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AF447 wreckage found

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AF447 wreckage found

Old 16th Aug 2011, 16:57
  #2941 (permalink)  
 
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Originally Posted by GarageYears View Post
Repeat with your left hand...
I tried.
But unfortunately there was a glass of whiskey in the left-hand location.....

Good description, thanks .... and personally I think the 'left/right' discussion is vastly overdone.

Maybe there is a very small part of the population that is really severely "left-hand-challenged".
But if so, would they ever have gotten as far as the RH seat of an AB?
They would have needed to show their competence in a LH seat as well.
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Old 16th Aug 2011, 16:57
  #2942 (permalink)  
 
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feedback with sidestick

What about having a screen or even better a small portion on the HUD (they are introduced slowly) that shows a rectangule divided in 4 quadrants with a dot showing where the stick position is. Add a RH/LH indication for where the input comes from and a 'Dual Input' flashing indication when there is dual input...

Something similar with what fighter aircraft/helicopters have in the targeting pods' screen to show where the sensor is looking compared to foward.

(I'm not a pilot)
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Old 17th Aug 2011, 00:12
  #2943 (permalink)  
BarbiesBoyfriend
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I hope you'll all forgive me for sticking with this angle for a moment.

Would the PNF and Captain have had a better grasp of the situation had they SEEN a yoke held full 'nose up' ie with the PF holding the yoke right back, probably with both hands!?

I think...Yes.

Someone would have said 'push FFS!'

With the sidestick (and I know it works great on single seaters) this was plainly FAR from obvious.


A second point re flying hours. I've seen 20,000 hours as the experience on the FD mentioned a few times. 19,950 of that was prolly playing sudoku (or whatever long haul guys do) while the AP flew and the FMS nav'd.

At my company we have to show one 3degree landing a month (steep apps normal) and there's also recency for Autoland.

Why not recency for visuals and hand flying? Why not for raw data too?

God knows we could all do with it.

These guys were very poorly prepped for their hour. And when the hour arrived............

Automation makes you (and me) lazy.

It's the new killer.
 
Old 17th Aug 2011, 00:23
  #2944 (permalink)  
 
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Now you can argue that the central joystick should be oriented fore-aft/left-right on axis with the aircraft, but now you are inducing a very painful twist to either arm, and the stick movement is no longer in-line with any of the arms natural axis.
Except that your analysis is not borne out in reality...

I have flown several aircraft with central control sticks from Cubs and similar light airplanes to fighter jets. I have also flown the AH-1W Cobra helicopter with a right-side control stick that moved (yes, actually MOVED) in the normal fore-aft and left-right axes. NONE of those were even remotely "painful." All of them fell naturally to hand.

While a ergonomically shaped and positioned stick grip is better than a straight stick like the Cub's, even the straight stick poses no problems for translating the arm/hand's 45 deg orientation to the 90 deg orientation of the control movement. The reason is that the stick is anchored, not free-floating, and the arm/wrist/hand readily adapts to the control movements. The brain has no problem translating.
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Old 17th Aug 2011, 00:27
  #2945 (permalink)  
 
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Originally Posted by BarbiesBoyfriend View Post
Would the PNF and Captain have had a better grasp of the situation had they SEEN a yoke held full 'nose up' ie with the PF holding the yoke right back, probably with both hands!?

I think...Yes.

Someone would have said 'push FFS!'
So why didn't the NWA 727 crew react that way back in the '60s? Why didn't the Birgenair 757 F/O do the same? They had yokes - I think the issue is more complex than that.

Automation makes you (and me) lazy.
So use your associations and unions to get the industry to accept more hand-flying, either on the line or off! If they argue that it's too expensive, just point out what this incident is likely to cost Air France in monetary terms, to say nothing of prestige and reputation.
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Old 17th Aug 2011, 00:41
  #2946 (permalink)  
 
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BBF is exactly correct, and his points suffer no loss of importance because other accidents turned out differently.

Trench warfare. Call a truce.

The commonality seen in recent accidents irrespective of type, Line, or Pilotage is how simple and horrible they appear in retrospect.

The part still that gets my goat is the apparent nonchalance of those doing the retrospecting. And the investigating, and the "improving".

None of these were "flukey". Bizarre confluence of highly improbable vectors? No, not at all. Straightforward lapses in Maintenance, engineering, training, rostering, and COMPLACENCY.

So one is left with hope alone. Not even Trust. Why Trust? Trust whom?

