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Old 9th Jul 2009, 17:34
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One question out there for anyone who has done air-water collision investigation in the past is what impact do you think that wave height would have on the damage found in the crash debris? The A330 fuselage is about 20 ft wide, so if waves were 10 ft tall (and I would expect them to be substantially higher), they would seem to be quite significance on the forms of damage we would expect to see. But maybe someone has experience with this?
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Old 9th Jul 2009, 18:10
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Lemurian's French Soundbite

Qu'avez-vous vraiment changé depuis le très critique rapport Colin sur la sécurité aérienne ?

Je suis fier du rapport Colin, diffusé à tous les navigants de la compagnie, et qui montre que chez nous, il n'y a pas de tabous en matière de sécurité. En octobre 2005, nous avions confié à trois commandants de bord instructeurs d'Air France une mission d'analyse portant sur l'organisation et le fonctionnement de nos opérations aériennes. Depuis, il faut savoir que les recommandations de ce rapport ont été mises en œuvre dans tous les domaines : règles opérationnelles, organisation et sécurité des vols, formation des personnels navigants, exploitation et maintenance au sol.

Here's a human attempt at rendering the lad's statement, Lemurian:

What have you really changed since the highly critical Colin report on air safety?

I'm proud of the Colin report that was distributed to all our flight crews, and it shows that, in our company, there are no limits when it comes to safety. In October 2005, we asked three AF captain/instructors to do a study of the set-up and operation of our flight operations. You should know that since then, the recommendations from that study were applied across the board: operating procedures, flight safety & organization, flight crew training, ground maintenance and operations.

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Old 9th Jul 2009, 18:25
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NASA to trial oceanic forecasting

Here comes the cavalry....

Full story at

NASA Research To Help Aircraft Avoid Ocean Storms, Turbulence

Goal Is To Identify Rapidly Intensifying Storms

NASA is funding the development of a prototype system to provide aircraft with updates about severe storms and turbulence as they fly across remote ocean regions.
Scientists at the National Center for Atmospheric Research (NCAR) in Boulder, Colo., in partnership with colleagues at the University of Wisconsin, are developing a system that combines satellite data and computer weather models with cutting-edge artificial intelligence techniques. The goal is to identify and predict rapidly evolving storms and other potential areas of turbulence.
"Turbulence is the leading cause of injuries in commercial aviation," said John Haynes, program manager in the Earth Science Division's Applied Sciences Program at NASA Headquarters in Washington. "This new work to detect the likelihood of turbulence associated with oceanic storms using key space-based indicators is of crucial importance to pilots."
The system is designed to help guide pilots away from intense weather. A variety of NASA spacecraft observations are being used in the project, including data from NASA's Terra, Aqua, Tropical Rainfall Measuring Mission, CloudSat and CALIPSO satellites.

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Old 9th Jul 2009, 18:29
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welcome to the 21st Century!

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Old 9th Jul 2009, 18:48
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Latest from Flight

Flight has more info from the interview of AF CEO Pierre-Henri Gourgeon, which is much more interesting that than the bits that have been cited here earlier.

[AF559] crossed a turbulent area that had not been detected on weather radar and, as a result, increased the sensitivity - subsequently avoiding a "much worse" area of turbulence. ... The crew initially chose to deviate 20nm to the west but the radar then showed an extensive squall line which led them to deviate to the east by 70-80nm.
See Air France reviewing weather-radar use after AF447 crash: CEO
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Old 9th Jul 2009, 18:54
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Or maybe this particular judge just isn't really a judge but an anxious anonymous person interested in making the Brasilians looking silly.
Reuters is probably part to this conspiracy.
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Old 9th Jul 2009, 19:04
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NASA to the rescue?

... combines satellite data and computer weather models with cutting-edge artificial intelligence techniques.
This is good stuff, but don't hold your breath waiting for it or you will turn blue and then several other colors while waiting. "Combine cutting-edge" in this context is code for "basic research". Basic research is good stuff, but optimistically it will take 5-7 years before it can become a product. NASA has been working on "Smart ATC" for some 10 years now and are doing good things; but I don't think a lot of it has made it into normal ATC usage yet.

But while this particular NASA plan will take a while to pay off, I'm sure there are very useful things that can be done immediately with not much more than a satcom modem, a laptop, and a little duct tape. A second generation version would build it into the ND. Pilots should probably get their unions to agitate for some quick solution like this, at least on long haul flights.
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Old 9th Jul 2009, 19:42
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Autopsy results (cont'd)

I'm no lawyer, but I just wanted to make a quick comment about that:
Everybody, but especially this supposed magistrate could know that the French police had four investigators present at the forensic examination of the 51 victims in Brazil.
These experts were mandated by the judge in charge of the French penal investigation. They are thus bound by professional secrecy (penal code, article 11) and cannot communicate directly any information to the BEA. If I'm not mistaken, only the French judge may decide to make their reports public.
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Old 9th Jul 2009, 19:49
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Snippets from an interview with the AF459 captain

This is from a weeks-old interview with the AF459 captain and copilots, who all wish to remain anonymous. The original is at Le Figaro - France : «J'ai traversé le pot au noir20 minutes après le vol AF447».


