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AF447

Old 5th Aug 2009, 15:22
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qantas

The Air Caraïbe and the Qantas flights tried to reset their master flight computer in the hope to regain the normal law for the rest of the flight (Qantas was advised by the ground maintenance/technical center).
In the Qantas flight episode the a/c left normal law only when PRIM 1 was reset after the crew turned it off and PRIM 2 became master.

Actually the crew was trying to end the uncommanded pitch down events that maybe were happening because the a/c didn't change to alternate law as it should.
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Old 5th Aug 2009, 16:04
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Qantas, PRIM reset, erratic airspeeds & altitude

About PRIM1 & PRIM2 PRIM master changed from PRIM 1 to PRIM 2 between the two pich down events. PRIM master changed from PRIM 2 to PRIM 1 after the 2nd pich down event. About PRIM3, after the 2nd pich down The flight crew reported that, after returning the aircraft to 37,000 ft, they commenced actions to deal with multiple ECAM messages. They completed the required action to deal with the first message (NAV IR1 FAULT) by switching the captain’s ATT HEADING switch from the NORM position to CAPT ON 3 position, and then cleared that message. The next message was PRIM 3 FAULT. The crew completed the required action by selecting the PRIM 3 off, waiting 5 seconds and then selecting it on again. .../...
During one of the conversations, maintenance watch suggested that the crew could consider switching PRIM 3 off, and this action was carried out. This action did not appear to have any effect on the scrolling ECAM messages, or the erratic airspeed and altitude information.
----------------------------------
hence you are right augustusjeremy, there was already an ECAM message indicating a PRIM3 FAULT when this latter was reset. I am surprised to read that the Qantas flight had also erratic airspeeds & altitude information ? Jeff
PS) the Air Caraïbe PRIM reset:

PPS) Stall warnings are a typical signature of unreliable airspeeds events (Airbus):
http://henrimarnetcornus.20minutes-b.../196453185.jpg

Last edited by Hyperveloce; 5th Aug 2009 at 18:52.
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Old 6th Aug 2009, 03:15
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Back to stall handling...

Personally a lot of the comment and opinion on a good few pages recently, makes me 1) worried;
2) think that:

a) The bigger picture is how much 'real life', 'real stall' experience the handling pilot has... it sounds like a stall or an approach to stall warning to some airline pilots is a rare thing - frightening. Isn't this almost de rigeur in sim training, many stalls, in all flight modes - and refreshed regularly as matter of course

b) the only time an approach to stall is really anything other than (initially) a light and progressive push on the stick, is late in the approach. At any other sensible altitude, either totally ignoring stall approach warning or the obverse - loads of power and a heavy nose-down response - seems unlike anything sensible or ordained.
Always, especially if in doubt, ease the stick forward straight away whilst checking immediately the std scan instruments.. and thrust.

c) With the momentum and energy of 200 tons, a slippery shape and at cruise speed, if thrust is as expected, surely nobody has ever had to whack the throttles open and pitch heavily nose down (the two are anyway to some extent counter balanced in the shorter term).

d) If an incipient approach to stall with 35,000' to play with, cannot be handled with a natural small pitch down in the first instance, without fear or fright, then that's not a safe aeroplane. So I presume it is, and plenty of cruise thrust-loss and climb at low thrust incipient stalls are thrown into the training - it must be 2nd nature to fractionally lower the nose immediately - but that's all for a good few seconds.

e) If turbulence, of a strong or severe nature is present it changes the whole picture.... barely mentioned in much of the recent discussion on imagined events and (re) actions to indications and warnings. But wherever you are in almost all dynamic phases of pitch, a buffet, stick shake or airspeed warning still should produce that natural reflection almost immediately, followed by heightened awareness of where the craft is in pitch, attitude and power and trim state. As was pointed out earlier, that was probably all Buffalo shaker required in reality and should have absolute 'programmed in' natural response, from first flight in a glider, a 152, countless sim flights & checks, right up to an A380 for real - if not, we are in serious trouble in the skies.

