I suppose another way to put it would be, that if THS remained +/- 3 degrees all the way up, would the a/c have started THS NU to counterract the -g the a/c "felt"(up to, through, and beyond the apogee?). Aren't the accels in charge of this protection? Would the PF know that the THS was trying to reweight the airframe, not retain the Stall? If this is what happened, the THS would articulate NU to the stop, since positive g at that point would be unrelated to THS position (all the way down), Yes? Is the 'g' protection active, then? Or just preventive?

Does this question have anything to do with Perpignan at all? Was Test pilot #1 trying to exceed 2.5 gees? To Pull up and away from the water?
Was the a/c actively prevented from more than +2.5 gee? Was 447 actively prevented from recovery from Stall because the PF did not know the THS had migrated all the way UP to regain +g? At 10,000 feet, was 1g regained, and the Tail became responsive again?

thanks, and much respect, Sir.

Hi Bear,
Without valid airspeed, yes.

It doesn't work like that: PF imputs, on flight control surfaces, are filtered by a function that would not allow excessives g-forces to be pulled out, even in direct law with an abrupt full deflection order.
http://takata1940.free.fr/Limits.jpg

@ Bear:
 

Note: (* added by me.

Flight Mode

http://i474.photobucket.com/albums/r...99/GeeA330.jpg

Load Factor Protection

On most commercial aircraft, the maximum load factor range is 2.5g/

-1g clean

and 2g/0g with slats and/or flaps extended. The load factor protection is

designed to maintain the aircraft within these limits while allowing the crew to

consistently achieve the best achievable aircraft performance, if required.

On commercial aircraft, high load factors are most likely to be encountered when
the pilot responds to a GPWS warning. Airline pilots are not accustomed to using
"g" as a flying parameter and experience has shown that, in emergency
situations, the application of "g" is initially hesitant and then aggressive. If a
GPWS alert is generated which requires an immediate pull-up, full back stick
should be applied and maintained. The load factor protection will allow maximum
"g" to be achieved in the shortest time while preventing the aircraft from being
overstressed.

http://i474.photobucket.com/albums/r...9/GeeA3302.jpg

Protected/Non-Protected Aircraft Climb Angle Comparison

If the pilot maintains full aft stick because the danger still exists, the high AOA

protection will eventually take over. This is one instance where load factor

protection is enhanced by the high angle of attack protection. (* Hi AOA Prot. NOT in ALT)

In "Flight Mode": "when no input is made on the sidestick, the computers maintain a 1g flight path."

In the zoom, we are in uncharted territory, so my questions may seem "thick". The Approach to STALL was through the back door of the Drag curve.

The Pilots and pax experienced a climb, one that when it came to an end, engendered up to or even more than -1g. As she decelerated, g was diminishing, the SS may have not been active, even if it was, it was likely ineffective, and at -g the computer will try to regain +g, Yes? Of course at this point they are aerodynamiclly STALLED, but the computers would still roll in THS (NU) to regain g? No other protection is available, and AoA would be an iffy way to regain aerodynamic flight.

From the dark side of the drag curve, STALL warn would not recognize the attitude re: STALL anyway, and the THS is the preferred method for reloading the airframe. The computers would have no interest in stopping the Stall, or recovering Flight, in AL2 they do not speak STALL RECOVERY.

When the PF made his ND inputs, the a/c reacquired sensible Warnings, but the a/c would sense ND as reacquiring -g, and keep rolling in more THS. So when the final STALL activated, the elevators may have signalled to PF a climb, rather than a ND, and he relaxed ND to think of something else.

I'll stipulate that the PF may have elevated the a/c into the climb, but once STALLED and even before, would not the computers be "protecting" "g"?

You know, after two years, I have to put on a serious thinking cap to prep for this thread, and PF PNF and Captain had seconds.

What was she doing? My understanding of the last seconds of Perpignan have the PF pulling everything to gain gee, and miss the sea. The computer would not allow >2.5. She kept her slippers on, right into the drink.

Bearfoil, you should stop dreaming that you will be able, any day soon, to rewrite the history of every "Airbus" already resolved crash without having a single idea of what you are talking about.

This is something I really don't understand about you... Those basic things are mandatory to understand how those aircraft are flying and most of this stuff, about Airbus FBW systems, is available nearly everywhere.

Why don't you take a little time to read it, all by yourself, instead of posting daily, from two years now on this thread, such a load of cr*ap about a subject you never bothered to study a minimum?

