewpoints.

[Sailvi767]

UAS is not a time critical item. Pilots need to assess what the aircraft is doing. A modern cockpit gives so many ways to do that. You have VSI’s, GPS speed, aircraft attitude, thrust, back up pitot static indications and even ground speed from controllers. Every professional pilot should know the basic attitude/power for the normal flight regimes. You can’t go very far wrong if power and attitude are correct for a given phase of flight. My experience losing airspeed on both sides on a 767 during approach was simple. Maintain 2 degrees nose up and adjust power to maintain the proper VSI and glide slope indications while cross checking GS. It was I admit easier than some situations because we were fully configures and stable at the time. Had we gone around it would have become a much more complicated problem. I recently lost airspeed in a high performance light aircraft without a lot of fancy backups. Managed to center punch what must have been a very large bug and block the pitot completely. Attitude plus power equals performance! Held my normal climb attitude/power until 3000’. Leveled off and drug out my IPad to get a GPS backup for speed and returned to land.

[Learningtofly85]

Thanks everyone for the information.
One more doubt.

In normal operations the airspeed indication on ISIS is supplied by ADR 3?In case of unreliable airspeed ,the cross check with ADR 3 speed is done by directly reading it from ISIS or I have use the switching panel to see ADR3 airspeed on either PFDs?

[FlightDetent]

FCOM-DSC-34-NAV-10-10 "C"
Navigation > ADIRS > Descritpion > Probes Schematic

Again, the NOTE has what you're looking for.

[vilas]

Thanks everyone for the information.
One more doubt.

In normal operations the airspeed indication on ISIS is supplied by ADR 3?In case of unreliable airspeed ,the cross check with ADR 3 speed is done by directly reading it from ISIS or I have use the switching panel to see ADR3 airspeed on either PFDs?
ISIS gets standby Pitot/staic pressure direct without going through ADM. ADR 3 gets also gets through same source but through ADM. You can check even by switching also directly from ISIS.

[Learningtofly85]

ISIS gets standby Pitot/staic pressure direct without going through ADM. ADR 3 gets also gets through same source but through ADM. You can check even by switching also directly from ISIS.
:ok:👍 thank you

[Lantirn]

Have a question and since the subject is relevant, will post it here to not open new thread.

When in takeoff, in a speed discrepancy between PFD1 and PFD2 you apply memo items. When in cruise you dont have to, since the safety of the flight is not impacted. 2,5 and 78 and off you go for the 320.

What is not clear to me is how you handle that when climbing and passing lets say 10.000

Do you still apply memos and then go through QRH? Or do you disconnect FDs/AP and level off with known values that we know from memory (3 and 60 works fine) and then go through QRH?

Have done both in the sim, however I am not sure which is the correct one, but the second seems incorrect to me. Instructor didnt tell me anything about that.

Its a stupid habit I have to avoid overspeed warnings when climbing with blocked pitot tube. I complete the procedure and then climb to avoid all that noise in the sim. But dont think thats correct way

[FlightDetent]

It was on an assesment, when years ago the evaluating pilot briefed this for a mid-way case such as you ask:

6° NU / 60% N1, even on the EPR engines, rule of thumb for level flight. This step is embedded in the QRH tables but it takes some time and effort to read that out.

Even today the tables are not the best design, namely the clean table is organized differently from the S+F one.

In real life, I would not hesitate to use 6/60 to stop climbing if that was needed. The SIM may not be the best place to start showing own memory items.

Airbus procedure covers your dilemma well, as it is. Check the blue diagram for decision making from the FCTM.

= ignore/remove FDs, don't change P+P, pull QRH and 'level off for troubleshooting' using the table.

But it is 6/60.:E
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[Lantirn]

Thanks FD

Was looking at that FCTM page some hours ago.

Haha 6/60 is for GD? Recently I used 4/62 in the sim interpolating from table and worked wonders! 3/60 maybe is for lower altitudes? Have noticed in the actual airplane, but maybe I was fooled, you know sometimes you cant distinguish 3 with 3.5 and if the speed was little higher with lighter GW...idk!

