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Airbus takes pilots back to basics with the A350

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Airbus takes pilots back to basics with the A350

Old 9th Oct 2012, 19:58
  #161 (permalink)  
 
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Its not impossible, holding the button can still disconnect the sidestick and the drive mechanism on the other side.

An incapacitated pilot or suicide pilot is no different in terms of locking out from the controls.

But even on todays airbii, the last pilot to push the button will have control of the aircraft. So its not a given that the other pilot can lock out the suicide pilot.
Last pilot to push has priority!

But with todays technique it is possible to design interconnected sidesticks that can be deactivated/segregated in case of failure/ pilot incap/ suicide pilot.

Providing the best of both worlds in terms of tactile feedback on what the autopilot/other pilot is doing, space in the flightdeck and protection against failures/ pilot incap.

The ONLY reason not to do this is weight and development cost. I'm advocating a NEW design which is better in my view.

But since that new design doesn't exist currently I prefer the conventional interconnected system. As I'm more likely to have to prevent a hard landing/overcontrol on a daily basis than having to fight a suicide pilot or deal with an incap.

Last edited by 737Jock; 9th Oct 2012 at 20:11.
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Old 9th Oct 2012, 20:11
  #162 (permalink)  
 
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Originally Posted by 737Jock View Post
Last pilot to push has priority!
No, if held down the button locks out the opposite side for approx. 30 seconds.

Originally Posted by 737Jock View Post
The ONLY reason not to do this is weight and development cost.
Incorrect. In normal airliner operation the only reason for two pilots to be on the PFC is when muscle power is required to give extra leverage in the event of manual reversion. In a fully-hydraulic setup there is no manual reversion and thus no need for both pilots to manipulate the PFCs.

Last edited by DozyWannabe; 9th Oct 2012 at 20:13.
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Old 9th Oct 2012, 20:12
  #163 (permalink)  
 
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Not if the other pilot pushes the button again. A locked out sidestick can be activated inflight by pressing the instinctive disconnect button on the deacivated sidestick.

Additional within those 30 secs the other pilot can press for priority which will switch priority to that sidestick.

But again this is ALL a matter of design, its not impossible to overcome any of this. Your arguments are flawed.

You never had an instructor tell you, put your hands on the control and feel what I'm doing? You never had a captain help you in the flare?
There are various reasons why 2 pilots can be on the controls during normal line operations, not just manual reversion.
On top of that because of interconnectivity the other pilot can see the inputs of the other pilot and give advice or help if neccessary.

Last edited by 737Jock; 9th Oct 2012 at 20:17.
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Old 9th Oct 2012, 20:15
  #164 (permalink)  
 
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Originally Posted by 737Jock View Post
Not if the other pilot pushes the button again. A locked out sidestick can be activated inflight by pressing the instinctive disconnect button on the deacivated sidestick.
My notes say different. A single press can be overcome by pressing the other side, but a lock-out (when the button is held) locks out both the opposite PFC *and* the opposite button.

Originally Posted by 737Jock View Post
You never had an instructor tell you, put your hands on the control and feel what I'm doing? You never had a captain help you in the flare?
First question - this is an airliner, not a trainer. Second - I'm not a line pilot, so no. If you're in the RHS of an airliner you're supposed to know how to do it. Interconnected controls in a trainer are a must, but in an airliner not so much.

On top of that because of interconnectivity the other pilot can see the inputs of the other pilot and give advice or help if neccessary.
The same is possible by looking at the instruments. The truth is that connected controls have made very little difference in emergency situations if looking at it from a factual and historical perspective. In fact, sometimes it can even be a crutch - not to take anything away from the UA232 crew, but they were still forcing the yoke long after it was obvious that it was having no effect.

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Old 9th Oct 2012, 20:21
  #165 (permalink)  
 
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Suggest you correct your notes or start reading the airbus FCOM DSC-27-20-30

Sidestick priority logic
‐ When only one pilot operates the sidestick, it sends his control signals to the computers.
‐ When the pilots move both side stick simultaneously in the same or opposite direction and neither takes priority, the system adds the signals of both pilots algebraically. The total is limited to the signal that would result from the maximum deflection of a single sidestick. Note: In the event of simultaneous input on both sidesticks (2 ° deflection off the neutral position in any direction) the two green SIDE STICK PRIORITY lights on the glareshield come on and “DUAL INPUT” voice message is activated.