No problem. Adios.

C* (PITCH) Law, continued
 

Quote from DJ77:
"Please, what is this transition from g-control to pitch-control you are talking about and where is it described in the FCOM? Does it apply to A-330?"

Sorry for the sluggish response. If you thought you detected some hesitance or vagueness in my glossed-over references to C* (PITCH) law, you were right. The reason is quite simple: my only source of information is an extract from an A320 FCOM dated August 1987, six months before A320 type-certification, headed "British Caledonian" (joint launch-customer with Air France), which I obtained a few months later for my type conversion. That admitted, I doubt the fundamentals of C* law will have changed much in the meantime. But it amounts only to a brief introduction for us line pilots.

To answer the second part of your question first, Airbus have deliberately provided all their FBW aircraft with similar handling characteristics. A330 and A320 speeds are, I think, broadly similar. For example, on the A320, 210kt IAS is a typical "clean" holding speed below FL200, which has to be increased by 10kt or so at maximum landing weight. I doubt the A330 is greatly different. So the speed criteria used in C* are likely also to be similar.

My old FCOM says that C* law uses "normal acceleration as the basic parameter. At low speed, pitch rate is mixed with load factor [i.e., normal acceleration] 'G' such that at less than 150kt the effect of both G and pitch rate is [sic] equal. Above 210kt pitch-rate effect on the flight path is zero."

Later, it continues: "The overall effect of the law is that with the [sidestick] controller at neutral, the aircraft will maintain 1G and zero pitch-rate at low speed and 1G at high speed. As a result the aircraft is short-term attitude-stable."
[my hyphens, and my comments in square brackets]

In relation to AF447, I commented yesterday:
"The other unclear factor is how the C* pitch-function of the EFCS would treat the invalidation of CAS (IAS) data, when determining the crossover from g-control to pitch-control. As I understand it, that crossover is normally a gradual transition as the airspeed falls below a certain figure in routine flight. Understanding how the UAS affected this will be the other key step in solving the relationship between sidestick position, elevator/THS position, and the achieved trajectory."

Not big brother - no voting others off
 

Takata doesn't speak for me when he tells you to get lost.:{
This is not big brother so he doesn't get to vote you off.:=
JT has that right yet has chosen not to do so.:D
So, please, bear, keep probing, asking, seeking truth. I for one enjoy your contributions.:ok:
Sorry if I overdid the smileys.;)

Hi,

bearfoil
Unfortunately you can't refer to the Perpignan final report about gee
They released a bunch of graphics and tables but no one about the "gee" :*

http://www.bea.aero/docspa/2008/d-la...a081127.en.pdf

If anyone find one .. post here .......

Please "andianjul" don't encourage bear... see above. Yet MORE imaginary b/s from bear. There's a limit to what makes meaningful sense to extrapolate - but to simply make sh!t up seems shamefully self-fulfilling. We have facts, we have holes between those facts, but they mostly line-up to tell the story. There are those that want to believe that "the plane did it", but the facts (limited as they are) don't seem to tell that tale. That doesn't mean there can't be improvements related to the aircraft - every accident is an opportunity to learn and change things (if warranted) - but that also applies to pilot training, company procedures, etc.

:}

Hi Chris;

I'm not sure this helps but there are two documents, (rare) on C-star laws and fbw - they can be found at:

https://dspace.lib.cranfield.ac.uk/b...report9303.pdf
and,
http://www.raes.org.uk/pdfs/2989.pdf

They're really technical and I found them difficult but there were a few nuggets in there for a non-engineer retired Airbus pilot!

Bearfoil 13 july 00:09
Quote
The Pilots and pax experienced a climb, one that when it came to an end, engendered up to or even more than -1g. As she decelerated, g was diminishing, the SS may have not been active, even if it was, it was likely ineffective, and at -g the computer will try to regain +g, Yes? Of course at this point they are aerodynamiclly STALLED, but the computers would still roll in THS (NU) to regain g? No other protection is available, and AoA would be an iffy way to regain aerodynamic flight.
Unquote

Bearfoil, please get some education on flying before you spout more of this nonsense.
A zoom climb is not any uncharted territory.

In the most extreme case, when you decelerate to zero airspeed, you will have no more lift, so you will enter a free fall. How many G do you encounter in a free fall? Zero!