The tooth Fairy?
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Old 17th Aug 2011, 00:48
  #2947 (permalink)  
 
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Couldn't airbus come up with a design that lets you swing the sidestick either in front of you or keep it where you prefer on the side? Should be not too hard to do, after all I can adjust steering wheels in cars also (though up/down), and the concept that everything is electronic should make that implementation even easier...
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Old 17th Aug 2011, 00:52
  #2948 (permalink)  
 
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On sidesticks generally

HarryMann, back in the previous thread at 13th Aug 2011, 10:27, #1961, and later, again expressed his concerns about the AB side stick, and presumably side sticks in general. I agree with his other points, esp. the concern that the primary flight parameter, AoA, is very, very rarely instrumented. On sidesticks, no.

Harry, I graduated after other stuff to the Victa Airtourer, #2 pupil on #1 off the line, and later instructed on it. A side stick per se is *never a problem (& you do *not have to shove a aircraft physically 'round the sky if it’s controls are well designed.) In fact, given my druthers, I'd take a side stick any day, for precision.

IMHO the control problem, and IMexperience on AB, is the quite misguided removal of the tactile and physiological feedback that is so fundamental to the driver in the quite superb working environment of the Porsche designed AB cockpit.

The fundamental problem is that there is zero interconnectedness between the sidesticks, (even out of sight to the other pilot), and this borders on the criminal stupidity. There should at very least be a panic button on the stick which would put up the other’s stick position on the AH,PFI,ADI,PFD (choose one) like any computer game. When I was young and new to types I would ask the skipper if he minded my following through, and would place my little finger on the underside of the yoke. I then quickly knew *exactly what inputs were executed to achieve the required ‘product placement’ on that A/c.

That the throttle levers do not move to echo the fuel flow demand is (IMHO) another piece of almost criminal engineering ignorance and arrogance. So easy to incorporate that it implies a deliberate attempt to remove the pilot from the loop. The non-pilot’s dream of having control of an aircraft?

That the standby instruments are also computer driven is just the acid on the cake. And no, I’m not a recidivist, in fact a long time computer nerd. It freaked me when I first moved to the AB, the way various computers would crash and need repeated rebooting (‘resetting’) pre-departure in the *early 320. I trust they’ve got that right by now.

I've previously mentioned here about a total non-flags freeze-up of both non-steam-driven gauges early in my airline career, which needed a basic-instruments recovery at night while the skipper was stuffing fuses back in, after trying to fix the autopilot. Acutely aware all my years of what can happen, I made a point of flying limited panel for a while on a leg a couple of times a month to keep my hand in (all the obvious precautions, obviously) until the fast jet -- I doubt it can be done successfully -- but would then fly on the standby a.h. in lieu of limited panel.

I also hand-flew across continents at night three times when the A/P was U/S after departure, but when solid curfews meant that the complications would be horrendous -- because I maintained the touch. I hear the howl of horror now. Believe me, having the pilot *totally in the loop is the epitome of safety! I’ve had a check captain who didn’t comprehend a trimmed A/c, and demanded the yoke be grimly clutched at all times. (Incidentally, the phugoid oscillation frequency of a 727-200 is 20 seconds, and the divergence +/- 95’. Trim it, and it sits on height +/- 100’ with no intervention. (YMwillV on other type’s.)

None of this style of activity was ever suggested officially nor was there a sim exercise, but it instilled a huge sense of security, not just in me.

Early in one of these threads I stated that, in light of the above (too personal) ramble, & given my background (Gums’ ‘touch’), and my time on AB, that there was no way that I could have been able to fly AF447 in the situation they put themselves/found themselves in.

So forget sidestick fears, Harry. It’s the total lack of tactile controls feedback to the driver, and of awareness of what the other person is doing, which lays an unacceptable demand on the visual and computational ability of the brain. Thinking about it, has there been any research published on the maximum amount of data a person can process successfully process before the *brain stalls?

The situation that has so obsessed us here was IMHO the AB computer game crashing after a sensor failure, and was just as incomprehensible to the crew. It is why I was glad to retire from the beautifully built and so elegant AB, anticipating connector corrosion implications in 18-20 year-old aircraft, and now grieve for the innocents who have suffered.

(Retires to flame-proof bomb shelter for a week )
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Old 17th Aug 2011, 01:01
  #2949 (permalink)  
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Dozy.