The big unknown is not so much the way the airspeed might have gone haywire over seconds or minutes - but the onset and if severe turbulence, the level, type and wavelength - was that a big factor. Something we can imagine, pontificate about but really just don't know - it could have been a very big factor, or not a factor at all.

My comments are really not pointed at the AF447 situation, more, why are we even discssuing what is/should be hard-wired as a stall approach response?
Because the a/p kicked out so unexpectedly?

That should be expected in severe turbulence and expectation implies high situational awareness (airspeed/picth/power/trim etc)
If not expected then we have a) a/p fault b) flight data fault. c) something has broken or you've hit something.

Sorry to drag this out... I'm left with a question.

How much manual handling sim-time and real flight-time is built up per thousand hours in heavy to severe turbulence conditions (i.e. when it would perhaps be expected the a/p would find itself on or beyond limts) ?
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Old 6th Aug 2009, 04:58
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HarryMann;
How much manual handling sim-time and real flight-time is built up per thousand hours in heavy to severe turbulence conditions (i.e. when it would perhaps be expected the a/p would find itself on or beyond limts) ?
A thousand hours is, for most major carrier transport pilots, about 12 to 18 months of "hard time" depending upon contracts. (Putting in 85hrs of hard time in a month for an airline pilot is risking high fatigue levels). A 330 captain on long haul operations may get 3 landings a month, perhaps 4, maybe 5 on rare occasions. Domestic crews will do 75 to 90 landings a month and about the same hard time.

From my own experience, almost all crews engage the autopilot above 3000ft. Very few fly to 10,000ft/FL100 and almost nobody flies to cruise altitude. Disconnection can occur at about the same altitude on approach - 3000ft, but most crews disconnect below 1000ft, and many at around 400ft.

At 1500ft on approach, an airliner is just over two minutes to touchdown.

Out of a typical flight, I would estimate the first five minutes and the last 3 minutes are hand-flown, the usual exceptions applying.

If the typical number of landings applies per month, a long-haul crew member may be getting, at the most, 30 minutes of hand-flying per month or about 6, perhaps 9 hours of hand-flying during the 12 to 18 month period. A domestic pilot would be doing the number of landings per month times about 7 minutes but it's more difficult to estimate for short-haul.

There is NO hand-flying taught or encouraged in the simulator except for the requisite steep turns and approaches to stall on an initial aircraft checkout. There is NO standby instrument practise and, very rarely, we did a raw data, (no flight directors) hand-flown, (including manual thrust levers), ILS. These approaches are usually between a bit ropey and a go-around but some are spectacularly, beautifully hand-flown with the loc/g-s or airspeed "painted" on the gauge face. Over the years, hand-flying was discouraged more and more and finally the authority to disconnect was removed from the FCOM except in circumstances where workload was low, (no traffic, no weather).

I have never in 35 years of sim work, carried an airliner into the stall. Such work was and should be test-pilot work as no airline pilot ever expected to have to deal with a full stall and certainly not a spin in a heavy transport.

With four, likely five recent accidents in which the crew lost control and stalled their aircraft resulting in a fatal accident, perhaps times and expectations and reasons for studying the full stall, have changed.

Within limits, we never had altitude restrictions within which we had to recover and we always watched for the secondary stall from pulling to hard or not enough nose-down. Jet Upset maneuvers were never done nor trained. We practised EGPWS and TCAS escape maneuvers.

I don't know how much of this reflects others' experience.

Last edited by PJ2; 6th Aug 2009 at 05:11.
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Old 6th Aug 2009, 12:10
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PJ2

Thankyou.

You're not the one in the firing-line, but I would then like to ask generally, how is the handing back of an aircraft to manual flight in what may inevitably be a 'less than trained for' state - condoned as acceptable - in the larger scheme of things.

I have obviously lost the plot in the last 30 years making these seemingly simple (and silly?) deductions of 'a training and skills maintenance system fit for likely purpose, '... or the industry has lost the plot - in one crucial area - if not more?