The minus 1 G that you conjure up could only be achieved by PUSHING FORWARD a large amount on the sidestick, yoke, steering wheel or whatever pitch control your aircraft has, while it still had enough airspeed to generate minus one G with a negative angle of attack.

I hope that this minus one G story of you, so that the computer would definitely roll in max THS up, yes? will make it clear to all how far off the mark you are. Please pay attention when people are politely trying to educate you.

As far as the lack of information from BEA is concerned - didn't they convey clearly that they have just put out a note:
"The BEA has decided to publish a note with information on the first facts established, based on analysis of the data from the flight recorders."

This note is not yet a final report, they need more time to analyse information.
Just imagine, they might first want to run a number of wind tunnel tests to check whether at 60 degrees of AOA there is enough nose down authority available to unstall the wing and recover the aircraft to normal flight. If they would not present proof about that in the final report, PPRUNErs would forever keep discussing about the point whether the a/c was recoverable or not.

airtren;
I think there are different meanings of the term "level" at work here - one for an engineer and one for a pilot, :) . Yes, the chances of it not "being on a "level" segment may be 4/5 or 80%, especially if nobody takes over the aircraft after the autopilot and autothrust has disconnected. But as you say, it is going to remain more or less level out of it's own inertia and the position of the control surfaces, etc. The pilot takes over and maintains cruise level and speed, (pitch and power), as I know you know.

By "stable, level flight" is meant maintaining an altitude while accepting small excursions above and below the exact altitude to maintain and not climbing or descending. It's never going to be "level" in the exact sense.

Is this what you meant? Tx...

Hi,

GarageYears
Maybe .. but why not encourage the BEA to release a graphic of the "gee" for the Perpignan case :ok:
Maybe it can be interesting.

Hi andianjul,
I'm speaking for nobody else than myself. I'm just feeling now like I'm feeding the troll for too long. If you are a member of the same fanclub, here is a good place to start reading about the aircraft: SmartCockpit - Airbus 330
and another good place to post and discuss whatever theory your imagination can elaborate without the need to read anything remotedly well documented on the subject: http://www.pprune.org/rumours-news/4...age-found.html
Now, my personal opinion is that a "technical" thread is not the best place for a conspiracy theorist (see above), but I may be wrong.

Have a look at HN39's post #70 where he explains the how the data was constructed.

With regard to the stall warning, it is designed to warn of an approaching stall and works on the basis that a stall is then avoided. When in ALT2 LAW the AoA value and the CAS must be within prescribed limits for the system to calculate, and when they fall outside, e.g. AoA > 30° and/or CAS < 60 KTS, the system determines there is No Calculated Data (NCD). No valid data has resulted in the SW turning off, and it appears that when the data became valid the SW resumed, but the application of NU commands to the SS has resulted in the SW stopping again. Result is an inappropriate action was rewarded.

Looking at the AoA curve in the graphic, it bounces along the SW line as the aircraft pitches up into the climb, briefly triggering the SW. The Stall Warning sounds at 2:10:51 and continues sounding until shortly after the Capt. enters the FD. Though not shown on the graphic, it later sounds when the aircraft is established in the stall and the data is once more valid following ND inputs to the sidestick. NU inputs stopped it!

A little in the way of personality clashes creeping in, folks.

If you or I, as in individual, disagree with what someone else is saying, then we should just ignore the detail or the post as you prefer. I will only censor if a post is blatantly outside our reasonable expectations.

Please don't get into the gutter and engage in tit for tat - not becoming for this forum and just moves the individual combatants down the respect ladder a rung or two.

C*
 

Thanks Chris Scott for your detailed answer about C*. I wil take some time trying to uderstand it better.

Thanks also PJ2 for the references to C* docs.

The curve shows the stall warning threshold. It varies with Mach number according to a schedule that has been posted by A33Zab a few weeks ago. Except for the NCD condition explained by mm43, stall warning begins when AoA exceeds the stall warning threshold, and continues until the AoA has decreased below that threshold.

Hi Takata,

I think Bear was asking something like:
During the apogee when sensed g is less than 1, and stick free, will the FBW logic increase pitch in an attempt to hold 1 g?

Some of my students use the term "g" when they meant to say "delta g".

I'll chuck this (2000) paper in too if it helps.

Fly-By-Wire A Primer for Aviation Accident Investigators

Hi BOAC,

Your paper sums up in one sentence, what I've tried to say.
Once stall "protection", "limit" in Normal Law is lost - PLEASE return my "elevator feel" with Direct Law.

