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Old 24th Jun 2009, 20:26
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DJ77 AMG65 and AMF

But AMF's description should be supported by references to theoretical or experimental studies or even personal experience (if any). Otherwise, it looks like fiction.

See, for example, Tim Vasquez's analysis: no updraft higher than 40kt (about 4000 ft/mn), not "18000 ft/min, even higher" as mentioned, and no heat sink signature observed.

Of course, I don't intend to suggest that the pilots were not faced with a very severe situation flying in (or close to) bad weather without reliable airspeed indication.
I've already posted on this and the previous thread the basics of high altitude aerodynamics, and given the approximated weight of that aircraft at 35,000' others have referenced the buffet margins and turb air penetration speed they'd be dealing with. My question to you would be have you ever actually hand-flown a jet aircraft near the upper limit of it's performance envolope in smooth, still air, let alone with moderate or higher turbulence? Your answer makes me doubt that very much.

And if you're downplaying an aircraft traveling transitioning laterally through even 4,000 fpm gust cores while near it's maximum altitude then it only confirms my previous suspision as to your experience.

Personal experiences? Sure. I learned to fly and spent the first almost 20 years of my career operatiing near and through what's considered the worst severe weather area on the planet, the mid-continental U.S. That experience includes 2 spring/summer season of Weather Modification, primarily hail supression where we didn't even take off to play chicken with them unless the CBs were at least Level 5s.

Experimental studies? As an offshoot of this program, we also (in the early/mid 80s, contracted by the governement) also had the displeasure of doing some of the early airborne-gathered data flights in the infancy of microburst reasearch by flying specially sensor-equipped aircraft for the explicit purpose of finding out what was going on inside a convective storm in order to correlate it with what ground and airborne-based radar sees. Microburst hunting, if you will. I will tell you this; for that program we did NOT enter those Level 5 or higher cells, nor did we enter ANY cells (or transition directly above developing cells) while at high altitude near the upper edge of our envelope. There's a world of difference encountering such forces at mid and lower altitudes (at the least extremely uncomfortable to quite possibly perilous) compared to high altitude (always an extremely perilous seat-pincher).

There's also a reason the CB penetration flights used to gather data on the probablilities of encountering differing degrees of light-to-extreme turbulence and hail diameters within CBs when they were working to devise the descriptive sytem of Levels based on reflectivity we still use today were accomplished in aircraft like F-106s.

Nothing has changed in that regard over the last 40 years in civil aviation no matter how efficient aircraft have become. They aren't designed for it. I've certainly flown with some nowadays, however, that don't know how the contours they see on their airborne wx radar correlate to CB levels, or worse, what the dbz levels of reflectivity are actually describing as it concerns the pilot; the varying degrees of probability of encountering low/light upwards to high/extreme turbulence, and low/small diameter to high/large diameter hail. BUT, as any pilot who's operated x-band radar knows, there are some prounounced limitations to getting the full picture.

Back then in the 80's maybe the accident lessons they had learned when transitioning to jets in the 60's and the unforgiving nature of high-altitude flying were still recent enough to drum into us and people took heed. Everything in my flying experience after that confirmed what I'd been taught, and my experience isn't limited to simply tooling along in level flight, on A/P, twisting a heading bug now and then to half-bank around the occasional cell. It's no "Hollywood" fantasy to know that convective weather and high altitude flying don't mix. From what I'm reading here though, I'm beginning to believe that a lot of those lessons have been forgotten, or downplayed over time.

Tim Vasquez has done an exceedingly great bit of research, but no matter how great your pictures or theories are, they are too macro and dependent on reflectivity levels and satellite imaging to truly see the full picture of the micro-level (meaning laterally small), severe dynamics contained in CB cells that can wreak havoc on an aircraft. When I was younger and braver, I helped collect data on just that in search of microbursts and their nature and as an offshoot CBs in gereral, directly experiencing how CBs can affect an aircraft in flight (with various air data recorders running for delivery to the much smarter folks than we)..not simply postulated what might happen based on sattelite imagery.

Last edited by AMF; 24th Jun 2009 at 20:42.
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Old 24th Jun 2009, 20:41
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Captain Kirk are you really Ernest Gann?

Its very possible that the scenario encountered in this case could well have been outside of the ability of any pilot - however experienced. Therefore contributions highlighting the inexperience of fellow officers, while fascinating, are perhaps not relevent to this thread at this point in time.
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Old 24th Jun 2009, 20:50
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DJ77 quote..