[FlightDetent]

You made me read the books and refresh memory, appreciate the opportunity. :) My previous post is misleading and mistaken to suggest 6/60 gets you level.

The goal is not to skip or replace the QRH table which is used fly level (pretty damned precise). 6/60 will give you a stable and safe trajectory (residual climb) in all cases, irrespective of weight and configuration, engine, winglet and fuselage length, also at different altitudes.

Exactly the case you inquired: Path is safe but you need to act for A.N.C. while the QRH is figuratively out of reach. A procedural gap which 6/60 will bridge gracefully.

LEVEL FLIGHT INITIAL/INTERMEDIATE APPROACH
A320 wingfence CFM engines 60 t (MLW -10%)
clean cf = 5.5 / 54
config 1 = 6.5 / 58
cnf 1+F = 5 / 58
config 2 = 5.5 / 58
L/G + 3 = 7 / 64

LEVEL FLIGHT INITIAL/INTERMEDIATE APPROACH
A320 Sharklet NEO PW engines 60 t (MLW -10%)
clean cf = 5 / 50
config 1 = 6.5 / 52
cnf 1+F = 5 / 50
config 2 = 5.5 / 52
L/G + 3 = 7 / 56

I got advised 9 years ago; for NEO 5.5/55 looks closer to the original concept. But that defies the idea of remembering just one value. I mean, if 6/60 sounds too much with those engines, try zooming on CLB/10 instead.

The 3/60 you mentioned is not good enough with flaps out, resulting in an undesirable combination of sink and acceleration.

[Lantirn]

Nice refresh FD

The 3/60 is a clean airframe value but you are right. Its not enough for dirty config.

6/60 is a very good value to keep in mind and had never thought it like that!

I had in my mind only clean values. 3/60 for low altitudes and 2.5/78 for high alt cruise.

Good to know, thanks!

[pineteam]

NOT to be used a primary reference in emergency, this is just some parameters I observed during flights. Always apply the memory items in case of emergency.

For A320 and A321 in clean config: I have been playing a game in my head to try guessing what will be the N1 and pitch when I level off and after many observations I came with the following rule of thumb:
FL300 and above: Pitch 2 and 80% N1 will keep you out of trouble. Adding 1% N1 for every 3000 feet higher in case of heavy weight could be consider: For instance if you are cruising at FL 360, target an N1 of 82%. On the NEO, I noticed the N1 is usually higher compare to the CEO so I would add maybe 1% N1 every 2000 feet instead.

For lower altitude: Minus 1% of the N1 for every 1000 feet works fine also. For Instance if I was flying at FL 250, I would target a pitch of 2.5 and a N1 of 75% then FL 100 N1 of 60% and pitch of 4 degrees.. The pitch I would increase by 1 degree every 10 000 feet.
These are just approximate values I observed. The one at high altitude is pretty much spot on. You can have a look next time you fly. =)

[vilas]

What is not clear to me is how you handle that when climbing and passing lets say 10.000
Fly 5° pitch, the thrust is in CLB. After that pull out QRH. Take any altitude above MSA and level out using GPS altitude and using the thrust given in QRH. First maintain altitude then check attitude and adjust thrust as required to get correct attitude. No need to tax the memory. Airbus has now come out with Digital Back Up Speed or the D BUS. Now it's ECAM action.

[sonicbum]

Have a question and since the subject is relevant, will post it here to not open new thread.

When in takeoff, in a speed discrepancy between PFD1 and PFD2 you apply memo items. When in cruise you dont have to, since the safety of the flight is not impacted. 2,5 and 78 and off you go for the 320.

What is not clear to me is how you handle that when climbing and passing lets say 10.000

Do you still apply memos and then go through QRH? Or do you disconnect FDs/AP and level off with known values that we know from memory (3 and 60 works fine) and then go through QRH?