An accident that may not be thought to be in this category - AA587 wake turbulence handling - trained for specifically - but (allegedly) improperly.
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Old 6th Aug 2009, 16:50
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HarryMann;
how is the handing back of an aircraft to manual flight in what may inevitably be a 'less than trained for' state - condoned as acceptable - in the larger scheme of things.
I hope others who have perhaps left the thread but visit it to see what's changed, might offer their views on this subtle but important question.

The intoxication with automation largely through the substantial crew-cost-reductions have moved the industry thinking a very long way away from "focus on skills" since I joined in the early '70's. The focus is on "managing" the airplane, not flying it. The philosophy works almost all the time because automation is very good at "normal" and is, in my view, a tremendous safety enhancement. But like designing wings, engines and other bits, any "improvement" always comes with a cost, a compromise which is almost always obvious and economically acceptable in the trade. In my view, it is "the intoxication" that has blinded the usual awareness of those costs when the discussion turns to automation. I remember very well the introduction of the 767 with just two pilots. Like the Douglas Company's DC8, the "new" 767 cockpit design would have long seat rails so the First Officer could "travel" back to the panel and manage the fuel and whatever else was back there. In the case of the DC8 I guess the regulator (wisely in my view) didn't go for a two-pilot, four-engine airliner in the 60's but the 767 arrived with an Observer Seat and not a Second Officer seat.

When the 320 was introduced, veteran pilots raised on cables and pulleys saw the automation compromise instantly and began cautioning against loss of situational awareness, loss of the third set of eyes and something new that they called "mode confusion". I have many articles from AW&ST on this phenomena as I think it was an historical moment in aviation that would have consequences - it wasn't that it was hard to see - it was because of the wholesale, unquestioning adoption of automation as a panacea to cost, the arrival of which came during yet another mini-recession and "trouble at the airlines". It also came during the implementation of de-regulation in the US, where "cost-advantage" drove many agendas. "Intoxication" is not too light a term when looking back.

At the time, nobody knew anything about the airplane and the instructors were literally 24hrs ahead of the students. I think the introduction was successful in large part because of the flying and thinking skills of the pilots at the time. When the 320 began doing something we didn't understand, we simply disconnected and hand flew it until we sorted it out - not a big deal.

I don't think the same circumstances would be quite as possible today. Too many pilots are afraid to disconnect the autoflight/autothrust systems and fly just for the fun of it and managements are fearful of this very fact and my experience has been that instead of training, after an all-weather approach or other handling incident they tighten the reins and prohibit manual-flying even more. The philosophy has a logical outcome and that is a loss of skill accompanied of course by the subtle loss of confidence in one's ability to take over.

Given the propensity these days for many, and certainly the media, to instantly come to extreme conclusions more out of habit than thinking, I must caution that these are very black-and-white pictures that are being painted in this and other posts of mine; - the reality is far, far more subtle than is being stated. But these posts, already too long, would be a book and a very dry one at that, which no one would ever read. The industry is NOT falling apart at the seams but instead is coming to terms with the same kinds of changes pilots and managements did when the piston era yielded to the jet era beginning around 1954 or so, a phenomena that most pilots saw and commented about from 1988 on. These are observations made by many in the industry at the time, and today. "Listening" however, is a lost art. "I'll see it when I believe it" is the outcome.

The question you ask is, "Is the industry concerned about Loss of Control, (LoC)?" and I would submit, "no, not yet" as a tentative response. But it should be on their radar, given the four, likely five recent stalling accidents by crews ranging from veteran to relatively inexperienced.

My own response would be somewhat "actuarial" as opposed to ideological. "The loss of skill is condoned" by airline managements by virtue of the changed focus of initial and recurrent training regimes towards "managing the cockpit" instead of flying the airplane, and by virtue of the strong, overwhelming success of automation's introduction and presence.