It might be a good idea to return this thread 'to earth' with a brief summary of what we know.

Leaving aside what happened after the climb, what about the climb?

1) There is nothing in the BEA report to suggest that the aircraft caused it itself. The only 'query' here is the track record of system reaction to 'events', like the QF pitch anomaly and the 2001 North Atlantic altitude excursion with TC-JDN. It is worth noting that in this the crew did not trigger a climb. (There is some confusion (for me) in the AAIB report where the FDR traces suggest the TCAS RA occurred BEFORE the a/c left its cruise level). Had this crew been in the ITCZ at night and not in clear air in daylight it is worth contemplating what might have occurred.

2) There is nothing in the BEA report to suggest that the pilots caused the climb either.

Until the BEA provide the full CVR transcript AND RHSS trace from the FDR for the period 2:10:05 to 2:10:51 we are all guessing. Why they have not is a mystery to me.

If you ignore the slight complication of no-lift angles and wing body settings (which change the zero body angle downwash), then lift coefficient is just AoA times lift curve slope, so they move together. Almost all textbooks and reports use the AoA format as this makes the equations a bit easier to handle. I guess I just stuck with it from force of habithttp://images.ibsrv.net/ibsrv/res/sr...lies/smile.gif

The numbers I quoted are pretty good for an aircraft like the A330, at least up to stalling AoA. When lift curves go nonlinear then I would agree with you that lift coefficient would be a better handle. I don't think anyone knows exactly what the downwash would be at 60 deg AoA, but I was using it in an argument about THS stall and as the later bit of my argument took the THS away from stall I didn't worry too much about ithttp://images.ibsrv.net/ibsrv/res/sr...lies/smile.gif

Thanks for the welcome!

Takata, #204

I'm afraid not. The voluminous fcom looks to me like a user guide,
rather than a serious technical manual and the logic that drives the
transitions between the various laws is not available anywhere, afaics.
Perhaps you could provide pointers ?. Sure, the fcom has bits and pieces
dotted around all over the place, but nowhere can I find a flowchart or
logic diagram that describes the whole process. The fact that, ergo, ab
seem to think that this is not important to crew is one of the most
worrying things about the whole episode. Fly the computers, not the a/c,
seem to be the modern mantra and you don't need to know about the
detail :eek:.

Are the personal, ad hominem attacks really necessary ?. If you don't
like a post, then don't read it. It's not as though you had anything
constructive to say in rebuttal anyway. It's not the way that it's done
here, so please, let's keep it civil...

takata
 

Sorry,but I find that takata`s outbursts are unpleasant and confrontational and not really required.Everyone is doing a fantastic job here with lots of team effort to try to discover what caused the death of so many innocent people,and that includes bearfoil.Some are more qualified than others and some have other agenda`s that are not easy to see.Sometimes those from without Looking In have better vision that those inside who may not see the Wood for the Trees......pull together guys and girls.Works much better.

BOAC, #222

Other than the sidestick input, yes ?.

Something that occurred to me is the fact that the sidestick transducer,
which translates physical input to electrical signal, could have failed
in such a way as to provide a bias in it's output. Don't have enough
info to know if it uses a synchro, resolver, potentiometer or optical
encoder, but any but the last of those could in theory degrade to
provide a bias away from zero, (ie: nose up) depending on failure mode.

Probably a long shot, but it is a possibility...

It is completely understandable that frustration surfaces when repeatedly confronted with fantasies, ignorance of facts, invention of facts, rewriting of facts and then attempting to mask it by consistent use of gobbledygook.

Loerie,

What you have here is a bunch of people running in circles and they have done so for quite a while. Some have even resorted to just spin around them selves.

Try this little experiment; Select at random five people who regularly posts on AF447 threads 1-5, select at random five posts from each, compare the five posts. If you can spot any difference let me know.

Maybe, but I'd say that they were fairly understandable.

Actually, I'd say that Bear has been deliberately trying to obfuscate and make things unclear in order to push his own agenda - the fact that he elected to do it so prolifically in the last few days does not help his case.

One of whom is Bear. I'm all for getting as many heads around the table as possible, but what he was doing was tantamount to spamming the thread - not just with questions, but with statements that were (based on the information given) demonstrably untrue.