A pilot can deactivate the other stick and take full control by pressing and keeping pressed his priority takeover pushbutton. For latching the priority condition, it is recommended to press the takeover push button for more than 40 s.

This allows the pilot to release his takeover push button without losing priority.
However, a pilot can at any time reactivate a deactivated stick by momentarily pressing the takeover push button on either stick.
If both pilots press their takeover pushbuttons, the pilot that presses last gets priority.

Note: If an autopilot is engaged, the first action on a takeover pushbutton disengages it.

In a priority situation
‐ A red light comes on in front of the pilot whose stick is deactivated.
‐ A green light comes on in front of the pilot who has taken control, if the other stick is not in the neutral position (to indicate a potential and unwanted control demand).

Note: If the aircraft is on the ground and commencing its takeoff run and one stick is deactivated, this triggers the takeoff “CONFIG” warning.

Last edited by 737Jock; 9th Oct 2012 at 20:25.
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Old 9th Oct 2012, 20:24
  #166 (permalink)  
 
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OK, so my notes are missing the last part, but the argument that the other pilot does not have to counteract the muscle power on the other side to recover still stands.

(See also: one side jams - the other side is OK)

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Old 9th Oct 2012, 20:31
  #167 (permalink)  
 
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No it doesn't. Technically it is possible to design the system in such a way that the disconnect button deactivates the sidestick and drive system on the other side when pushed and held. Which caters for possible sidestick failures/pilot incap/ pilot suicide.

Again I am advocating a NEW design. And in terms of the current situation I think its is more likely that I will need to save the aircraft from a hard landing/overcontrol than a pilot incap where the incapacitated pilot overpowers me in a struggle for control. So as a line captain I prefer interconnected controls because it gives me an array of options to help the first officer.

The suicide pilot story is completely different and doesn't even apply in the current airbus design, as fighting for control through the priority logic will favour the suicide pilot who wants an unstable flight.

You keep racking up all kinds of scenarios that are ALL less likely than a hard landing through mishandling/not flaring/ flaring too late/ flaring too much/ pilot induced oscilation.

Last edited by 737Jock; 9th Oct 2012 at 20:37.
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Old 9th Oct 2012, 20:41
  #168 (permalink)  
 
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And yet none of these have happened due to lack of interconnected PFCs. There is no conclusive evidence to state that the design is any worse.
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Old 9th Oct 2012, 20:47
  #169 (permalink)  
 
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What does that even mean?

On a weekly basis, flying with 200 hour guys I am left with the question is he/she going to flare? How much is he flaring? Are we going to float?
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Old 9th Oct 2012, 20:49
  #170 (permalink)  
 
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What does that even mean?

On a weekly basis, flying with 200 hour guys I am left with the question is he/she going to flare? How much is he flaring? Are we going to float? Why is his descent rate constantly changing?

In terms of monitoring what the other pilot is doing the current airbus system is worse, in terms of protecting against sidestick faults/ pilot incap the system is a bit better.

But designing a system that caters for both is achievable. Why stick with this old 80's technique?

Not designing a new system is all about weight, money and possibly the old boeing vs airbus war.

Last edited by 737Jock; 9th Oct 2012 at 20:52.
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Old 9th Oct 2012, 20:59
  #171 (permalink)  
 
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Originally Posted by 737Jock View Post
On a weekly basis, flying with 200 hour guys I am left with the question is he/she going to flare? How much is he flaring? Are we going to float? Why is his descent rate constantly changing?
If you don't trust them, then land it yourself. But it's likely that if they are new then they've practiced it several times over more recently than you have. Trust them.

But designing a system that caters for both is achievable. Why stick with this old 80's technique?
Why stick with an old '20s technique that only existed because the cable control system required it?

Not designing a new system is all about weight, money and possibly the old boeing vs airbus war.
Nope. It's about "if it ain't broke, don't fix it" - and the evidence to hand states categorically that it ain't broke!

If it makes you uncomfortable then that's fine and entirely your prerogative - but opinion does not make fact.
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Old 9th Oct 2012, 21:05
  #172 (permalink)  
 
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During 447's wild ride, UP, PNF kept after the PF: "You are going up, so go down." PF said he would, but did not. "J'ai redescends". How was Robert to know the a/c remained uncommanded? He could not know.

That is not CRM, de facto, that is adversarial action. For precious seconds, Robert was compelled to believe in a man who was not delivering Nose Down...

The simple fact remains, for critical seconds, the aircraft was flying SINGLE PILOT......

Then STALL. After STALL, it became academic, almost ironic.