Have done both in the sim, however I am not sure which is the correct one, but the second seems incorrect to me. Instructor didnt tell me anything about that.

Its a stupid habit I have to avoid overspeed warnings when climbing with blocked pitot tube. I complete the procedure and then climb to avoid all that noise in the sim. But dont think thats correct way

You apply the memory items when the safe conduct of the flight is impacted as you correctly said. In the scenario you describe you have to mainly assess the MORA, wx conditions (IMC in icing conditions?) and the energy state of the aircraft prior to your acknowledgment of the failure (where you climbing at green dot to make an ATC restriction? Where You at the standard 250/10000ft/econ climb ?). In other words, am I happy with current pitch/thrust with respect to the environment? If the answer is yes, than keep your present parameters and ask for the unreliable speed checklist to level off for trouble shooting and don’t forget to communicate with ATC your situation. You still must disconnect AP/FD/ATHR anyway as you don’t want the automation to start chasing erroneous parameters. Besides that, any harm in having 5 degrees ANU and CL thrust passing 10’000ft (memory items value) ? Your normal climb parameters will be the same in terms of thrust and almost the same in terms of pitch. One thing: don’t level off by memory. It’s a big no-no. If Airbus wanted us to know 6/60 or whatever they would have put it as a memory item as well. Levelling of by memory because you’ve read it works on pprune doesn’t look nice at all. Always use known and official parameters. If the aircraft climbs, then keep climbing, no one has ever hit the sky and the t-cas is there for this reason. Once you have figured out the level-off parameters then apply them.

[pineteam]

Just to be clear: On my previous post I never intend these numbers to be used in an emergency. I did not see the question about unreliable airspeed above FL100 until now. I just wanted to share some fun facts observed while flying. Unreliable Airspeed is a memory items and shall be applied as Sonicbum explained very well. I will edit my last post just in case. xD

[Lantirn]

Nice that the subject got hot.

About the "passing 10000ft unrel speed" case:

Sonicbum and vilas, your posts imply applying the memo items before going to QRH and then ECAM to do the switching or whatever the ECAM is.

What I can understand is, that when on cruise you dont apply if the safety is not affected. When on takeoff its affected, so you apply memo.

In the 10000ft scenario just using a pitch obtained from memo items, without completing the memos seems like an improvisation. And an improvisation can have some of the memos, added actions like "leveling off", switching controls (which is really big no no again if you are not sure from QRH which side is correct) , other personal techniques and then where is that red line? You can have endless personal opinions. From these posts Sonicbum implies AP/FD/ATHR off, while vilas talks about CLB 5. Respect both. Of course its a forum and I know that maybe you didnt explain by detail exactly the steps, but you got my message. Techniques can be endless but airbus procedures are specific. And the airbus procedures werent clear for me for that phase.Thats why I made the question in the beginning.

I have done a level off it in the sim by memory, but in the end I was thinking that that maybe was a bull****. Unluckily my instructor didnt tell me anything.
The reason that I adopted this subconsciously was to avoid the overspeed warning from the erratic block pitot tube during further climb, which gave me the sense of a correct completion of the exercise because the overspeed warning never occured.

Now about the subject of personal pitch and power settings memorization that pilots do, I find it perfectly normal because this is what saves your day in the end. Also your colleague might also give you wrong values from the QRH, which has happened especially with new F/Os. How to use it and when to use it is what we discuss here. I think its a good habit to know soma basic values.

[Goldenrivett]

Nice that the subject got hot.

About the "passing 10000ft unrel speed" case:

I have done a level off it in the sim by memory, but in the end I was thinking that that maybe was a bull****. Unluckily my instructor didnt tell me anything.
The reason that I adopted this subconsciously was to avoid the overspeed warning from the erratic block pitot tube during further climb, which gave me the sense of a correct completion of the exercise because the overspeed warning never occurred.

