bearfoil

I am flattered you seem so intrigued by my possible bias. My bias is in opposition to:

Lack of complete disclosure, something I anticipate; for now, no harm no foul.

Cossetted product: "show your work"......

An anal retention of data, for as yet "historically ill-defined purpose"...

Secrecy, which implies a mistrust: of the Public, the industry, or themselves.

Evidently, an anti-mission "blunder", (the note) that was used by the public to assign blame, via urban myth, counter to BEA's charge not to assign it.

This "blame by public proxy" is despicable, not a mistake, and advantages a Party to lawsuit and potential criminal prosecution. As such, it is anti social, and anti democratic.

I am all too aware of the standard issue "support structure" in rapt attendance to an authority that has methods that are outdated, parochial, and serve not the best interest of the Public Safety.

Denial is not a river in Egypt.

what are your thoughts?


aside: As to: MLA. Airbus would not exempt the final protection (load) simply because of a faux CAS. Give credit where due.

JD-EE

henra, grity mentioned the aircraft's thrust. That's a stable system. So the real answer is probably between the two calculations you give. I'd suspect it is closer to the square of the delta velocity. (In fact I did a long ways back.)

JD-EE

Complete, 100%, disclosure is neither needed nor proper. Some things the public does not need to know and in the interest if the families involved should not be disclosed publicly. (Much of that data should be disclosed to the individual family if they wish.) This data is not needed to further the investigation to assign a cause not a blame.

It is neither BEA's job nor intent to assign blame. Therefore assigning blame with an incomplete data set and no serious knowledge of what caused the accident is certainly counter-productive and highly improper.

We have enough data to conjecture about cause. It's pretty obvious that the crash happened because (cause) the plane reached a full stall condition all the way to FL0. Then we ask, "what caused it to enter that stall condition?" We walk up the branching chain of possible events pruning out any potentially possible events that don't match the data on hand. This is what BEA is doing with a fuller deck of cards to play with. (I get giggles imagining one of the investigators reading this thread knowing things we don't and admiring the flights of fancy on all our parts.)

I see no legal definition conspiracy taking place. So far I see a remarkably open BEA providing enough data to the public for two serious purposes, to put down speculation and let the public know the level of data BEA is working with as reassurance they're on the job. We're taking this a whole lot further than BEA. And out of our discussions may come some valid criticisms of cockpit culture, training, system design, and hardware. (That's more or less my current sense of probability of serious criticisms. I'm biased, of course.)

Your postings seem to indicate you do see a conspiracy in the legal sense of the term. And you seem to presume things can fall off the plane in flight with no indications to the crew that get recorded in flight recorders or the ACARS message stream. This was amusing at first. It's gotten tedious.

I also see you being all over the map with an intent, conscious or subconscious, of someday being able to say, "See, I predicted the answer." I'm sorry I do not see the level of serious regard you may be giving the problem, if I am inaccurate here.

You asked. I answered as honestly as I can.

CONF iture

They wish.

bearfoil

And it is not forthcoming. fwiw.

JD-EE

Many folks here and elsewhere, know (approximately) what happened. Absent the exact details, an upset and LOC. Stall, leading to ocean impact. The precise daisy chain is and will be, fascinating. I am not trying to be facetious, the answer has been posted. Keep looking, it has everything to do with Physics, Electrons, and Mother Nature. A remotely possible confluence of poor fortune, poor performance (relative), and expectations. On the day 447 died, 1,000 people died in automobile accidents, and two thousand of smoking related illness, in America alone. It always produces snooty reactions when framed this way, for those who die in the air (or water), are somehow special.

Why? because for some reason how people die is seductive to humankind. I am full of grief for each soul who passes, every one. What galls me, is not the actual fact, but the residue of less than noble motives responsible for more than one would expect in the way of "death by airborn conveyance".

For each mechanic who wants to eat lunch and doesn't secure his forklift bearing a partially installed engine, there is a deliberate attempt in the boardroom to mitigate what are considered 'allowable' loss of life in the name of shareholder and pension, not to mention golden parachute.

For nuts, bolts, and sliderule types, you should make more money. Be more careful. See to it the line raises prices to reflect what an amazing and exciting endeavour is flight.

Success breeds competition. Grand success can breed ruinous competition, then the quality and safety of your travel starts to look like your meal, a hastily thrown together mystery meat casserole. We all deserve better.


TD: Do you expect an industry altering surprise? I don't. The Airbus has millions of hours, and was flown by highly qualified men.

Some hitherto unknown quirk of alchemy? Perhaps "Unknown aspects of fuel performance in Icing"? An unbelievably remote taptap freeze up?

I know that you are an engineer, and I value and admire your approach.
I hope to learn some of it here. Both of us are inquisitive, one of us perhaps a bit more suspicious of Humans than the other. I've been in marketing, Politics, Research, and many other pursuits. No one has ever gone broke underestimating the gullibility of the masses. Me included.

