Difference between Airbus and Boeing controls

[DozyWannabe]

CONF iture:

Did Airbus sack you or something? Do something nasty to a family member or pet?

Not meaning to sound rude, but you've just laboured the same three or four points over and over again every single time you've posted on this thread. Yes, some pilots feel the same way as you do and because of that they prefer the Boeing layout - but that doesn't make it objectively safer or better.

Finally, Habsheim was a long time ago, and since then both Airbus and pilots have learned a lot about accommodating each other's viewpionts. The final say on that one was that Airbus were naive, but the fundamental cause was that Asseline screwed up. No more, no less. It astonishes me how many still want to drag that incident up, when the rest of the world moved on over a decade ago.

[Dream Land]

How can you be that sure !?
Do you use something I am not aware of ???

I guess it all comes with the job, as a check airman I was in more of a proactive posture during the landing phase, how do I know what inputs, it's called many flight hours in many airplanes, I am not an above average pilot, every single day in many parts of the world there are hundreds of captains prepared to step in and take control if the landing is being mishandled, all without a yoke . Hint: when the nose goes up, it's an up input, get it, not too tuff if you have any time in an airplane.

[Possum 15]

Either you take control early in the approach as you are the one ultimately in charge for the vessel
- Either you let it go to your limit before you hit the red button, but if you’re low over the ground, you do it because you’ve already decided it was for the go-around

The first option sounds good to me. If the conditions are not suitable for the experience level of the trainee or co-pilot, and/or beyond the company limits (if any) for co-pilot then is there a problem with taking over, or taking the whole sector? On both Boeing and Airbus - NO!
The second option you put forward requires some clarification. Firstly, I would hope "your limit" is within those defined by SOPs. At any time an aircraft unsafe state appears likely or develops you must take over and correct (remember threat and error management?) . Once again, Airbus or Boeing - just do it. There is no question of robbing anyone of anything, safety is the goal of both pilots, not their egos.
The mention of a pilot "feeling passive" is more a reflection on the pilot than the control system being used. If a co-pilot feels the aircraft is in danger he must communicate this to the Captain. If the communication has no effect then he (or she/he) must do something! Both a column or side-stick is eminently suitable.

[Possum 15]

CONF, There is one factor about your view that linked controls are 100% safe that bothers me. How does a commander (for instance) guarantee that the other pilot will allow corrective action to take place? After all there is no priority button on the 734 (for example) control column is there? What happens if "I HAVE CONTROL" or "TAKING OVER" is not complied with? This could be the case of the junior crew member dealing with a commander who is making an error (The "I will not be humiliated by a go-around, I can salvage this" syndrome), or deliberate violation, or is even incapacitated. You must know that these circumstances have led to accidents/incidents in the past. Perhaps some of these incidents may have had positive outcomes if a priority system had been available. Get my drift?

[DesiPilot]

Oh Conf,
If I were flying with you I guess reaching 1000' AGL I will hand over the controls to you knowing that you do not trust anyone sitting on the right seat and you will take over the controls eventually. I would be interested to find out how many Jr. FOs in your company actually get disappointed when they find out that you will be flying with them, knowing very well that you will not let them make any mistakes and you will take over the controls and from the flight during landing phase they will learn nada.
We fly 320 family in my company and the worst one of the lot for tail strike 321 as well. The call "Pitch" is called at 7.5 degrees I am sure as a captain sitting on the left seat you can tell without looking at PFD what 5 degrees or 7.5 degrees looks like.
Take over by all means, but at least let the other person learn as well. Your control coloumn theory is great but I have seen some horific landings in the likes of 73, 74, 75 DC9. I think what it takes is getting used to the airplane. I've had quite a few very experienced pilots jump seat with us when I was flying CRJs. On final approach they were all white knuckeled because we had a 2.5-3 degrees nose down attitude. Now that is a flare for you, from 3 degrees nose down to 5 degrees nose up

[stillalbatross]

The difference between the two is that the Airbus camp see what they fly as a design that gets the aircraft from a to b using a design that the Airbus consortium put together. It is the Airbus take on airliner design. The Boeing camp remind me of a bunch of Religious zealots fighting science with the bible. There is apparently no other way of designing an airliner to get from a to b other than what Boeing do, they would lead you to believe. And every time you mention any other version or airliner design that isn't Boeing it's like saying you had problems with the 50000 animals all fitting on a wooden boat..........