Nice scenario ... for Hollywood.

AMF quote . . .

If you think that's a "Hollywood" scenario, then it tells me you're seriously lacking in knowledge when it comes to high altitude aerodynamics and experience with regards to hand-flying jet aircraft near the upper edge of it's envelope and the danger that lies just outside it, as well as obviously not very familiar with operating in close proximity powerful CBs on a routine basis.
To quote D.P. Davies' book "Handling The Big Jets" Third Edition:

The caption on plate 12, Flight at high altitude, opposite to page 109 describes it very well in a few words . . .

"It is difficult to express in a photograph the almost etheral quality of flight at very high altitudes-( . . . . .). In this picture, however, the photographer has managed to capture something of the atmosphere found at 35,000 feet. On a more practical level one should bear in mind the effect of this rarified atmosphere, which is to reduce aerodynamic damping. Because of this the pilot must be gentle with the aeroplane when manoeuvring."

The image on plate 12 illustrates relatively normal, daytime weather conditions at 35,000 feet, serene circumstances compared to what the AF447 crew may have encountered that night, possibly hand-flying a crippled airplane in rough air at high altitude.

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Old 24th Jun 2009, 20:56
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Declining pilot skills is an issue but by discussing it here we infer it was applicable to 447.We cant know that.
Lemurian made an assertion that the pilot can override the Flight Control Computer commands if the pilot feels that those commands are based on corrupted sensory data.How is this achieved?Can he break the chain only at the source(de-select ADR/IR) or can he intervene at the control level(de-select PRIM #)?Is there a recognized procedure or is it astronauts-only?How much lateral-thinking and system knowledge would be required in the diagnosis and corrective action?
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Old 24th Jun 2009, 22:13
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Vertical Stabilizer - Recovery Location?

Does anyone know the debris recovery number for the v/s per the data released by BEA on June 17?

Or, does anyone know the actual lat/long the v/s was recovered in?

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Old 24th Jun 2009, 22:28
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So, you are the preiminitent expert on pilot training, pilot evaluation in checking events and you wonder where the industry is going? I have been an evaluator in US 14 CFR 121 operations since 1992, including examiner for ATP/ATPL and instrument ratings in heavy jet airplanes.

In my humble opinion AF would never crew the flight deck with other than fully qualifed pilots for the position they served in. This is in accordance with required training. At least two, if not all were fully type rated and current on the airplane. The differention between Captain and First Officer is blured in the general public. A Captain is nothing more or less than a highly qualifed and experienced pilot designated as Pilot in Command in US FAA language. He is in absolute control, but he can designate. Very similar to when I go take a piss inflight and announce "Captain is off the bridge, FO has the Con" This is just for fun

FOs upgrade to Captain hourly on a world clock. Does this make them less competant as a PIC? I highly doubt this. I truly understand the search for knowledge on this forum, but some of the participants on this forum require me to just ignore, stand back and hope the true aviators set up a restricted message string.

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Old 24th Jun 2009, 22:29
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There are three main reasons for a/c accidents:

(1) The pilot: Prime suspect, if only for the reason that he/she was the last to touch the a/c.

(2) Mechanical failure: Increasingly rare these days thanks to better design and testing of materials.

(3) Systems failures: Unfortunately creeping up the league table.

I admit I am not a jet jockey, but I have found myself in turbulent air in IMC. Before the a/p tripped I would take control (it was a crude a/p system), the reason; not many recover from unusual attitudes in actual turbulence, much better to take control of a stable aircraft and fly attitude/power.

With advanced systems, the a/p can probably fly the aircraft better than the crew, certainly more economically. When things start to go south, however, the system compensates with its built in redundancy (therein lies the danger). When it finally gives up, it hands over a, probably, uncontrollable aircraft to an inexperienced crew. I do not mean to be derogatory with the term inexperienced, my good buddy is a TC on 777s and I have nothing but admiration for his skills; but I would not class myself an experienced aviator if I switched in the a/p 12 secs after take off and off after landing.

Remember that when you do your sim/flight training you're geared up ready for what is about to come your way; much different to being in the cruise at FL350 on a dark night in the middle of nowhere.

Training has got to start including, recovery after major systems failure or better still recognizing the onset of a systems failure and stopping it becoming another AF.

I'm not optimistic that that can be achieved, humans are not good at monitoring computers; much better the other way around.
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Old 24th Jun 2009, 22:47
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tquehl: thanks

if you check the flightexperience of the FO its unlikely he was a relief pilot, so all 3 were qualified..

good night and good luck
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Old 25th Jun 2009, 00:57
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Captain Kirk;

Your post shows both wisdom and experience - there are a number of us here who could have, and who indeed have, posted the same commentary on the industry.