Hi Lantirn, I believe the overspeed warning in the sim during climb with a totally blocked pitot (that's with both the pitot tube and the drain hole blocked by ice) has produced negative training value. Airbus frowns upon this sort of "training" as it is so unlikely to happen. See Adverse effects of Unrealistic simulator scenarios (https://safetyfirst.airbus.com/the-adverse-effects-of-unrealistic-simulator-scenarios/)

In real life - you should have time to continue the climb with 5° pitch and the thrust set in CLB (as Vilas says) until you get figures from the QRH or you were already in level flight when the problem occurred (as in AF447) then all you had to do was maintain the cruise pitch and cruise power.

[sonicbum]

Nice that the subject got hot.

About the "passing 10000ft unrel speed" case:

Sonicbum and vilas, your posts imply applying the memo items before going to QRH and then ECAM to do the switching or whatever the ECAM is.

What I can understand is, that when on cruise you dont apply if the safety is not affected. When on takeoff its affected, so you apply memo.

In the 10000ft scenario just using a pitch obtained from memo items, without completing the memos seems like an improvisation. And an improvisation can have some of the memos, added actions like "leveling off", switching controls (which is really big no no again if you are not sure from QRH which side is correct) , other personal techniques and then where is that red line? You can have endless personal opinions. From these posts Sonicbum implies AP/FD/ATHR off, while vilas talks about CLB 5. Respect both. Of course its a forum and I know that maybe you didnt explain by detail exactly the steps, but you got my message. Techniques can be endless but airbus procedures are specific. And the airbus procedures werent clear for me for that phase.Thats why I made the question in the beginning.

I have done a level off it in the sim by memory, but in the end I was thinking that that maybe was a bull****. Unluckily my instructor didnt tell me anything.
The reason that I adopted this subconsciously was to avoid the overspeed warning from the erratic block pitot tube during further climb, which gave me the sense of a correct completion of the exercise because the overspeed warning never occured.

Now about the subject of personal pitch and power settings memorization that pilots do, I find it perfectly normal because this is what saves your day in the end. Also your colleague might also give you wrong values from the QRH, which has happened especially with new F/Os. How to use it and when to use it is what we discuss here. I think its a good habit to know soma basic values.

Lantirn,

seems like what you are looking for is a black and white answer on “I have unreliable speed at 10’000ft, what do I do?” And so on like “what about 11000, 12000, etc..”.

Airbus tells You very clearly: if the safe conduct of the flight is impacted then apply the memory items, otherwise applying the memory items is not required. You are a pilot hence you should be able to evaluate (also based on what I have described above) if the safe conduct of the flight is impacted or not, this is the reason we do still have human beings on board the airplanes. So let’s review again your scenario. In case of a partial or total blockage of a pitot tube your airspeed indicator will start over reading during a climb. How bad this is going to be depends upon how badly the pitot is blocked. It is absolutely normal to end up with several nuisances such as the overspeed warning but you don’t care as you know the airspeed is unreliable and all you care about having some parameters that will keep the acft within the envelope, such as the memo items parameters or the parameters you were flying prior to the failure if that is the case. You want to try an interesting failure to demonstrate how the system works? Next time you are in the sim ask the instructor to block the stby pitot and insert icing conditions in IMC. Keep climbing and you will get an ECAM overspeed warning out of nowhere when your PFD 1 and 2 will show normal climbing speeds, say 250 knots. In that case ADR 3 senses an overspeed due to the stby pitot blockage which will also be shown on the stby instruments. So the nuisances warnings are to be disregarded (except the stall warning) just rely on the pitch/thrust parameters. The biggest CRM training element in the unreliable speed scenario is Surprise and Startle especially when the failure doesn’t come as per textbook, and that is exactly what we must focus on as pilots.

[Lantirn]

Yes I am getting your concept how to deal with this philosophy. I should just disregard the overspeed warning and Goldenrivett is right about unrealistic scenarios.

[FlyA32F]

How do you manage your lateral navigation when encountering unreliable speed on take off?

[FlyA32F]

Where do you navigate to in case of unreliable speed after take-off?