That there could be such a religious following for a company who hasn't made anything in airliner design that was evolutionary is remarkable. Prior to 777, I can't think of a manufacturer in any field who has managed to flog an outdated product for as long as Boeing has done with some of it's designs.

Lockheed and Douglas come back, please

[CONF iture]

DW, who is the first one, and by the way single one, to mention Habsheim in this thread ?
My points are quite close to the thread title ... do you mind ?
You don't like my observations, fine ... it's still what I think.

P15, your comments are interesting, and don't get me wrong, I mainly share them, but did I say:
"linked controls are 100% safe"
It is your own interpretation, as my saying is far less ambitious:
For a 2 crew members, fully visible coupled control columns provide much more information than fully invisible independent sidesticks.

How does a commander (for instance) guarantee that the other pilot will allow corrective action to take place?

If guys are starting fighting for controls, i'm afraid we're touching a much bigger issue and I don't think any manufacturer did ever plan anything regarding that issue ... Probably the Chiefpilot will !?
But if your commander feels that much humiliated, what would prevent him to be the last one on red button ... ?

DP, what makes you think I'm a leftseater ?
Did I ever mention that ?
I'm more interested in PF versus PM, 2 crew members working together.

That's the beauty of fully visible coupled control colums: Every single input is known by both, at all time.
PM can monitor more accurately PF performance ... and let him go further ... best way to learn, I agree too !

Another anecdote on takeoff this time:
I call V1
I call Vr
but don't see the usual nose movement ...
so call Vr again (RWY is long today, no big deal)
when at the same time nose pitches up far too quickly
thanks God, PF is as fast to stop that high rate rotation ...

... not elegant ... but tail was saved !

What happened ?
Mistake was mine, gross error in CG calculation, so gross error in trim setting.
So at first Vr call, PF pulled as usual on his sidestick, but without pitchup reaction, he decided to pull maybe too quickly this time ...

Me, as the Pilot MONITORING I was supposed to be, I was aware of NOTHING !!!
I was just a privileged passenger, nothing more.
Thanks to that beautiful Airbus Sidestick Philosophy ...

And if anyone thinking red button is of any use in that situation ... forget about it, except if your name is ... Lucky Luke.

Now, Dream Land, in your quality of check airman, I assume you would have anticipated all that ... Give me your inputs !

Before I go, can anyone, at last, answer that question ?

Originally Posted by GMDS

So again, please, give me any valuable and professional reason as to why the absence of tactile (and I add visual) feedback should increase safety

[TyroPicard]

CONF
Did you look at the Sidestick Position Indicator? That would allow you to monitor exactly what inputs PF was applying at Vr. I do it on every take-off as PM.....
Lucky Luke

[GMDS]

TP: remember JNB ................
A valuable tip: Look at the attitude indicator, the speed and the vertical speed! It's elementary (called flying), but THIS shows whats happening (instrument feedback) and NOT the sidestick indicator. A lot of top AB instructors now admit, that the Maltese cross serves only during controls check on gnd and is not a useful tool as additional feedback for control inputs by the collegue to get airborne.

[Clandestino]

That thingy that shows sidestick position on PFD (and to me it looks more like WW2 Luftwaffe cross than Maltese one) is certainly not an useful tool as additional feedback for control inputs by the collegue once airborne because... it disappears as soon as weight is not on wheels. A lot of top AB instructors certainly know their FCOMs well.