Trust is fickle, and once lost, a very arduous trek 'back'.

(modified my post, is it better?)

hetfield

BTW,

watch this, from another thread, starting 03:00

Turbine D

Read your last post, noticed one sentence:

Thought you left two words out: "Many folks think they know what happened."

In reality, few would bet their life, life savings, the ranch or their next paycheck on knowing for sure at the moment...

Poit

Hi PJ2,

Your reply to 3holelover was a very comprehensive and well written one. Both from a pilot-response point of view (which is common practice: power + pitch), and multiple systems and redundancies available for attitude indication in a large airliner (which was enlightening to me as well).

Your post very cleanly and succinctly draws the reader to the burning questions that are confusing most people with flying experience (myself included):

- Why the initial NU input; and
- Why the maintained NU input.

You were very diplomatic in not offering answers to those questions, and I don't think any of us can do until the final report is released.

Thank you sir!

jcjeant

Hi,

JD-EE
Only two causes are possible
1 The pilots made error
2 A defect of the plane
This is debated from ages on this forum
So far .. after reading the BEA preliminary reports and the note (and taken not in account all the speculations and technical stuff posted on this forum) .. the answer (until proved false) is item 1
All between 1 and 2 is armchair stuff
Like it or not ... but that's the life...

gums

This accident/crash will be one that lives in the books for a long time - many lessons-learned. And the "cause" will not be a simple pilot error or airplane problem.

Without posting 1,000 words, I can not believe that a modern FBW system does not employ a "standby gains" feature that uses air data from 2 seconds ago when the air data system becomes "suspect" by HAL or the humans in the cockpit. Hell, you could even provide a switch/button to revert to "standby gains" if you, the human, thought something was awry.

"HAL, I think we just froze up the pitot tubes, and remember that incident a few months ago?"

"Yeah, Gums, let's use some generic air data quantities while we figure this out"., and "don't worry about overspeed warnings and such while we work the problem, Gums, we ain't gonna die in ten seconds if you just hold current power and attitude"


That is not what happened, folks.

I am not convinced that a feature of one of the "laws" commanded an AoA or pitch that was not commanded by the pilot. After that, well, the pilot could have made things worse.

I am not convinced that aircrew training emphasizes the "don't just do something, just sit there", take a second or two and sort things out. In my little jet, we had less than a second to "do something", but it was the nature of the mission and what the jet was designed to do. The big heavies don't/can't move at 20 or 30 degrees per second in roll or pitch, but mine did. Those heavies have fairly benign aero characteristics, and with full control inputs you can't come close to the rates and such I dealt with.

IMHO, human factors will play a large role in the ultimate findings. Some will be training deficiencies, and some will be related to conflicting "warnings" and having a crew trying to figure out what "protections" they had versus simply flying a decently-designed jet with a basic control law to hang their hat on.

Poit

JD-EE

This is what BEA is doing with a fuller deck of cards to play with. (I get giggles imagining one of the investigators reading this thread knowing things we don't and admiring the flights of fancy on all our parts.)

I see no legal definition conspiracy taking place. So far I see a remarkably open BEA providing enough data to the public for two serious purposes, to put down speculation and let the public know the level of data BEA is working with as reassurance they're on the job. We're taking this a whole lot further than BEA. And out of our discussions may come some valid criticisms of cockpit culture, training, system design, and hardware. (That's more or less my current sense of probability of serious criticisms. I'm biased, of course.)

Hats off to you too mate. As with P2J, you're applying some much-needed logic and sense to what is (largely) for me a very interesting and informative discussion, marred by questionable contributions of a few.

I agree that the BEA have provided as much as they can at this point. Imagine the litigation(s) that would ensue if they published something that caused 'red herring' conclusions in the public domain. They have been as generous with information as they can afford to be at such an early stage, and I'm sure as much as is necessary will appear in the final report.

I'm also curious as to what a BEA investigator would think if he/she was reading this. For 'impartiality' reasons, I'm not sure they could, or would be allowed to. I think there are some valid theories here (with info available), but some of the more extreme makes me cringe...not giggle!

PJ2

Poit;
Thank you - I often wonder how such work is taken because there is so little response. I would not only never draw the conclusions regarding the crew, I can't because we don't have all the information.

Initially, I did posit the notion that the pitch up was a result of a response to the UAS memorized drill and checklist. Perhaps so, perhaps not, but that certainly wouldn't be "crew error" and could never be left to stand as such as a "single cause".

gums is right in stating "And the "cause" will not be a simple pilot error or airplane problem." There is no such thing as "pinpointing THE cause", and then being satisfied that one has "found out what happened". Such an outcome would be wholly incomplete and not true to the investigative process.

As I posted to Turbine D a few pages ago, there are indeed alternate plausible explanations to the pitch up, indeed I am aware of such explanations and cannot refute them. My post was more of an approach to the argument that a loss of attitude information "caused" the pitch-up which I doubt that very much for the reasons given. Each theory has to be explored, and whatever one can infer, logically, can be brought into the discussion with the understanding that it is merely a theory. Perhaps the data and cvr will resolve the matter, perhaps it won't. I think it will.