As always, an informed, (through the heavy use of collected flight data, LOSA programs and crew reports) and measured response is indicated, "a bow towards manual flight with a view to re-familiarization and re-building", not a wholesale revising of priorities, would be something to consider as a viable response. It is as much attitude as it is foundational skills that has changed.
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Old 6th Aug 2009, 17:15
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re: automation

PJ2:

Although I work in the IT industry which has nothing to do
with aviation your comments on automation and blind reliance on the same, struck a chord within me.
I see automation all the time in my industry. We call it the "lights out" environment where most, if not all, the day-to-day functioning of a data center is automated. Management loves it because it allows them to "cut costs" and eliminate positions or, worse, outsource.
Automation is good. When used wisely. It is very bad when blind reliance is enacted. I have all too often seen automation "mask" some very undesirable problems. With very ugly consequences.
To me it is, and always will be, a matter of knowing what lies behind the automation ie, what is the automation doing and how can I ascertain if what being automated is indeed being correctly automated. It's not an easy task by any sense of the imagination. In computer terms I liken it to the differences between MS Windows and operating systems like VMS, Linux and Unix. Windows, as we all know, is more or less a point-n-click world. VMS, Linux, Unix and MVS (IBM) are command line interfaces. Such interfaces allow you to access the very guts of the operating system, should you feel so inclinded. Windows does not for the most part. But, and this is a big but, if you do know what lies behind the point-n-click world then you are in a much better position to control that environment. Most people nowadays in the IT world, have no idea what lies behind their GUI environments. To know what is going on within a given system, at all times, without blind reliance on automation and/or point-n-click, brings one a much better understanding of the environment then one without such knowledge. And allows one to be much more "aware" of what is going on in a given system.
I think some of this can be extrapolated to some aspects of aviation, specifically to the fbw environment. Perhaps I'm incorrect in this as I am not involved in aviation but I think the underlying principles of my assertion are valid.
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Old 6th Aug 2009, 19:08
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rgbrock1;
The notion of "understanding" has changed according to economic and therefore "cultural" needs from mere mechanical how-to, to knowing one's role but not knowing what is underneath the required adaptions we all have made. That change began around 1970 when the post-war economy began to be dismantled.

It is inconvenient to commerce to have, seek or require understanding beyond what is needed to be known about one's small participative-footprint within the larger system. The notion of "NTK" - Need To Know is an adaptive term, perhaps a euphemism, has been applied to aircraft since the introduction of the 320. When many of us began flying, we had to be able, from memory, to draw aircraft systems, draw complex terminal areas and know what made an aircraft tick. We had to know aerodynamics, high-altitude flight and how to draw then analyze weather systems. I knew captains who would draw the entire route weather, analyzing frontal systems in 3 dimensions and where the icing was to be expected. No longer. "Dumbing Down" is the label applied to what has happened since 1970 or so but because today we have "normalized the deviance" we accept that people can "talk on the surface" ad nauseum and be taken seriously as knowledgeable when in fact "flying" has become "managing" a machine.

Therefore, whether it is something as pervasive and institutionalized as a democracy, or whether the environment is an aircraft cockpit, one needs certain tiny, targeted pieces of information to function within the narrowly-defined band of competency, the exceedance of which is not encouraged in either environment.

Whether one comprehends what one is doing with a click of the mouse in a Windows environment, (especially in Vista ) or what is going on underneath the push of the ALT knob on the FCU of a 320/330/340/380 type is immaterial to the task at hand. In such an environment, one's knowledge is limited to, and is, "outcome driven", and is not "needs (comprehension) driven".

We can't change culture of course but we can, through philosophical approaches, comprehend the underlying assumptions of seemingly "stupid" behaviours and alter and otherwise tweak slightly these behaviours towards original-but-masked goals, in this specific case, towards flight safety.
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Old 6th Aug 2009, 21:14
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PJ2:
Excellent analyses. In aviation, technology grows in leaps and bounds, but as far as the good old human interface is concerned,we are forever reinventing the old wheel. Favourite long time quote-"Man has oft more need to be reminded than informed". Thus history just keeps on repeating itself when we read the Human Factors/CRM/(aka Airmanship) aspects of these accident reports.