Very good story, CONFiture. Now let's suppose the same too-little-nose-up-trim mistake has happened on aircraft with classic flight controls:

You call V1
You call Vr
You don't see the usual nose movement, but as vigilant PM you see that capt has pulled just the right amount of yoke so chances are you probably do nothing, believing everything will be fine. I mean, you did nothing when you didn't know what the captain control inputs were, why would you do anything now when you see that they're correct?
Captains pulls a little more and as veesquared starts to bite, nose pitches up far too quickly
thanks God, PF is as fast to stop that high rate rotation ...

So what's the relevance of miscalculated CofG to FBW controls?

[GMDS]

Clandestino you are correct, i misspelled, English beeing only my fourth language. Sorry, it's edited. I meant "to get" and wrote "once".
Must have sounded foolish and out of context.
GMDS

[TyroPicard]

GMDS you are correct - thank you - it's just one of the things I look at, not the only one! I was trying to point out to CONF iture that at rotation you can see exactly what input PF has applied if you are monitoring correctly; I still think it is a useful indication, whatever "top AB instructors" might say. It indicates:
Forward sidestick application at start of take-off roll, and reduction to zero by 100 kts.
Erroneous roll demand will be visible, both during take-off roll and at rotation.
Pitch demand at rotation.
TP

[GMDS]

Thought so, TP.
Beeing not so fond of dead sticks, I wanted to back up CONFiture (a little sarcastically i admit...) in underlining that the SS indicator is ONE more value you have to get "intellectually" on a instrument. With a stick/yoke feedback it makes it much easier to monitor the PF, you can scan inside and outside with less values to be interpreted. As we know, intellectual values are processed by our brain in a serial manner, thus one by one and slower, absorbing more brain power. In these short and intense moments (T/O, LDG), I very much prefer the aid of the tactile feedbacks, because our brain can process these in a parallel way to intellectual values, therefore beeing much faster.
Thats the whole point of my criticism of dead controls. If guys can interpret instrument values as fast and precisely as i did the mix with tactile feedbacks, then they have my admiration and i would accept their standpoint. (I doubt it though, assuming their brain, allthough maybe better equipped, is probably similarly wired as mine.)
GMDS

[Possum 15]

GMDS, are you referring to tactile feedback as PF or PNF? As PF feedback is a non-sequiter, after all you are providing inputs to an hydraulic or mechanical system (in the case of non-FBW) or a FCC in the case of FBW. Any "feedback" is only control system resistance. If you are an IP or a PNF monitoring a manoeuver then how do you get tactile (ie perceived by touch) feedback unless you have your hands on the control column and are inducing the input yourself. You can perceive column position by visual cue, or physically if you have your hands on the column, but not tactile feedback. Not much different to a Bus SPI. Anyway, I will withdraw to my position of saying that I have experience of both systems (except Boeing FBW) and that after a short period to adapt (either way) the same basic principles of aeronautics apply. As someone else observed, it is possible we are missing out on the best system because of the fact that airliner design is now in the hands of two large concerns that are often hindered by their own history. For instance, I always preferred the DC9 to the 727. "Tactile feedback" through that trim wheel I found a little overwhelming (being similar to a pulley wheel on a steam driven farm implement), compared to the trim position indicator. But these days no more Douglas, Fokker, Lockheed etc. What might have been!
Also:

One very fundamental characteristic of the information processing system requires mention. Although man has a vast capacity for sensing information, the decision making stage of the process consists of just one single channel. In other words, although information may be sensed from the approach lights, the altimeter, airspeed indicator and ATC, the decision-making channel is being time-shared between the different inputs.
(Broadbent, 1958; Poulten, 1971)

- So, while one piece of information is being processed, the others are shunted temporarily into the notoriously unreliable short-term memory store to await available time in the single channel. When time becomes available, they are retrieved from storage and despatched on their way. Many factors affect the efficiency of this storage and retrieval operation and a source of potential error is revealed. While it is often felt that one can do more than one thing at time, this subjective feeling results from the rapid scanning and time-sharing which takes place between one piece of information and another.
GMDS, you are a very rare person indeed if you can process through parallel channels!