(I hope this won't be construed as being "personal", this is just my observations from the last day or so)

@rudderrudderrat : There has been no such thing as real "elevator feel" since the '60s, and Direct Law does not provide it. The only difference between Normal/Alternate and Direct Law when it comes to tail surfaces is that the trim movement becomes manual-only in the latter, and the elevator command directly affects deflection rather than commanding a rate.

@KBPsen - some of us have been effectively forced to repeat ourselves because of the drip-feeding of misinformation that you are describing - in fact quite a few genuinely knowledgeable people have got fed up and only pop in occasionally, if at all. That's probably a major source of the frustration right there, because if some of us don't fight to keep the discussion to the facts then we could end up with some of the misinformation quoted in a newspaper somewhere, and that's how fallacies like "The plane thought it was trying to land and overrode the pilot" get spread around.

FBW Investigation Primer
 

BOAC posted an intressant link; Fly-By-Wire A Primer for Aviation Accident Investigators
I have enjoyed reading the short description of how FBW systems operate and about C, C*, and G*U. In principle it looks almost like normal PI controllers and not PID ones. What strikes me is that all is written with the assumption that the controllers are analog and not digital. From my own experience - writing well performing digital controllers and their real-time performance is a very different story.

Regards

@ syseng68k:
 

2 Xdcrs(contains 4x triple potentiometers per axis).

FCPC1 & FCSC1 driven by separate linkage. (Dual Channel output 4 potentiometers, 2 unused) per axis.
FCPC2 & 3; FCSC2 driven by the other linkage (Dual Channel output 6 potentiometers) per axis.

The sidestick is placed in a polycarbonate container to prevent entrance of foreign matter.
The sidestick design is such that rupture, disconnection or jamming of any of the parts can't cause the loss of total A/F loads on one axis or block free movement of a set of a potentiometer group related to one axis.
Transducer output is monitored and compared, if any difference F/CTL L(R) SIDESTICK FAULT ECAM message is triggered.

Schematic:

http://i474.photobucket.com/albums/r.../SideStick.jpg

Stall Warning Threshold curve
 

Thanks for your clarifications

Then it would seem that naming of that curve "SW threshold" would make the graph clearer/self explanatory. A "SW" curve (could be non-contiguous) could be the curve representing on the time scale the intervals when the Stall Warning was (should have been) active.

As I looked again at the graph, I thought it would be helpful to see the corresponding curves/data that were available to the "a/c systems" and "a/c pilots" in the context of "loss of data", and showing the discontinuity in the SWT (stall warning threshold) curve, due to NCD - was there such a graph already made available?

The Stall Warning ON->OFF->ON->OFF transitioning during the Stall is one of the several elements that seem to be in the most troubling category. Would this qualify the SW during the event in a different type than "lack of info"? Would it be, the "FALSE info" type?

Is the calculation/equation used for determining the providing of the Stall Warning relying on too few parameters?

"Vertical acceleration", or "vertical speed", perhaps "no lift"? Is any of the existing sensors, and parameters available on the "a/c" able to provide info, so that a Stall Warning could have been clearly brought to the knowledge of the pilots for the entire duration of the Stall?

syseng68k;

Re your post #224, good observation. The FCOM is a need-to-know user's manual and indeed does not explain the aircraft. I think this is one of the underlying issues. FBW and C-star law are not in and of themselves problematic but unlike complex hydraulic or electrical systems, the differences in "the how" of control are materially different and require understanding, as do the more bread-and-butter areas of high altitude, high Mach number flight and even some jet transport aerodynamics. I did not know and did not understand until a lengthy and patient exchange with HN39 that the stall AoA for my aircraft was much lower at high Mach numbers in cruise flight than what Davies had expressed in his wonderful book, which was the approach and landing case with high-lift devices extended. Big, big difference and, even in retirement, I learned some fundamentals.

These are not taught very thoroughly in initial ground schools at least in my experience, and if one wasn't in the air force one's knowledge was increased largely through one's own efforts.

The frustrations of not knowing and not being able to find things out easily have been endemic - while easy to fly and a joy to hand-fly, "automation" has become as much a marketing tool as it has a way of solving the problems of flight. The resistance to knowing more than the "NTK". need-to-know, ground-school curriculum requires, comes first from how expensive it is to train well, and next from a lack of knowledge in those who must do the teaching, always of course, with wonderful exceptions from those memorable instructors who's passion takes them, and their students beyond NTK.

Learning is expensive and NTK and automation are assumed to "solve" that "problem" for a cash-strapped, (de-regulated) industry.