Re:Manual flying: This subject has been covered ad nauseam in previous threads. But the current thread has brought the issue back into the spotlight. Well, another old favourite (courtesy of Andy Capp)-"The older I get, the better I was".Our skills inevitably degrade with age and lack of practice. But putting macho aspects aside, the fact is-todays aircraft are designed to be flown/managed with the automatics. Todays ATC/RVSM/RNP environment has no place for inserting (rusty) manual flying, (no matter what 411A thinks!) and the proof lies in the FDAP program that many airlines practice (quite rightly) to trap the unwary, the rusty, the cowboys.

Quite rightly so; I don't know about you,but when I am riding down the back, I don't want to be subjected to some wild ride while the guy up front tries to polish up his manual flying skills (not) , while the PM is working like a one-armed paper hangar doing config changes & RT/MCP/MCDU work, as well as frequency changes, at the same time as trying to monitor the Ace's not-so-hot flying on a dark night on a typical European or elsewhere RNAV SID or STAR.Don't laugh;I have seen it on quite a few occasions while sitting on the jumpseat as augmenting Captain.

Where I do agree with you 100 per cent is the failure to address these issues in the simulator. We should be doing far more raw data manual flying in the sim on recurrent training (maybe not on base checks;jeopardy involved here); if you can't hack it, serious questions need to be asked; and yet, as you say, this is not happening! Apparently, on the 777, some operators do the V1 cut in the sim b/checks with the TAC (Thrust Assymetry Compensator) on! Don't even have to think too hard about which rudder to push! Where is the sense in that? A big wakeup call is needed. Automation works most of the time,but you better be ready when the gremlins strike.
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Old 7th Aug 2009, 13:54
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Final trajectory, debris distribution, currents

Hi there. I know that the question was largely discussed, and I remember Takata's contributions. When we use the NOAA/OSCAR currents which are observational (SHOM currents are predictions, the result of a 3D model), it seems that these data are able to describe the debris drift between the 6th of June and the 20th of June and the rotation of the current direction from north north east to north north west. The NOAA/OSCAR time series (not the current maps) show that the current speed nearly doubled between the two periods June 1 - June 6 and June 6 - June 9 (from 0.125 to 0.215 m/s): the drift range between these two period should be roughtly similar. This would give an area for the debris on June the 1st marked by the interrogation marks. Would it suggest that the initial small departure of 3NM to the west of the SALPO-TASIL route (seen on the last known positional ACARS at 02:10Z) has become a large turn to the west ? Maybe not a U-turn but a substantial route alteration (>90°) ?
Jeff

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Old 7th Aug 2009, 15:45
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Jeff, my feeling based on the drift was that there was a deviation to the west of the track. I have always felt, based on the search grids June 2-5, if there was a deviation to the east of the track, the search would have discovered the debris a lot sooner. I won't speak for takata as to whether he eventually abandoned his idea that the plane did a 180 or attempted to.
_______________
I am both a bit surprised and a bit disconcerted that there is no news of the sonar having picked up any targets worthy of investigation by the mini-subs. The sonar sweeps probably have covered nearly half of the area they intended to sweep at this point, and one would expect they would start with the area they thought the plane most likely impacted the sea. If that is the case, they would now be moving the grids significantly greater distances to the north of the last reported position, and west of the track. Even if the boxes are never retrieved, the impact point can be critical to several theories for how and when the plane came to fall into the sea.
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Old 7th Aug 2009, 20:42
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Fox News has identified 12 US Airline loss of airspeed incidents

Probe Finds Airspeed Sensors Failed on at Least 12 U.S. Flights

This suggests that loss of airspeed indication alone should not have brought down AF447. There must have been some other relatively unique factors involved. I believe this lends weight to PJ2's comments along this line. Probe icing is not enough by itself to account for the problem.

