Is the rudder pedal force sensitivity that much of an issue when a pilot pushes the pedal to the stop with a force of 140 lbs?

"BE GENTLE WITH ME, HENRY!!!!"
 

Have I missed something during the long transition from mil to civil aviation?

Or possibly neurons dissolved by too much sleeping lotion has erased the memory?

As far back as I can recall, rudder use in swept-wing aircraft was a delicate subject, as was the teaching of its use on the same 'frames.

On the Gnat Advanced training course in the RAF, we were given ONE demo of its use and effects at high altitude (to allow for the subsequent recovery if needed!) and that was it. Yes, squeeze it to remove drift before X-wind touchdown, but no more. The skin of the fin was cutaway on those 'frames with cracks in the attachment brackets, so we could compare them during walkaround, having "memorised" the crack shape and extent as we signed out the tech log in the line hut. Any noticeable discrepancy and it was back to the hut for another, please?!

This was as a result of fatalities due to fin separation in previous accidents as the phenominal rate of roll of that aircraft was the perceived cause of the early fatigueing.

Now it appears from the A300 accident that coarse and assertive rudder use was at one time being trained as an upset recovery technique. Where did the disconnect intrude into the mind of those who thought this was an acceptable and beneficial method of regaining control of a swept-wing public transport medium to heavy aircraft?

Forward the tape to the 90s and the recommendation from Mr Boeing that the full&free rudder check on the 747 should take 2 seconds from neutral to full deflection, both ways, and avoid crashing the rudders against the stops with coarse inputs.

This was apparently introduced as the routine inspections luckily discovered the PFCU attachment brackets were cracking as the barn doors on the 747 VS assembly were being crashed from side to side against the stops by the inadequately trained gorillas then operating them.

Fast forward the tape (yes I know, VHS-speak!) to today, and observe the massive rudder on the 73NG being slammed against the stops by the current crop of Captains, and if you don't see it from outside, then try sitting in the seats in the aft row and FEEL and HEAR the clunk as they hit the stops.

It gives me the chills when I feel it, and I am forced to ask what are the type-rating trainers and the line trainers up to by allowing this crass, clumsy and careless handling?

It all goes to show that there are some lessons in this game which we have forgotten, at our peril, when it comes to having respect for the flying controls and their effectiveness.

Are there any NG engineers out there who can reassure me the NG rudder assembly is NOT suffering from this abuse so that I'll sleep easier?

That "certification is "Europe" certification ! Terrifying !
Thank you misd-agin

Did the other aeronautical agencies try to copy ?

Have nice dreams BM !

there were a number of issues with this accident.

design. The -600 had different aileron control sensitivity to that of previous models. in turn, this led to the engineers tweaking the control loading required for max deflection, making the rudder more sensitive. this meant pio in yaw was increasingly likely.

this was a minor point; the big one was the negative training recieved in the simulator, in particular, the use of rudder to control roll during an upset. i believe, but am not certain, that the sim profile actually had the instructor turn down the control authority of aileron in the sim, and thus reinforcing the inappropriate use of rudder to control yaw.

a few on here need to do a bit of research. go off and read up on dynamic vs static loading requirements, then have a look at part 25 design requirements. understand the effects of moment of inertia, angular acceleration and aerodynamic damping and you will realise that no re-definition of Va has occurred.

do multiple, max amplitude in phase doublets on the rudder on any aircraft enough and you will snap the fin off.

I am going to have to get into an Airbus sim...

Slow flight, departure stalls, stall spin recoveries, wake turbulance, microbursts...

Probably all I will hear from the back of the sim...

'yeah, um, gee, try not to use the rudder to much...yeah I know the wings were 90 degrees and the plane was going to roll on it's back, but you know, um, well, gee, you see the tail hydros are really sensitive, and the tail, well, um, gosh, you see, well, the NTSB says the plane will right itself..oh, yeah, I know you were going to hit the ground, but you know, um, well, gosh, that's the recomendation, um, well, yeah, uh huh...'.

This probably has to be the most stupid conversaton on an aviation forum I have ever been part of.

Sorry to intrude lads, but back when this happened I was training in an MRO and our instructors ran the (approximate) maths to show the loading this fin was under. They came to the conclusion that any large jet transport aicraft would have lost the fin under that loading, composite or aluminium. The increase in load with each reversal was enormous. The fin on that A306 actually failed far above it's max load certification, our engineers were impressed at how long it held on for.

If you recreated the circumstances on a Boeing, Embraer or any medium or heavier aircraft, that many reversals at that speed that low will rip your tail off was their conclusion

UNA - There is no way your instructors were aeronautical engineers with the Airbus structural data, then punch in an accurate description of the wake turbulance event, then assuming they actually had the actual correct FDR inputs instead of some 'gamed' numbers, then of course found the only Arnold Swarzeneger pilot in the fleet that could bang 140 lb inputs back and forth in the sim to come up with 'sideloads' that imposed 'vertical loads' to take the tail off.