This isn't "THE" problem, because clearly the aircraft and the design's record is no worse in terms of fatal accident rates than conventional types - in short, the airplane and the design work extremely well but one should never be in a position to not understand and not anticipate what his airplane is doing.

Below is a nuts-and-bolts schematic of the pitch-basic loop. I hope it is of some service in understanding the pitch control of the A330.


http://www.smugmug.com/photos/i-RvKW...RvKWdbv-XL.jpg

Takata: When the g load is less than 0.5g then the THS is frozen. Perhaps this is not known to Bearfoil?

Meikleour

It was not known to me, and I appreciate rudderrat's rephrase. I'll be brief with my next question. Of course it may (is) in the FCOM, but may I see any answer in the thread?

If frozen, the THS would be unavailable for Trimming, (or Pitch changes), until what point? When does it become available again?

So the original question remains: If less than one g, does the THS move independently of Pilot's inputs? Does it try to regain 1g or satisfy itself that anything greater than -1g is acceptable?

Does it "Unfreeze" if the g becomes <-1g? And then input NU?

The limits are intriguing to me, until I have a better picture of what the THS may have been doing in <1g, who can say what the a/c's behaviour was?

To expand on BOAC's #2, BEA have not assigned the climb to the pilots, that is true, and they affirm that by specifically stating, "ONE" (a) Noseup, left roll input. That apparently happened prior to the "climb", as I read it.

Hi BOAC,
There is another way to change pitch attitude than pulling up on the sidestick as simply applying thrust could do the job if the ammount is large enough.
While I agree that QF event remains a mystery, TC-JDN case is showing that, right after autothrust disconnection, manual thrust was applied and increased from N1 below 70% to 100%. Sidestick (ND?!) imputs were not applied until the top of the climb 30 seconds later, hence nothing contraried TC-JDN to change its level flight. Someone also posted a revised chart of DFDR control imputs but, as far as I remember, it did not include any thrust track.

There is some more confusion (for me) in the AAIB report and in the cockpit. Had this crew been in the ITCZ (or anywhere else at night) it would be certainly dangerous, but they still were in NORMAL LAW and the flight envelope, contrary to AF447, was still fully protected as airspeed was valid all the time.

Well, I should have read another "report" as in mine, a nose up order was (almost immdediately) given by the pilot... the later nose down orders that were applied only reduced the climb rate from 7,000 ft to 700 ft/mn (which is not enough to start a descent). So here, we effectively need to see the tracks in order to understand what the PF really wanted to do. It is not like this initial climb looked like uncommanded, but the report doesn't tell much about how it was controled and what could have prevented this high climb rate control by the PF.

To start with just a reminder of BOAC's justified concern that these curves should not be mistaken for real DFDR data. What you are asking is problematic because the curves assume still air, and one should be aware that turbulence would superimpose "grass"-like fluctuations on most parameters. IMO that is the reason that the two brief activations of S/W after 2:10:05 are not shown as threshold exceedances on mm43's graph. May I suggest that you just make a note that the AoA was 'invalid' between 2:11:40 plus 'a few seconds' and 2:12:17?

The systems consider the signals coming from the AoA vanes invalid, there is no discontinuity in the SWT.

You pose more valid questions, but I regret not being in a position to answer them.

HeavyMetallist, "Why some people persist in believing that stalled == totally ineffective is a mystery."

gums has posted some graphs that show an actual inversion of control for a totally different kind of aircraft when in a bad enough AoA configuration. Somebody else posted a graph I believed was for the A330 produced by calculations that indicated an AoA of 61 was sufficient to put the A330 into a realm where the tail was not particularly effective.

That said, it appears from the release, in a part I'd forgotten (take your own advice, Joanne), that there still was some authority from the tail surface. Unless the PF pulled up again after the stall warning the tail surface did not have enough authority to pull them out in the remaining 2 minutes. So it was basically ineffective or marginally effective.

Stick mechanism
 

A33Zab
Thanks for a nice and illustrative picture of the stick mechanism.
I wonder if a very strong force on the stick to the left could force some undesired nose-up if the enclosing structure is not sturdy enough.
I am also a little surprised that potentiometers are used - even with two (or more) in parallell for each axis.

Regards

bearfoil, you'd best concentrate on something you know somewhat better than law. I can think of several instances off the top of my head wherein people who are not parties to a contract or any other record do not have access to the data.

One is when a settlement is reached and both parties insist it be kept secret as a part of the settlement.