[GMDS]

Possum.
I don't know if were talking the exact same subject.
Look at your quote precisely. It mentions information beeing put in via eye and ear sensors only. I agree with that processing. However i truly believe that the sensing through hands and the lower end of the spine gets to our brain on a seperate channel, therefore increases the feedback possibiliy.
If your point of view was absolute, then we could give Lewis Hamilton a steering wheel with no street and wheelforce-feedback and simply by watching his instruments and the track he should set the same laptimes. I wonder how he would feel about that .....

I did my share of instructing and felt it easier to evaluate and help a candidate with a moving yoke. Someone mentioned above that instruction was not high on the agenda with the AB philosophy. Lets face it, a huge chunk of our daily ops consists of instructing. As i recall the Israelis changed the design of their Lavi, initially based on the F16 FBW SS, to a moving stick precisely because they said that 30% of its operation was instruction.

Again, the AB system is just as safe as others. A control system that gives you tactile/motion feedback gives you a additional means of feedback and control, beeing as safe as the other.
Why deprive us of such a feature?
GMDS

[Possum 15]

GMDS, greetings, you make some interesting observations.
However, I must comment on your reference to the Israeli military. Don’t be fooled. Like the military of many countries they often do not make the correct choices when it comes to flying training. Take my own country. Despite having quite a good home and away record on the field (except for some unacountably disappointing performances in last centuries major matches), they have made some abysmal choices in both flying training equipment and methods. “All through Jet” or ab-initio on piston/turbine, high performance or not, civilian contractors maybe, tandem seating or not, the list of choices chopped and changed is endless. This has normally been due to “committee think” or just plain incompetence. Sometimes though other factors have played a part; think Bofors, or the number of very recently retired senior officers now taking pay packets from companies they have dealt with while serving! These mistakes are normally rectified with public funds. Good old foul ups in this area in the airline industry are normally caused by short-sightedness induced by the growing influence of bean-counters over operational advice. Except in the case of state-run airlines these mistakes, in the long term, are rectified, if the airline is still alive, with losses to shareholders.
As for your assertion that you can process more than one channel of information (visual, aural or sensory) at a time – I will have to take your word for it that you are different. In over twenty years of reading Human Factors/CRM texts I have never found anything to suggest that the rest of us can. This is the cause of information overload. Information overload can often lead to the shutting down of the decision making process or of “fixation”. Why do so many of our simulator transition courses start with fixed base, “motion off”? Why are some manoeuvres easier to fly motion off? Reduced tactile feedback perhaps? Of course tactile feedback, in the real world, is all too much with us so it has to a part of the simulator training environment – and ultimately it is. Why don’t we perform at optimum in a noisy environment, or if aural warnings are not appropriately silenced, or airframe vibration is severe? I would suggest our inability to, or difficulty in, separating and selecting sensory inputs as we would like to, that is in a logical and correct priority.
Tactile feedback can often be counter-intuitive. How so, you may ask? Take the good old basic steep turn training sequence. Good for scan development, or practice. Disengage A/P and go manual thrust, roll into the turn and at around 25° of bank increase pitch and add a couple of points of EPR or N1. You are then, at 45° of bank pulling like hell to maintain attitude. Of course you could trim, but this leads to problems with ballooning on the roll out, unless of course you trim out of the turn – mmmmm, “flying with trim” – not good! Why not develop a system that allows you to set attitude, add thrust and not have to have the arms of a Bulgarian weight lifter (no offence offered) and the scan rate of Chuck Yeager? WAIT A MINUTE, somebody already did!
Once again, you still haven’t told me how you get tactile feedback without hands on the controls, a very disturbing condition for most students, and even more so for fully qualified co-pilots. It often leads to the “F*** it, he can fly it” attitude, or at the very least an inhibition of natural reaction and input. Of course, this is distinct from the “follow me through” instructional technique which can be useful.
I ran a simulator session only yesterday, with circuit training and engine-out work as the main focus. With this discussion in mind I tried to analyse what were the cues I was really using to determine performance; the most critical area being from V1 to early climb, that is rotation rate and pitch attitude control, yaw control and roll control. I found observation of yoke position (yes I do fly Boeing), either from the instructor’s station or the left seat (student in the right) was not an issue. Performance cues were sufficient. However tactile feedback was important in one particular area. This was rudder input. It is much easier to analyse and teach if the feet are monitoring rudder pedal input. Any instability in roll control can be identified as overactive, or incorrect, use of rudder, thus producing yaw, then inducing roll, as the cause of poor roll control rather than incorrect aileron use. As I am sure you know, poor roll control at this stage makes for poor pitch (and thus IAS) control, as dealing with the roll situation as well as maintaining a constant and correct rate of rotation in spite of the confusing tactile feedback from the control column (change of force versus pitch rate in the 10°NU area), is not easy until learned. From the instructors station it is possible to observe rudder input from leg movement, or readout from screen displayed parameters, but much easier from rudder movement tactile feedback. But, wait a minute! Even the Great Satan Airbus has live and linked rudder pedal movement!
Anyway I feel I am preaching to the already converted, and not necessarily of my faith! I hope I haven’t bored you to tears, or death. Good luck and many happy landings!