Re your point 1. yep, having a yoke didn't save them. Perhaps these two F/Os might have been saved by the intervention of their Captain though, if he could have quickly grasped what was occurring?

He would have grasped it more clearly if he could have SEEN what inputs PF was making.

Agree?

Dozy.

Re my point about the autos making us lazy.

I guess you agree.

The less you fly, the less you CAN fly.

If you rarely fly, your skills diminish.

If you NEVER fly (and where I work the AP goes in at 1000 agl and stays in til final) you'll soon not be a pilot at all.

Surely 'piloting skills' ought to be valued in an aircraft pilot?

No.

Sometimes, as I'm driving to work, I think...'why am I flying this thing? what makes me the pilot instead of, say, an engineer- or that guy who taught me 'flat-panel'?


Or indeed, any guy who can wrestle the airacraft up to AP min engagement height!

What right do I have to call myself the 'grand fromage' pilot?

Last edited by BarbiesBoyfriend; 17th Aug 2011 at 01:38.
 
Old 17th Aug 2011, 02:39
  #2950 (permalink)  
 
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GY, great illustration.

Ladies and gents, if I may repost something CRITICAL to aviation safety ... from aquadalte ...

My dear Safety, I could not disagree more. The question is exactly the opposite. It is the technology that has to serve humans, therefore, it is the technology that has to be in tune with human factors. If you were a pilot, you would understand my point of view.
To serve man ... that is the purpose of the machine.

Period.
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Old 17th Aug 2011, 02:43
  #2951 (permalink)  
 
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Except that your analysis is not borne out in reality...

I have flown several aircraft with central control sticks from Cubs and similar light airplanes to fighter jets. I have also flown the AH-1W Cobra helicopter with a right-side control stick that moved (yes, actually MOVED) in the normal fore-aft and left-right axes. NONE of those were even remotely "painful." All of them fell naturally to hand.
No, a stick is pivoted at the floor - correct? And the hand grips the stick in the palm with your fingers wrapped around - right? This has a totally different movement and total throw, compared to a joystick type controller. The total throw is what... 3 inches max forward/back for the joystick. Very different and uses a completely different set of muscles.

I guess there are just folks that refuse to see to control for what it is - there is also a wrist rest - the arm doesn't move, only the wrist and fingers.
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Old 17th Aug 2011, 04:35
  #2952 (permalink)  
 
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Differing perceptions

GarageYears:

I guess all those joyful hours I spent flying Decathalons, Citabrias and Super Cubs gave me an entirely different perspective than yours. I find the "center stick" arrangement quite natural and easy to make precise control inputs with. It took me just a matter of minutes to adapt. It's not just me either.

Sidestick controllers came into vogue in the past couple of decades and I've yet to fly a plane so equipped. I'm sure they're fine too when properly designed with sensible force/motion/feedback (feel) built in. Long-EZ and Airbus pilots seem to like it. Pilots have adapted to a number of differing man/machine interface system designs over the course of aviation history. Some worked better and were more accepted than others. Some arrangements are better suited to certain missions. But you won't find many pilots with "stick" time who think it's a bad or even uncomfortable system to use. I'll agree that "center sticks" probably won't be anyone's first choice for installation on large transports!

The lack of motion interconnect on the Airbus sidesticks is something worthy of consideration though...
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Old 17th Aug 2011, 05:07
  #2953 (permalink)  
 
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JenCluse

Love your post and agree completely. Nice to see that more and more FBW experienced pilots (read this Safety?) admonish the absence of a vitally fundamental in Airbus cockpits.

As to the sidestick discussion:

There is no problem with a sidestick.
After 25 years of J3 stick, MD yokes, even the Bonanza Z-yoke, it took me 15 minutes to get used to the Airbus sidestick, be it with the left or with the right hand. It flies very well, is nicely precise, confirmed by all Airbus pilots.
I'd take a sidestick over a fossil yoke anytime, had it a tactile feedback though ....

What we focus on, is not what kind of a stick it is, or where it's located, but what it does.
Or what it does not and what the consequences are in terms of safety, stubborn denial from the lobby or not.
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Old 17th Aug 2011, 05:13
  #2954 (permalink)  
 
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No, a stick is pivoted at the floor - correct? And the hand grips the stick in the palm with your fingers wrapped around - right? This has a totally different movement and total throw, compared to a joystick type controller. The total throw is what... 3 inches max forward/back for the joystick. Very different and uses a completely different set of muscles.