I might wonder if the relative lack of light outside the cockpit made it impossible during heavy turbulence to maintain proper attitude. Remarks here indicate that in severe turbulence, when you may need it the most, attitude indication, and indeed all the instruments, become very difficult to read. Would that combination be sufficient to account for AF447?

This also suggests to me that there has been a bad pitot probe problem for quite some time, particularly with the Thales probes. Thales is already hedging itself with the whine that they built their probes to AirBus specifications. I see some blame shifting and finger pointing rather than efforts to fix a bad situation. I also see some indication that this problem may have been covered up for quite some time now.

It's expensive to replace these probes unless the public learns enough to demand it. With the relatively low caps on liability for deaths that airlines face there is the specter of a lost plane here and there is a simple "business expense". The plane itself costs more than the payouts for the deaths, I believe. That gives me pause to think about flying, as if the TSA hassles are not enough for that.

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Old 8th Aug 2009, 12:06
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On the French speaking web site, they have published the details of an incident which occurred "a few months before" AF447. In that case, maintenance have found that the three probes had the water drainage holes blocked. My question is again a naive one: in such a case, the problem is considered to be solved once the drains are cleared and the pipes flushed (as per the Airbus procedure), OR is there a mechanism to at least trigger more frequent inspections? For sure if maintenance is done correctly, then it should NOT be normal to find all 3 probes with the drains blocked?
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Old 8th Aug 2009, 12:35
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Pitot design ass u mptions?

There appears to be no laws of dynamic similarity that would make a scaling up of the whole pitot probe inaccurate and I'm stretching myself to think of a problem with a 50 or 100% bore increase.
Airborne contaminants are generally small and large ones less likely to be homegeneously distributed, e.g. windborne detritus. Meaninga larger one might be more prone to detrital blocking but not 2 or all 3. Neither would one be as prone to complete blockage.

Obviously there is an optimum scale for a pitot probe, but has it been chosen too small.. key criteria to be considered are also inspection, cleaning, repair and corrosion (relative blocking ability)

I also can't see why the entry bore cannot be modelled smaller than the main bore and drain, as long as full pressure recovery is achieved, Q will be measured when V=0 at the transducer face. This could prevent larger scale detritus entering at all...

However, the manufacturers I accept, know a damn sight more than myself - even Thales - but are maybe working to a poorly conceived set of specifications (e.g. size, cost etc) that may indeed be quite historical and never reviewed for sensibility in many, many years...
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Old 8th Aug 2009, 13:28
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Originally Posted by pax2908
On the French speaking web site, they have published the details of an incident which occurred "a few months before" AF447. In that case, maintenance have found that the three probes had the water drainage holes blocked. My question is again a naive one: in such a case, the problem is considered to be solved once the drains are cleared and the pipes flushed (as per the Airbus procedure), OR is there a mechanism to at least trigger more frequent inspections? For sure if maintenance is done correctly, then it should NOT be normal to find all 3 probes with the drains blocked?
I think we can find an AESA air worthiness directive from 2003 whose purpose is to increase the maintenance frequency on the Pitot probes. Another AESA paper describes manufacturing problems on the drain of certain AA probes resulting in a rapid obstruction, poor water drainage and poor performances in case of heavy rains or icing conditions (even if you have an efficient heater). Maybe we see now the difficult aging of these AA probes. But whatever, when the French Air Force lost a Mirage 2000 five years ago, the military did not wait for a similar problem to reoccur: the AF conducted a large study on its entire Mirage 2000 fleet to get complete statistics over a period of time, to analyze the risk and its evolution, and to adapt the maintenance. Has it been done on these airliners ? Jeff
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Old 8th Aug 2009, 16:51
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Re. to HV (post# 4154). Following your suggestion I was able to find a few ADs which seem relevant.