[GMDS]

Well, Possum I generally do have my hands on the controls once dirty, and very fast enroute with any little bang or yaw. On the B I instantly know about input and thrust, on the AB I need to look at the instruments additionally.
But you didn't bore me with your contribution, you sometimes almost made my case though ....... so we're not that far apart.
Happy flying on a Boeing, you lucky guy .
GMDS

[CONF iture]

Very good story, CONFiture. Now let's suppose the same too-little-nose-up-trim mistake has happened on aircraft with classic flight controls

1- That was not just "too-little" but MAJOR ... passing 50 feet the VISIBLE trim wheel (and at least it's a good thing they kept it !) moved from 1.5 to ... 4.5 UP
2- No interest in classic flight controls comparison, but in fully visible coupled flight controls, it could be as well 777 or C-17 or EMB last generation ...

So what's the relevance of miscalculated CofG to FBW controls?

I don't know, it is your own question !?
Please do not change my meaning at your own convenience.

You don't see the usual nose movement, but as vigilant PM you SEE that capt has pulled just the right amount of yoke

That's the word I like, so instead of logically thinking that the guy did not pull, you already know he DID, so he's not the one at stake, but airplane is !

so chances are you probably do nothing

WRONG !
I'm already THINKING ... and in the RIGHT direction:
Either that elevator is not connected ...
Either the trim setting is not correct (and I would not mind that option ...)

I am in the knowledge
I am in the loop
I am aware of
I am a step ahead
I am prepared for the probable next development

If it does not make a difference to you, it does a MAJOR one to me.

Captains pulls a little more and as veesquared starts to bite, nose pitches up far too quickly

Wrong again !
If the guy pulls a little more, an additional 15 KT to Vr won't make a huge difference to the rotation rate.
It will if the guy decides to pull too quickly ...
... but if he does it's natural and easy to block it.

Interesting matter:
Due to the sidestick size, it is by far easier to command an abrupt and out of proportion displacement than it is with a control column.

thanks God, PF is as fast to stop that high rate rotation ...

It does not hurt if PNF is in the loop ... two brains usually produce a better fix than one.

Did you look at the Sidestick Position Indicator? That would allow you to monitor exactly what inputs PF was applying at Vr. I do it on every take-off as PM.....
Lucky Luke

No, I did not ... and you're right: I probably should have !
To be honest, it is not something that has been mentioned during initial or recurrent, or I don’t remember, but for sure it has not been emphasized.
Even Airbus keeps very discreet on the subject:

Originally Posted by Note from FCTM

the cross is not to be used by PF during the takeoff, whereas the PNF can check the validity of the PF initial stick input

That's the single mention I've found, and I believe it to be pretty new in FCTM
AI even does not mention it in the « AVOIDING TAILSTRIKES » FCOM BULLETIN where they talk at large on rotation technique.
That makes me think that Airbus does not want to promote the idea that input monitoring must be necessary or at least desirable as they're unable to provide it except for this flight phase ...
Saying that, staring at that little cross during that intense flight phase makes one more too many things to look at and probably extra concentration witch could be detrimental to other parameter observations ... when control column displacements provide such information in a very natural way.