I guess there are just folks that refuse to see to control for what it is - there is also a wrist rest - the arm doesn't move, only the wrist and fingers.
Not all sticks are pivoted at the floor. I've flown several (most) that had the pitch pivot at the floor, but the roll pivot higher on the stick. Also, floor height may be significantly different among types.

And, NO, I do not grip a stick in the palm! Depending on the airplane, different parts of the FINGERS are used to grip the stick (and occasionally braced with the edge of the palm), but SELDOM with the fingers wrapped around!

Regardless of the total throw, the grip on either a conventional center stick or a sidestick is VERY dependent on the individual installation. You apparently have little or no experience flying real airplanes with stick controls...

While there may be a wrist rest in SOME airplanes, and SOME sidesticks use no arm movement, that is definitely NOT a universal truth! A brace for the forearm or elbow may well replace a wrist rest. I doubt you could fly a Cobra without arm movement, though it may be possible in an F-16 or A3xx (I've flown neither of the last 2).
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Old 17th Aug 2011, 05:30
  #2955 (permalink)  
 
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It is the technology that has to serve humans, therefore, it is the technology that has to be in tune with human factors.
That the throttle levers do not move to echo the fuel flow demand is (IMHO) another piece of almost criminal engineering ignorance and arrogance. So easy to incorporate that it implies a deliberate attempt to remove the pilot from the loop. The non-pilot’s dream of having control of an aircraft?
Someone has finally grasped the direction design is moving in (bold text).
The technology is in tune with humans but the ultimate or primary goal may not be to serve pilots interests. We are in a transition phase to pilotless aircraft. The significant influence which will determine how quick or how slow this is implemented will be public perception

Many of you will remember the introduction of computers and hand held calculators. Apparently they were rubbish because they kept making mistakes in their calculations. The mistake however was more often than not the user. Rubbish in, rubbish out.

Early FBW pilots used to complain the aircraft did this or that without their input only to find out on examining the flight data that they did in fact move the stick and they did in fact cause the input.

In both the above cases very occasionally the system was at fault. Despite all the complaints at the time, I doubt there are many that support going back to human filing systems or the abacus.

I am sure many of you have used the driversless trains at some modern airports.

This harping on about the good ol days will not achieve much. There is no safety case. Even older generation aircraft had their own character including the spitfire which suffered from handling difficulties if the c of g was too far aft. Pilots however tuned in to the aircraft.

Number of aircraft in service, number of flights, number of fatalities all indicate proven technology. Humans remain the weakest link. Until the safety case is proven I still believe the argument should be about training and not technology.
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Old 17th Aug 2011, 07:08
  #2956 (permalink)  
 
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Safety

1. No one wants to go back to the good old days. Repeating that eternally doesn't make it true.

2. If you pretend that there is no safety case basically takes you out of the discussion equation.

3. Arguing that even on the other planes some guys crashed is only an infantile argument, not a valid one (look Mama, he did it too ...).
Look at the one in question, with its technology, try to fix that and then go on to the other.

You need to understand one thing:
To really and objectively judge if there is a safety issue, you need to have operated both systems (with and without feedback/driveback). Many pilots who actually have, joined us who ask to have all the new technology kept in the systems, but add tactile feedback to Airbusses. For the sake of enabling the pilot to better do what he is kept for in a modern airliner.
No engineer, no FS pilot, not even PPL pilots would have the real time experience of both designs.
This should not be taken as arrogance, but as sheer fact.

In science and technology there is no such thing as "that's the way it is, adapt or leave" (didn't I hear such [email protected] before? Right, it was something like "love it or leave it").
Science has to try different approaches, otherwise its results mean zilch.

I miss the differentiated approach to this particular issue. Instead of stubbornly denying anything could be missing, why not try and install such devices on a trial aircraft. Boeing had a sidestick with driveback developped, only to have the United pilots request back the yoke (now here is a classic case of what you described Safety, I admit and condemn).

Get it and install it.
This aircraft could then be evaluated by all sides in such replicated upsets.

I would certainly volunteer and go for such test for free.
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Old 17th Aug 2011, 07:40
  #2957 (permalink)  
 
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Been following the thread for a while and some good valid points are being put across from both sides but some folks are arguing for the sake of it, @Dozzy i think you are missing the point or deliberately trying to push peoples buttons, it had been earlier explained very clearly that the NWA 727 crew didnt push nose down though they had a yoke, simply because they both believed that their actions were correct trying to recover from a percieved overspeed as opposed to the AF PF who had no clue what he was doing and his PM had no way of seeing his control column inputs.