"But I HAVE been pulling back, all the while".... no shit. And people defend this architecture?

Bonin did not have a clue what his controls were doing to the airplane. Because of the design, neither could Robert....

Is there a pilot on deck? What are we missing?
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Old 9th Oct 2012, 21:10
  #173 (permalink)  
 
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What a BS dozywannabe. It has nothing to do with feeling uncomfortable and with about 4 sectors per day I doubt they have had more exposure than me...
You think that I can defend myself in court with, well I needed to trust the guy?

So to be clear what I am saying is that the current airbus system limits MY ability as a captain to monitor what inputs the first officer and even the automatics are making. An interconnected system gives me MORE situational awareness regarding FO input/ automatics input, that is a fact!

Aviation and specifically command is all about situational awareness. To just say trust the guy is the same as saying trust the design. So why worry about failed sidesticks, jammed controls, suicide pilots etc.

Every pilot cocks up a landing now and then, inexperienced guys are statistically more likely to do this. And when they do statistically it will be worse than an experienced guys cock up.

BTW If interconnected systems are from the 20's the adagio "if it ain't broken don't try to fix it" also applied for airbus when they designed the current system in the '80s.

Last edited by 737Jock; 9th Oct 2012 at 21:16.
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Old 9th Oct 2012, 21:15
  #174 (permalink)  
 
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There is no evidence, whatever, that Airbus intended for this controls layout to improve safety, or CRM, oy anything other than weight, and cost, period....

They were looking for three things, Weight saving, cost saving, and something to market as different, only.

Change for change sake, and buzz.
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Old 9th Oct 2012, 21:15
  #175 (permalink)  
 
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Originally Posted by 737Jock View Post
So to be clear what I am saying is that the current airbus system limits MY ability as a captain to monitor what inputs the first officer and even the automatics are making. An interconnected system gives me MORE situational awareness regarding FO input/ automatics input, that is a fact!
Not a great deal more than you can get from reading the instruments though - and you can take that to the bank.

You're a Captain, not an instructor. If you feel unsure of the capabilities of your colleagues in the RHS, then your beef is with your training department, not Airbus.

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Old 9th Oct 2012, 21:19
  #176 (permalink)  
 
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You are clearly not a pilot... and you can take that to the bank...

When I can feel the inputs, I can look outside the window to monitor the landing. In case a correction needs to be made I can help.
Looking at the instruments is TOO SLOW to do that, on the airbus there are only 2 options beside accepting a hard landing. Takeover or go-around.

But let me get this right according to you airbus designs a system that reduces my situational awareness inherently which is OK? And I need to take that up with my training department?

I'm done with your trolling. You don't know your aircraft systems, you get beaten on every single argument you make. This thread is all about designing a new cockpit that is designed around the pilot increasing his SA, and giving the pilot exposure to flying the aircraft instead of punching buttons.

And you stick out your tongue saying stuff like, if it ain't broke don't try to fix it and take it up with your training department.

Aviation is all about safety, and sure you trust other people but that doesn't mean you let them do anything unchecked. Likewise aircraft systems have always been changed/enhanced to provide safety enhancements.

Clearly the current airbus FBW logic has an impact on Situational Awareness. And the biggest impact on safety is Situational Awareness. Period.

Last edited by 737Jock; 9th Oct 2012 at 21:32.
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Old 9th Oct 2012, 21:30
  #177 (permalink)  
 
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Originally Posted by 737Jock View Post
This thread is all about designing a new cockpit that is designed around the pilot increasing his SA.
The A320 flight deck *was* designed with pilot input, and signed off by a group of pilots led by the best the UK had to offer (Capt. Gordon Corps - successor to the legendary Capt. D.P. Davies of HTBJ fame).

Aviation is all about safety, and sure you trust other people but that doesn't mean you let them do anything unchecked.
So check them on the instruments - you don't need connected controls to do so!

Clearly the current airbus FBW logic has an impact on Situational Awareness.
Clearly how? You've shown no proof (and neither has anyone else making the same arguments for the decade I've hung around here...) - just your opinion.

Last edited by DozyWannabe; 9th Oct 2012 at 21:39.
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Old 9th Oct 2012, 21:38
  #178 (permalink)  
 
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That is because you are not a pilot. And there are various opinions on the best what the UK has to offer in the rest of the world so let's not start that discussion.
Anyway it would be a gross misconception to think that those pilots had absolute authority on how the flightdeck and controls were designed. They were working within design constraints.
Most likely the technique of the 80s could not deal with interconnected driven FBW either.