I mean I have been in the sim where I asked them to do a dual bucket deployment. ha. Trust me, these guys can't simulate the tail coming off. At best they can sit around a table with the numbers Airbus gave them, trying to convince the FAA that some perfect storm of rudder input and wake turbulance, conbined with a super special snowflake sensitive rudder system, that some how got through flight test cerfication, but you know, now needs to be recertified, because, you know..NOW they know it's quirky.

Come on.

I know that no one has asked, but … after reading the recent posts and looking again at the NTSB animation, I’d like to offer my thoughts … but before I do there are 2 things I need to explain:

1. Proprioception is awareness of the position of one’s body in time and a defined space; and the proprioceptors are located in subcutaneous tissues of muscles, tendons, joints that respond to stimuli applied to the body. There is conscious and subconscious proprioception – in a simplified description, one is recognized, processed by the brain, and recognizes a solution or response … and the other is not processed by the brain, the body simply responds … much like quickly jerking your hand away from a hot stove, or blinking your eye if it is threatened.
2. Anyone who flew the B727 very likely received a substantial amount of training on how to recover from a “dutch-roll.” And you probably recall that the primary control response was the aileron (control wheel) and the process was to recognize the direction of bank and apply a large amount of aileron opposite the roll, and immediately return the control to the neutral position. When the airplane began to roll in direction of your last aileron correction, and as soon as the airplane passed wings-level, again apply a large amount of aileron (control wheel) against the rising wing – or opposite the roll – and immediately return the controls to neutral. It’s the “return to neutral” part that is every bit as important as the control insertion to stop the “dutch-roll.” This is what all maximum control applications during certification require … return the control to the neutral position.

OK – now for my thoughts on the AA587 circumstance.

We know about the rudder sensitivity (if we call it that – but even then, the rudder shouldn’t have been all that much of an “unknown” to someone who’s flown the airplane as long as this crew had flown it) and we know that the F/O had quite successfully transitioned the first wingtip vortex (in fact, looking at the animation again – one could call it quite professionally – in that he allowed the inherent stability of the airplane to do it’s “thing”), but I think that encounter really heightened that F/O’s “fear factor” to the point that he was operating on “the panic bubble” – where he was not yet quite panicked, but he was right at the edge. Remember the F/O questioning the Captain about the ATC clearance, asking if the Captain was “comfortable” with the takeoff following distance? I believe the F/O was showing preliminary signs of nervousness, even before they pushed the throttles forward for takeoff. And I don’t think he had rid himself of that nervousness – I think it was peppering the back of his mind throughout the climb-out.

Pilots typically set up a mental regimen by which they fly (which might be described as …“scan – mentally process – feel – mentally process – scan – mentally choose a response – physically respond – scan – mentally process – feel the motion – visually confirm the motion cue – mentally process – etc.”). I think the F/O was riveted on flying the departure and controlling the airplane – and doing so more intently than he normally would. I think he was spending a lot of subconscious effort being concerned about where the JAL747 was ahead of them WHILE concentrating on his departure – still nervous but still performing. Then – bang, they encountered the 1st vortex. It jostled the airplane a bit – and I think the F/O did just what he was trained to do – keep the controls essentially neutral – correcting minor deviations as necessary – most notably, applying a very minor roll correction. And the vortex was successfully transitioned … but … and here’s the real BUT… I think that first event escalated the fear the F/O had been forcing down and brought it right up to scream in his face! I call it “the panic bubble.” He wasn’t panicked – yet. But he was nowhere near the calm F/O that questioned the Captain before the takeoff roll.

Had they not encountered that 2nd vortex, the F/O very likely would have taken a couple of deep breaths and, within the following 5 to 10 minutes, calmed down to the point that everything would have seemed to have been, and likely would have been, “back to normal.” I think he was beginning to mentally process what had just happened (what he saw, felt, heard … what controls he used, how much input, held for how long, any repetition required, etc.) as he began a turn to stay on the departure course … and he knew he had to continue the departure. I think the Captain noticed a change in his F/O – probably not overt … but a change nonetheless – and I think that was the reason he attempted to calm the F/O, and probably himself, by nonchalantly asking “a little turbulence there, eh?” just after the encounter subsided. But I believe that attempt at “down playing” what had just happened didn’t penetrate the F/O’s “panic bubble.”

He knew he had to maintain pitch, bank, heading, altitude, climb rate, airspeed, etc., follow the published departure AND follow ATC instructions – but I think he was more concerned about the JAL747 that he was following. I think those things grew and grew in significance and the panic bubble was growing, not reducing. Now he was trying to recall just how bad that turbulence had been and how bad it could have been. How close was that other airplane? In short, he was mentally pushed to the limits – but he was still trying to perform his duties of flying the airplane. However, before he could get things back into the regular process with which he was familiar … yep … BANG … 2nd vortex encounter. But here, the F/O was spooled up – quite a bit – and now, the panic bubble burst, and his response was one of panic – his proprioception receptors (recognition not requiring processing by the brain) fired, and knowing his airplane was being forced into more of a left bank – and having already established a 23° left bank – just like snapping your hand away from a hot stove, this F/O slammed a right control wheel and a corresponding right rudder control input – almost to the stops. Whether the following and all subsequent control applications (both wheel and rudder) were a result of his proprioception or his realization that what he just did was likely too much – I can’t say … but when you’re responding out of panic, there isn’t much room for recognizing magnitude and incorporating finesse.