Now i crawl slowly back to my woodwork...
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Old 17th Aug 2011, 07:51
  #2958 (permalink)  
 
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"Pretending" there isn't a safety case.

In the 60's and 70's we had more accidents. We also had analogue aircraft with cable runs, AOA indicators and stick feedback crashing. We also had pilots who were human and unfortunately the biggest single cause of accidents.

In the 21st century we have removed the cable runs, removed the feedback (on some a/c), significantly increased automation but we still have pilots and we still have accidents.

Although the accidents have significantly reduced the number one cause is still pilot error yet the safety statistics and results of accident investigation show no significant difference between Boeing philosophy and Airbus philosophy.

Designers will be continuously monitoring operation and performance for improvements including of course accident causes. The aircraft are different, the way flying is conducted today is different yet there really is a valid argument about training and time "hands on". Is it sufficient?

There isn't however, yet at least, a valid argument about the technology. The industry remains driven by cost and safety. Until you can present a case that meets one of those criteria nothing will change.

On that basis it would appear that change isn't coming so industry has accepted that pilot error remains the issue and not technology. That is not meant to be derogatory just a statement of how it is today for those outside your bubble.
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Old 17th Aug 2011, 08:09
  #2959 (permalink)  
 
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talking about a bubble ....


so industry has accepted that pilot error remains the issue and not technology

Well, I think I have to rest my case, as the tecno bubble seems to have a greater surface tension, mainly financially driven, than the genuine safety concern bubble of pilots.

You know, the ones with their bums inside the thing.

Brave new world
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Old 17th Aug 2011, 08:10
  #2960 (permalink)  
 
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Originally Posted by RetiredF4 View Post
Would it get more unsafe in your opinion with feedback? Why not add feedback and an AOA gauge for aditional safety?
AOA gauge is there as an option already (I believe) - airlines just don't order it. An extra gauge will make no difference without training to use it - it might as well display phase of the moon. AF apparently couldn't be bothered to train pilots to manually fly in cruise at all (A/P goes off - learn to fly a new a/c, fast) - what makes you think they would have trained AOA ?

Feedback - well, it might improve things or it might not. Intuitively, yes - more feedback through more channels = better. In pratice, aviation history is littered with the smoking holes left by those who have ignored and overridden stick shakers and pushers, all the way to the ground.

The 'bus designers didn't just decide to do something different from shaker / pusher, they went for "better" with active protections ["limits" for Gums - but that's just semantics and audience because I sure wouldn't want to be the designer that tells a fighter pilot I'm going to "protect" him by limiting his control authority!].

Unfortunately, in this case (and perpignan) the protections were lost due to technical faults, leaving the warning system that is maybe less good than the old stick shaker. So question should be, is the overall system - active protections degrading to aural warning at 1 in 10k flight hours - better or worse than "stick shaker only" ?

I'd say they made it better. Could it be improved ? - certainly.
Should they go back ? - not IMO.

That is again a thinking in statistics and probabilities, i wont accept. Any near accident is too much, any accident is a waste. Why not improve things some more despite the relative high safety? Money? Pride? Neglecence?
By the way, its not A vs. B, its make things safer when you know how.
[...]
That is not a training issue alone, it is a problem to tune in the pilot into the system and to keep him in the loop from normal operation to the biggest f****up possible.
And this is also an engineering task, wether you like it or not.
That's agreed. The tricky bit is how to know what makes things safer. There are so many changing variables and so little accident signal buried in the statistical noise that you could find support for almost any change.

Human factors, and particularly human-machine interface is a complex area, and the little involvment I've had with it has given a clear impression of how counterintuitive it is.

Users of a system (pilots in this case) will happily tell you how they use it and how it needs to work - but record their usage with eye-trackers etc. and you'll get completely different answers. I would expect that to apply even to highly trained pilots and insturment scan - I bet that they weren't looking at what/where they thought they were when it all hit the fan in that cockpit.

The most interesting link posted on these threads (more than once)
was the Nasa study of A vs B control systems for CFIT escape. Covering sidestick, laws protections the lot. Result:
  • the pilots overwhelmingly thought B was the better system
  • the actual outcome was that the A system saved your ass more often
So which set of designers got it right ? Not easy.
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