The most recent (2003-148) is for A300/A310 and Thales AA probes with low serial numbers; it refers to a manufacturing defect of the drain hole; and requires to perform the Thales procedure to clean/repair the probes. This AD seems very similar to two ADs isssued in November 2002 applying to Thales AA probes with s/n lower than 4760 (2002-586 for A320, and 2002-594 for A330/A340).

These ADs are in response to airspeed discrepancies reported by "an A320 operator".

I was not able to find, in these ADs, a direct reference to the increase in maintenance frequency. Also I was not able to find anything more recent from the EASA web site. I do believe that Airbus has been following this closely.
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Old 8th Aug 2009, 17:33
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good spark

IMO the answer has been available for some years, and lifting the 'rug' merely emphasizes what needs to happen. Whether its static electricity, dissimilar metals, or salt corrosion, the Pitots are being changed. The issue isn't pitots, it's recognition and response. It has become painfully obvious where on the list of priorities Aviation 'safety' reposes. Feigning mystery and taking years to act has become de rigeur.
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Old 8th Aug 2009, 18:45
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PJ2
Is it just possible that the automation of aircraft has contributed to;
a. lower costs thereby keeping the aviation industry afloat and
b. improved overall safety.

Could it be that it is inevitable that there will be aircraft crashes when systems fail and the controls are put in the hands of pilots trained as managers rather than pilots.
This could be the 'cost' of sustaining the industry and maintaining an overall safer flying environment.

It may just be that we get far less disasters using computer systems to fly the airctaft than if we relied only on live pilots - however well trained and experienced.
Expecting any pilot to cope with situations that are outside of the ability of the computer systems might just be asking too much.

In a situation where an aircraft knowingly entered weather for which the aircraft was not designed maybe one cannot question the systems if they fail.

Don't shoot me, I am being Devils advocate with these questions in order to suggest alternatives - we seem to be stuck on 'real pilots are better' & 'bring back the old days'
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Old 8th Aug 2009, 20:21
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funfly;
Don't shoot me, I am being Devils advocate with these questions in order to suggest alternatives - we seem to be stuck on 'real pilots are better' & 'bring back the old days'
On the contrary the point you raise is an excellent one. No "Devil's Advocacy" here - what you say is the truth. It is a long acknowledged fact that automation has dramatically reduced industry costs and enhanced flight safety. The weight savings in hydraulics and other mechanical solutions to flight controls and landing gear operation alone on the A320 design were significant. The reliability and accuracy of automation is nothing short of spectacular and is nowhere more beautifully demonstrated than on a Category IIIb ILS autoland approach in RVR600 conditions, (forward visibility 600 feet). The safety factor has increased exponentially too, with automated peripherals such as TCAS II, EGPWS, FANS and ACARS all of which have prevented untold numbers of fatalties. Don Bateman's (of Honeywell) invention, GPWS has prevented untold numbers of CFIT accidents.

In short, automation has been a hugely positive net change for commercial aviation. Computerization has made exponential changes in flight safety in related areas through ATC capabilities, (radar & transponders, predictive tracking) and weather prediction and modelling and disemination of this information rapidly and widely through the internet, (Like many crews could, I used to start my flight planning in the uninterrupted calm of the hotel room some four hours before departure, downloading the flight plan onto the laptop and studying the weather etc). Mechanical and technical reliability of aircraft have made system and engine issues almost a thing of the past. Engine shutdowns are rare compared to the piston era where arriving from an overseas flight on all four was an event.

Aircraft instrumentation accuracy, the introduction of flight management guidance computers, satellite communications all have contributed to reducing vertical, lateral and longitudinal separation standards, putting more airplanes into the sky safely. The introducion of RVSM standards reducing vertical separation from 2000ft above FL290 to 1000ft literally doubled available airspace both domestically and over the ocean.

Automation can mitigate the effects of fatigue because it doesn't get distracted, lose situational awareness or suffer from any of the other very elementary human frailties such as vertigo or fear. Automation is a fine and "loyal" servant, used wisely and intelligently.