In any case, with comments done until then, I'm awaiting the next interim report.

Poit

No problem P2J, I too await the answer to the question. I recall you offering that theory (a 'pilot training/expectation' response), and as with other theories, it is quite plausible (if not concerning in the greater scheme of things).

As I said, the way you hypothetically approached the situation, (from the armchair, I acknowledge...I'm sitting in mine too),was methodical, logical, involved crew interaction about important initial actions, and crucial actions in the situation given.

As a frequent flyer (customer of airlines), I would expect a line-pilot, regardless of met conditions and given the situation, to apply the same. Wouldn't you?

I agree also that it can't be put purely down to either pilot, aircraft, or systemic failures. I was always taught that an accident was a serious in a chain, and as Air Force pilot trainees we were encouraged to break the chain created by other factors (ie be the human factor that didn't fail). Not always easy or possible.

Cheers

henra

In fact if you want to be exact, grity is right. The equilibrium of drag and thrust is only valid for one speed. So when the AC slows down in the climb, the 1g drag decreases. Therefore the thrust of the engines will add some energy to the equation.
However, this Delta of energy is negligable compared to the Deltas in energy state we are talking here. The effects of increased drag by maneuvering and changing bank angles will by far exceed the Excess thrust due to the speed decrease.

Between the two calculations I compared there is no doubt about which one is the physically correct one:
it is 1/2(m) v1^2 (Kinetic Energy before the climb) minus 1/2 (m) v2^2 (Kinetic Energy after the climb).

JD-EE

I think you guys might might not have seen this NASA toy before. The picture, A Flight of Helios, is rather nice and quite large. This propeller driven plane has made it to FL914, aka 30,000 meters on solar power only. Warning - it is a large picture.

(If it's too far off topic, John, please delete it.)

JD-EE

quoth bearfoil, "And it is not forthcoming. fwiw."

Rightly so.

The investigation is not over. Once it is over then there's time to prepare packets for the survivors with what is known about their particular victim or victims. I'm not sure I'd want to see pictures of a loved one after a couple years underneath the ocean and subsequent retrieval. There are levels of gruesome that bother me.

JD-EE

Turbine D said, "Thought you left two words out: "Many folks think they know what happened.""

In very broad terms I think we all know what happened. The plane took off from Brazil and the flight ended improperly slightly North of the Equator in the Atlantic Ocean.

Actually we know a good more detail than that. What we don't know for sure is what matters - what has to be done or what can be done to prevent this happening again?

JD-EE

jcjeant, I hope you know "the pilots made error" is not a good "cause".

Why did the pilot make the error? Can we determine this if that is the proximate cause. Is the real cause is faulty training and we stop at "the pilot make a booboo" the investigation served no purpose for the general public. And in that case I'd prefer the lower ticket prices had this investigation never taken place. If the data in BEA hands can lead to one or more aspects of training, manuals, instrument presentation, cockpit culture, or anything else that needs fixing, then fix 'em to the extent it's feasible.

Just don't stop at "the pilots made an error" or there was a "defect in the plane".

JD-EE

OK, I'll post a me2. PJ2, you have my complete respect here. You are one of the real adults in the room. (And I'm a Chatty Cathy....)

3holelover

PJ2,
Thanks for your well considered response... I agree with Poit.

I think there may be more than a few readers here who took me to be 'blaming' the crew for this.... Truth is that I've simply accepted the BEA's statement that there was not a problem with the aircraft (beyond the iced pitot probes), and I've started trying to imagine what causes may exist for the crew to misread their situation and provide incorrect responses. When I say the answer that best fits what we know so far is that the PF "screwed the pooch", I'm using an age old vernacular that I thought all who fly would understand... It doesn't necessarily imply that Ace McCool himself wouldn't have made the same incorrect assessment of the situation.

My original question was simply trying to find good reasons for the errors made. ...and I still think the answer may have had everything to do with what they saw and what they felt. ...and undoubtedly the sequence of same.

As an AME I'm well aware of the multiple contributing factors involved in any accident, and I know very well that blame can never be assigned to a single source. There are always other contributions along a chain of happenings. However, there is always the first line of an answer, such as: "Aircraft XXX fell out of the sky because the wing fell off." ...or, "The aircraft failed to stop on the runway because the wheels fell off." etc... Each and every case would have much more to the tale of course, with many important details, but the first line is not something that can be avoided.

In this case I've taken the BEA's releases at face value and have read the first line as saying, 'The pitot tubes iced, giving erroneous AS readings and the pilots failed to respond appropriately.' ....and now we need to find out why, yes?

In that, I can well imagine, given the situation they found themselves in, that many pilots might have made the same errors. I think in the seconds they had to deal with their multitude of puzzles and mixed messages, even Ace may have wound up in the drink.