Captain Sullenberger's presentation before Congress in February of this year was an excellent summary of these current, and disturbing, factors in our profession and a good summary of a number of posts here in the last few pages. Well done, sir.

(Retired A330/340 captain)

Last edited by PJ2; 25th Jun 2009 at 04:08. Reason: Typo in Captain Sullenberger's name - thank you.
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Old 25th Jun 2009, 02:19
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'Out of the FOG' Capt Robert Scott

Try searching RAES - Home and email the contact address and ask them to send it to you...

if no luck I will scan and reproduce it.

He is a FRAes and member of the Society's Flight Operations group ( hence the section is titled out of the F... O.. G.

That should help a bit.

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Old 25th Jun 2009, 03:52
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Criticism about young pilots

Some of the postings here suggest that todays pilots are less proficient than they used to be. I would belive you should avoid generalizations like this. Looking at some accident reports of 1970 till 1990 you would find a lot of fuel to sustain your fire.

You might very well find that pilots training needs to be revised. I remember the quotation "...everybody can fly it, even the woman cleaning my office". He was talking of A330 and everybody in aviation should know to whom I am referring.

Somehow, talking of my oppinion, this philosophy made its way into the Cies in the quest to reducing costs wherever possible. I have no idea, if handflying the a/c at optimum FL under "Alternate Law" is part of Sim-training at AF, much less so with partial panel.

Consequently I would presume, even IF the pilots would be found 'responsible' for the loss of control, they would not have had a real chance without the proper training.

Remember, You do the drill in the Sim, so that you already have the proper answer ready for most of the abnormals that could happen inflight. If it was this what happened. Some interresting documents seemingly by AB/AF dealing with Unreliable IAS as of last year, at this site:

If true, why didn't they change the pitots earlier, we are talking now of two years of related problems and more than 30 cases.......

For the Top Guns here I have about 7k Landings, about 14 Autolandings (some Trng, some CAT3), the rest by hand, of course.

Awaiting the heat........
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Old 25th Jun 2009, 03:57
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PIC found

According Crash-Aerien, French pilot's Forum, the body of the Captain has been among those already retrieved. No further details given.......
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Old 25th Jun 2009, 04:05
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Awaiting the heat........
No heat from me or many here - I agree with you. - it's training, training, training, all the way down and robust check rides that go back to high standards and being brought along by instructors who know the airplane inside and out.

When introduced, the 320 then 330/340 series required a new understanding of how flight controls and automation worked - the airplane is obscure and confusing only if a student was offered barebones groundschool and eight simulator sessions before flying the airplane under supervision.

For the vast majority of new candidates being hired, there is nothing "wrong" with today's young pilots that an appropriate level of training and experience gained under supervision can't address. "Success" has perhaps curiously been flight safety's biggest enemy, the temptation being to "fine-tune" expensive programs and standards on the back of a superb historical record, (forgetting how that record was achieved).
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Old 25th Jun 2009, 04:16
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When introduced, the 320 then 330/340 series required a new understanding of how flight controls and automation worked - the airplane is obscure and confusing only if a student was offered barebones groundschool and eight simulator sessions before flying the airplane under supervision.
That's exactley what I mean, Automation stands for a lot of comfort, but when it quits, You're in front of a somtimes very complex situation and reduced training, for sure is the wrong answer.

The machine-human interface is not realy the best, I see that from the humans perspective.

My regards.
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Old 25th Jun 2009, 04:28
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As the pingers have a limited duration and it generally takes time to get the kit to detect / recover them to the scene, would it not be sensible to defer their start for a week or so?
Since the beacon only weighs 200 grams including the lithium battery, I say double or triple the battery size instead?
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Old 25th Jun 2009, 05:09
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airliners = drones times 10