Except for the kind of respect that this profession used to (deservedly) garner but has been lost by the processes herein described, the call isn't for a "return" to the old days - not at all. In fact, were we to do that under the watch of present industry leaders and regulators I strongly suspect the accident rate would skyrocket immediately. It's hypothetical however and as such is a meaningless argument - we're not going back.

Automation has one major, huge fault however and we all know what it is. That fault is the subject of the entire thrust behind this dialogue - computers and automation is dumber than a bag of hammers - it is GIGO, all the way down. Automation will fly an airliner smoothly, accurately, beautifully, straight into the ground, (and has) or will, if pilots permit, stall the aircraft, even the Airbus.

The secondary effects of automation is loss of situational awareness and loss of flying and thinking skills. Loss of instrument scan may be a tertiary effect.

This conversation is really about "support" for the best flight safety enhancement the industry has ever had - a skilled, trained and experience airline pilot. That enhancement is the least expensive of all the changes which have occurred to take flight safety where it has gone since the 50's.

"Support" means respect for the capabilities and contributions of a professional airline pilot. "Respect" means paying a wage that one can raise a family on, buy a house on, retire on. You aready know that Captain Sullenberger (and every pilot at US Airways, United and a few other major carriers) don't have pensions even though they paid into them.

Support means training intelligently, effectively, using flight data programs and LOSA information upon which to base curriculae and not just training to pass the ride and tick the box. That requires infrastructure, staffing, and a longer-term vision than quarterly results. That means that some things which do not directly produce "profit" must nevertheless be supported and not be targeted under the constant drive to cut costs where "lack of production" is perceived. I have seen it written and heard it said from the executive levels of airlines, sometimes couched in euphemisms, sometimes not, that pilot augmentation for long-haul operations is merely so much union feather-bedding. An enlightened use of human factors knowledge in combination with the substantial science already available on circadian rhythms, just for starters, is needed. When the FAA comes to actually believe there is need for change, we know that the problem is serious and has been for decades and decades. In Canada, the problem remains unrecognized and undiscussed except among flight safety groups and advocates. Despite their words on flight safety, IATA has in the past been one of the more vocal groups speaking/lobbying against any changes in flight time and duty day regulations.

Support means acknowledging that, just like other professions, it takes time to grow experience and that one does not just pick such things from trees.

"Experience" means time, but the pipeline is drying up. Young people don't want to be "airline pilots" these days for all the obvious reasons that are both succinctly and clearly expressed here by many, the finest expression coming from Captain Sullenberger before Congress in February.

Young pilots need to be shown how it was and how it ought to be. Ms. Shaw likely never understood the disadvantages of the lack of such support and guidance because to those who are starting out, everything is "normal". Those who have lived the career for some time, know (and knew) better.

This is a tall order which almost certainly will never be filled until industry itself recognizes the problem. At present, there is "no elephant in the living room" and most managements are "satisficed".

We cannot say if loss of control accidents will trend upwards or not. Preventative strategies which produce "nothing" as a successful result, (ie, no incidents, no accidents) are extremely difficult to implement and defend when the MBAs come looking for where to cut costs and especially where the executive levels don't comprehend how flight safety work is done.

Out of experience however, we can say that given fertile ground as described and not just incidental opportunity where the holes line up, untoward trends in aviation will continue and may increase.

These aren't wholesale, massive changes being called for. They are a change in stance - The belief that an airline pilot can be made by giving the candidate 250hrs of simulator and then putting them in the right seat of an A320 or B747 and expecting that the captain will not be alone should something serious occur, is the lack of support being discussed here. It is money, nothing else, that drives this kind of thinking.

So your question is a good one I think. It needs far more examination and discussion than one little posted response. It is at the heart of the important questions, "wither aviation, wither the profession of 'airline pilots', wither flight safety?".
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Old 8th Aug 2009, 23:17
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PJ2

Wow!

What a shame a collection of such erudite responses aren't going to be published in an Airline Aviation Safety Journal - or would there be no-one of any influence subscribing to their mailing lists within the industry these days?
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