Any pilot that takes 5 to 10 minutes to regain compsure isn't a safe pilot. By then it is all over. Maybe 5 seconds if he is slow. One second if he is normal. We don't have the luxury of time in the cockpit. Some things require immediate reflex actions, some don't.

Deciding to divert to an alternate, take your time. Wake turbulence or windshear a second is too long.

So, Teldorserious, how do you explain that in the aftermath of the crash, Boeing structural engineers did the same analysis and came up with the same answer - that the same rudder inputs would have failed the tail on a Boeing aircraft?

You never directly answered my earlier question - do you honestly believe the NTSB is corrupt and falsified the data?

And if you're willing to answer yes to that, I have another question: Why would they do that? Why would a US Government Agency falsify data to protect a foreign company - a company that competes directly with one of the USA's largest companies? And why would Boeing go along with it?

Oh, and while you're at it, why would American Airlines go along with it - exposing themselves to untold millions in lawsuits - when they could have piled all the blame on Airbus for a defective aircraft?

Or along the same lines, how do you explain that even before the AA crash, Boein issued an amendment to the Operating Manual of the KC-135 stating that reversals of rudder application can cause the vertical stabilizer to fail. (previously posted in this thread)

Interesting, isn't it, how Teldorserious just seems to ignore these things that don't fit her fantasy.

God, I hate having to repeat myself, but Teldorserious ain't an aviator in any form or fashion, so I fail to understand why any take his posts with any measure of credibility, or even engage him in conversation.

Brian;

It's interesting. Teldorserious started the thread and frankly, I like where the thread itself has gone; I have learned a great deal from others and am putting some of it to use in my flight data work.

But each poster sooner or later proves his or her capabilities as well as his or her disposition towards civility-above-all-else-including-ego, and serious discussion when engaging other like-minded serious professionals, many of whom come here for the joy at the level of such discussion as well as great information.

It's ironic that after beginning, his subsequent posts are puzzling, but there it is, not the first, nor the last occasion we'll see. He's been on my ignore list for some time.

As a freefaller we used unconscious proprioception and developed subcutaneous muscles and sensors like the dancers but we use too sight and other senses to control body attitude ref horizon or to join relative freefallers . During the freefall each time we leave the aircraft we fall first in low gravity and have to find the good dynamic balance with very little movements. As pilot, and specialy IFR pilot we do not trust proprioception. Itwould be a dangerous fault denying IFR flight possibility, but ONLY instrument informations -exception is position of the body in the armchair, neck position, and control of fingers, legs and fixing the inside of the body. As Bubbers44 says training overcomes vertigo created by contradictory proprioceptions. Performance in spinning armchair with blinded eyes used for astronauts training shows that difference : freefallers are much better than fighter pilots. Pilots trust instruments not body feelings.

Totally agree with the thrust of your post PJ2, only some have not learnt to ignore his exceedingly strange and ignorant posts. Renewing his instructors rating, give me a break.

Teldo... this comes to mind! :}

http://virtualmystic.files.wordpress...6/simcrash.jpg

SMOC, The statement "Personally, I would'nt let Buba pull my kids wagon" certainly applies to our friend.

OK465 - thanks for the correction/clarification.

I've seen a chart listing breakout forces, force needed for full travel, pedal travel, etc. I thought it was in the submission but apparently it isn't.

Brain are you still mad that I outted you as a fraud? Why the mods put up with your incessant trolling is beyond me. Maybe they don't care?

I’m not describing the necessity to compose one’s self … I’m describing the ability to not react out of panic, but rather function as you have been trained, choosing what your reaction will be – and I’ve described this in pilots as being somethink like …“scan – mentally process – feel – mentally process – scan – mentally choose a response – physically respond – scan – mentally process – feel the motion – visually confirm the motion cue – mentally process – etc.” this pilot was doing that up until the 2nd vortex … but I think he was on the verge of panic, keeping it under control, and likely, working his way out of it. Unfortunately, the 2nd vortex hit and burst that panic bubble – and from there everything he did (in my opinion) was the execution of what he knew but motivated out of panic. As I also said previously, most people think they know how to recognize someone who has panicked … perhaps some may … but I do know that when you’ve seen someone really panic, it’s something you won’t easily forget. And unless you know the person, or are really familiar with the circumstances, you might not recognize that the actions you see are very likely executed out of knowledge but that person is not calmly exercising that knowledge – he is being motivated out of panic – and that is something that is beyond the control of the person. In fact, the dictionary definition of panic is “… a sudden sensation of fear which is so strong as to dominate or prevent reason and logical thinking, replacing it with overwhelming feelings of anxiety and frantic agitation consistent with an animalistic fight-or-flight reaction.” To me, this is what I think that F/O was doing ... reacting with a skill set and doing so out of panic ... attempting to function without thinking logically or reasoning to any degree and was, instead, functioning out of an overwhelming feeling of anxiety and frantic agitation.