Lets not get started on looking at the instruments 20ft above the runway, its bullshit and can't be anything more than a glance while trying to find a maltese cross that can be anywhere on the PFD depending on the input that is made. You then need to judge if this input is sufficient... Oh boom you hit the runway...

The a320 cockpit is a 1980's design. The world of aviation was very very different. Airline pilots had more hours, more exposure to conventional aircraft. Airtraffic was less dense. There was more manual flying, i itial training took longer etc etc.

There is lots and lots more scientific background on how people process information. There is about 20 years of incident and accident data.

I can see a lot of reasons why the design can be updated into the 21st century.

Last edited by 737Jock; 9th Oct 2012 at 21:49.
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Old 9th Oct 2012, 21:46
  #179 (permalink)  
 
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Originally Posted by 737Jock View Post
That is because you are not a pilot. And there are various opinions on the best what the UK has to offer in the rest of the world so let's not start that discussion.
See above - better than the ARB's chief test pilot?

And I may not be a pilot, but judging by what I've read on here, you do not speak for all pilots - you probably aren't even speaking for a majority.

Lets not get started on looking at the instruments 20ft above the runway
Who said anything about 20ft above the runway? If you're referring to the Lufthansa incident (which has happened precisely *once*), that approach should not have been made in the first place as the crosswind gust limits were exceeded.

The a320 cockpit is a 1980's design. The world of aviation was very very different. Airline pilots had more hours, more exposure to conventional aircraft. Airtraffic was less dense. There was more manual flying, i itial training took longer etc etc.
Really? I'm reading a lot of received wisdom in that paragraph, but little in the way of evidence. Are you saying that cadet programmes did not exist in the '80s? And I don't get what air traffic density has to do with interconnected controls. During line operations, one pilot should be handling the landing - not two.

There is lots and lots more scientific background on how people process information. There is about 20 years of incident and accident data.
All of which (regarding tactile PFCs) is theoretical and none of which has been proven.

I can see a lot of reasons why the design can be updated into the 21st century.
Again - you're assuming that connected controls are objectively better in a majority of scenarios - an assertion which you are free to believe but is nevertheless not supported by the evidence.

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Old 9th Oct 2012, 22:03
  #180 (permalink)  
 
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Yes better then the ARB's test pilot. Again those pilots were working within a set design frame. They did not have absolute say on the cockpit design and controls. Additionally there were technical constraints that will likely have prevented a system of interconnected driven FBW, flight enveloppe protection etc...

Because landing the aircraft has everything to do with getting close to the ground. Is that a surprise to you?
The biggest change in pitch happens during takeoff and landing, which happens to be close to the ground where time is no luxury. The timing and rate of pitch change is very important which is all directly related to the input on the sidestick.
In addition the judgement of when to flare and how much to flare is completely based on outside visual cues. Not instruments!
So to be able to feel the input enables the pilot monitoring to look outside for visual cues and judge if the input is sufficient. This can hardly be achieved by monitoring instruments.

You seem to be very bad in combining various items together. I'm not saying cadet programs did not exist, but they made more hours in flightschool before joining the airline, they spent more time in linetraining, they flew less sectors, there was less time pressure, there were less cadets coming through, experience was much more diverse, etc etc etc.
The world of aviation has changed dramatically compared to the 80's, especially with the rise of lowcost aviation.

And you are assuming that connected controls are worse, which is neither backed up by any evidence. My suggestion is to design a new FBW system that combines the good aspects of both systems together.

But if you ask the moderators to organise a poll on what pilots prefer regarding interconnected sidesticks vs segregated control sidestick we can get some evidence. So a driven interconnected sidestick vs a current airbus sidestick. NOT boeing vs airbus.

Personally I don't know a single pilot in my airline who would prefer the current system with "instinctive" disconnect pushbutton over a system where the sidestick would move. And yes this is a discussion item in simulator excercises and training chats.

But apparently the only proof for you would be a major incident or accident. Any hard landing incident or even a long landing/ soft bounce you will never hear about seems to be of no value to you. You don't seem to know about holes in swiss cheese lining up.

Life is not black and white in aviation as you seem to make it, it is very grey indeed. Maybe that LH airbus should not have started the approach because of crosswind limits, but that doesn't mean that the control system did not have any impact on the incident.

Last edited by 737Jock; 9th Oct 2012 at 22:21.
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