I like that finally this thread is deviating away from speculation on salvage and systems faults...
The way I see it the only major cost cutting airlines can achieve in the foreseeable future is from crew cost and training cost.
Look - a drone can stay airborne for almost 48h depending on mission profile (that normally is much more complicated than flying A to B) and the guy/guys who fly it can get up, go to canteen, take a crap, take a siesta or even call the boss if things start getting out of hand... Isn't it beautiful?!
If in 10 years time the SLF is told they can fly for a third of the price of what they are paying now but in a robot driven a/c with A specialist (called PILOT) who is on board only for the never occurring need to do a hard reset of some equipment?!
Of course above para is a bit in line with H.G. Wells.
But... Are we sure?
Boeing and Airbus keep telling everybody that the price tag goes up because they are selling safer and better a/c that can be flown by CPL holders, albeit for the time being only from the RHS... Soon (I hear rumors) OPC/LPC might be done only once a year, but crew might have to be send to the sim for extra training... Who in their right mind will waste extra money on extra sim?! Once regulators give up the fight, recurrent training will be halved and this is not a H.G. Wells scenario.
To come back to experience levels of the Playstation Generation. The only way I see it is MFF. Put pressure on the young ones, so the keener ones make it faster up the ladder. Not on the Captain, that frequently has to put up with the unbelievable pressure of combining inexperienced crew with bad SOPs, commercial issues etc... Even more so if he wants to give something for free to the young guys!
I also heard a rumor that on this particular flight, AF447, the Captain might have come under pressure to depart on time with the usual "BITE test ok" bulshiv due to the presence of some big shots (God bless their souls) up front in biz class...
So I am asking myself once again why and how did they got themselves in the kind of bad wx that all of us normally avoid by 20 nm at least...

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Old 25th Jun 2009, 05:48
  #2277 (permalink)  
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Originally Posted by MostlyHarmless
Back to the FDR/CVRs. As the pingers have a limited duration and it generally takes time to get the kit to detect / recover them to the scene, would it not be sensible to defer their start for a week or so?
That would be an added technical complication although it does have merit. We used to have PLB with a battery life of about 12 hours IIRC. We were taught to anticipate the time for SAR to reach the area.

There will certainly be a re-evaluation of FDR etc. Will they be ejectable? Is their purpose to mark the crash site as well as record flight conditions?

Maybe there should be a 3rd simple acoustic crash locator beacon.
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Old 25th Jun 2009, 06:33
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egg and chicken

a) 341115 - PROBE-PITOT 1+2/2+3/1+3
279334 - FCPC2(2CE2)/WRG: ADIRU1 BUS ADR1-2 TO FCPC2


B) 279334 - FCPC2(2CE2)/WRG: ADIRU1 BUS ADR1-2 TO FCPC2
341115 - PROBE-PITOT 1+2/2+3/1+3

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Old 25th Jun 2009, 06:45
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Plans for Phase 2 of CVR/FDR Search

"Air France 447 Search Effort: Phase II Fact Sheet
June 24, 2009
C & C Technologies, Inc. (C & C) has received inquiries regarding our discussions with the French BEA on the second phase of the AF447 search effort.

The following information may help minimize communication errors:

1) Pinger Life: Dukane, the AF447 pinger manufacturer, has confirmed that the pingers may only last a day or so longer than the specified thirty days. Unlike regular flashlight batteries that fade out slowly, the battery technology used in the pingers will hold its voltage for the thirty days, and then quickly collapse along with the transmitted signal.

2) Contact by BEA: The French BEA has contacted C & C by phone and e-mail regarding use of C & C's 4,500 meter (15,000 feet) rated autonomous underwater vehicle (AUV) to perform a sonar search for the flight recorders. C & C has two 250 foot (76 meter) ships near the crash area equipped with state-of-theart AUV systems. However, the AUVs on those vessels are only rated for 3,000 meters (10,000 feet), and the wreck area approaches 4,500 meters. If the pingers are not found by the end of June, French authorities may ask C & C to send its 4,500 meter rated AUV to Brazil to search the mountainous underwater terrain.

3) Comments Regarding BEA's Actions: While the first phase of the search for the flight recorders continues, the BEA is making contingency plans for a second phase. Tapping C & C's world-renowned deepwater AUV search capability indicates the French authorities' commitment to locate the recorders and solve the mystery. Given the complexity of the situation, the BEA is making all the right moves.

4) AUV Description: Like the unmanned drone aircraft used by the military, AUVs are unmanned, untethered, computer controlled underwater vehicles. C & C's 4,500 meter rated vehicle is capable of searching large areas while flying at a constant height off the ocean bottom at four knots for two days at a time before returning to the surface to refuel. ..."

Lafayette Company Assists in AirFrance Efforts
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Old 25th Jun 2009, 07:46
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Originally Posted by PJ2
So. Do you believe the rumour or are you posting it here to see if others do?
- does this mean that someone (Swish266??) has information on the a/c tech state at dispatch? Please share it, Swish.
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