Additional note from Emirates incident safety recommendations :

It is recommended that the operator immediately issue a clear instruction to ensure that the Airbus FBW pilots are left in no doubt that the Side Stick Order Indicator is not to be used for reference during the takeoff rotation

But still, I take your advise Lucky Luke, and I will work on that !
One last thing: Interesting to see that you value and care about control inputs from your team mate, contrary to many here !?

P15, once again I mainly share your comments.

Why not develop a system that allows you to set attitude, add thrust and not have to have the arms of a Bulgarian weight lifter (no offence offered) and the scan rate of Chuck Yeager? WAIT A MINUTE, somebody already did!

No doubt, nice feature, and I would not criticize.
But of any utility during short final ?
My critics go to the way Airbus decided to implement a sidestick philosophy, which is detrimental to a two crew members awareness on each other control inputs, fact Airbus had to acknowledge later on, but for which a fix is "operationally not beneficial, technically not efficient"

From the instructors station it is possible to observe rudder input from leg movement, or readout from screen displayed parameters, but much easier from rudder movement tactile feedback. But, wait a minute! Even the Great Satan Airbus has live and linked rudder pedal movement!

Glad they kept that as well, and did not reach the extreme to do without.
Rudder input consciousness during V1 cut is paramount for PNF.
But do not under value pitch and roll input knowledge (as well as rudder ...) during short final and flare in adverse conditions !

No official jet instruction under my belt, but first months operation with new guys on type requires fair amount of monitoring, and contrary to what was said earlier, simulator is not the place you assimilate everything.

Cessna instruction, so many touch and go, at all time flight control displacements in your visual perimeter, ideal to produce a valuable debriefing, and when requested, discreet hand and feet on these flight controls, in a damping mode, enough to better appreciate student inputs and react when necessary.

... why should it be different on big jets ?

[747dieseldude]

Hi Again.

From reading the posts till now, I learn a few things.
First, this has gone from the old Airbus-v-Boeing thread to a discussion about static side-stick and throttles vs. conservative interlinked moving controls, in terms or cross-checking and monitoring capability.
CONF, and others like us who oppose the still sidestick do not oppose Airbus, or FBW, and not even the sidestick, but only the STILLness of it, and the throttles.

By reading the "pro-airbus" or "pro sidestick" posts, I can learn that airbus has managed to achieve an acceptable (at least by some) system of monitoring other pilot's input. They had done so by introducing new instruments (either 'maltese' or 'luftwaffe' cross) and new procedures ("monitor the cross, but do not use it for rotation" or "if you are clairvoyant enought to know you will need to disengage the a/t, do it above 1,000'....").

According to the posts in this thread, the still sidestick and a/t may provide the same level of cross-checking and monitoring as conventional controls. fine.
But on one, NOT A SINGLE POST, has made a point on how they might be BETTER!?! Isn't new technology supposed to be better? If it can match the old technology only by adding instruments and procedurs, isn't it actually worse?

Don't get me wrong. I thing FBW technology is the way forward, and brings safety and performance.
And the sidestick is good as well, especially during meal service, and during these moments in cruise when you feel you need to stare at the bottom of the HSI.

If only it would move when my buddy or the a/p was doing something, and if only the engine power would match the thrust lever position...

[GMDS]

Amen to every word, Dieseldude.
The constant reduction to beeing a "Airbus enemy" if one criticises the slightest little thing on a AB, sounds Bush-phobic.
Me too wouldn't mind keeping sidestick with the table and even the sometimes woefully confusing ECAM, if only the controls would mirror my collegues or the autopilots inputs.
And it would be SO easy and cheap to add, a lot to gain and nothing to lose but some French pride.
GMDS