According to one of the two F/Os, “this cloud formation was hard to locate because there was no lightning.” AF459 made a 70nm detour while AF447, flying 20 minutes ahead, must have gone through that zone, the F/O added. However, his captain would not confirm that last point.

Pilot Error Unlikely
The AF459 flight crew noticed nothing unusual crossing the “black hole”. “Except for the cloud formation, flight conditions were normal and we heard nothing on the distress frequency. We also had no radio contact with AF447 before the accident, contrary to the rumor that has been going around for three weeks now.” Inflight, the captain had no knowledge of the disappearance of AF447. That part of the Atlantic is not covered by ATC frequencies that reach only 200 miles from the coast.

Approaching the Canary Isalnd, the AF459 captain established first contact with air traffic controllers. They asked him to make relay contact with AF447. “We radioed in vain on the distress frequency,” he said. “But we didn’t much worry about it because radio breakdowns on aircraft can happen. We also hoped another aircraft closer to its position might establish radio contact.”

The AF459 captain and crew first learned of the accident on arrival at CDG at 1135LT…The captain said human error was unlikely to explain the loss of AF447: “The preflight (=au depart) satellites photos were clear and any pilot knows how to use his radar.” If AF459 had managed to escape a particularly active cloud formation that was difficult to locate without increasing radar sensitivity, might AF447 have failed to increase it? “Sure, not everybody does that,” admits the AF459 captain.

Oddly, three weeks after the accident, the AF459 captain has not been interviewed by the BEA, which plans to publish its report at the end of the month. Contacted by Le Figaro, the BEA declined to comment on this point.
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Old 9th Jul 2009, 19:52
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I'm a little bit qualified to answer that one.


1/ Would make a controlled forced landing more gentle. Less friction/time. This is why seaplanes prefer a few ripples for take off. Nose down accident landing, with a nose into a wave face, almost infinite pressure loading on surfaces normal to that wave. Liquids are not compressible. Tail down 'landing' - waves wouldn't do much other than pull the nose down, perhaps violently (wave lengths and heights being just 'right')

2/ On floating bits of the aircraft. Any piece of debris with a Specific Gravity greater than 1, attached to a sufficiently large corresponding part with SG less than 1 will float. Wave action (cylindrical flow aligned normal to the wave peak) will have an effect on the piece. If the piece presents itself in the same direction to each wave (because it's shape vs wind/wave dictates that - a tall bit above the surface will keep that piece facing in the same direction wrt apparent wind angle, and or old wave train direction) then there will be repeated strains in a particular plane. If not, then there will be multiidirectional strains.

3/ If SG of the whole piece is less than 1, really very little damage through wave action.

4/ This applies to clothed bodies too. The heavier part is below the water, the wavelets will continually tug at loose bits thereto attached.

5/ At any angle of approach to water with a significant vertical speed you can treat it as concrete. Nose impacts, wings bend, engines off and tail at the end of the chain.

ps. The usual 45 degree thing applies. Hit anything square on fast enough. Terminal. At 45 degrees you might get away with it. Any less and you should buy a lottery ticket.
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Old 9th Jul 2009, 20:04
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Gosh JuggleDan

If I'm not mistaken, only the French (investigating magistrate) may decide to make their reports public.
He'd better refer to his minister before opening his mouth on this one!

(For anyone unfamiliar with French Law, criminal investigations are headed by a magistrate. The idea is that, not being a police officer, s/he can evaluate evidence more objectively, thereby better protecting the suspect's rights. It also means that when the case reaches the prosecutor, the evidence and charges are neatly packaged and ready to serve in court. In the USA, police officers run the investigation independently and then move it directly to the prosecutor who sometimes grumbles when officers don't think in legalese.)
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Old 9th Jul 2009, 20:42
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Thank you for the translation Arthur Borges! If Mr Gourgeon, Chief Executive of Air France seems to be very happy with his company (some people never learn) the Chief Executive or Air France-KLM, Mr Spinetta, told the shareholders today:
"Air France ne prétend pas «avoir tout bien fait» et la sécurité de ses vols «a été prise en défaut», a dit jeudi le président d'Air France-KLM Jean-Cyril Spinetta, en évoquant les circonstances de l'accident du vol AF 447 entre Rio et Paris le 1er juin."
I translate before you (sorry!):
"Air France does not say it has done everything well, and it's Flight Safety has failed."
Seems to me the days of Mr Gourgeon as Chief Executive will not see autumn...
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Old 9th Jul 2009, 20:43
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NASA oceanic forecasting

This is good stuff, but don't hold your breath waiting for it or you will turn blue and then several other colors while waiting. "Combine cutting-edge" in this context is code for "basic research".
Very true, right on the "bleeding edge".... They'll be looking for partners to fund the move to production no doubt and this time they might get some from Collins, Honeywell, L3, et al. NASA themselves cannot take the development through to certification.

The base technology is there. Look at any Cirrus avionics fit - Garmin G1000 and Sirius/XM weather overlay provides most of what's needed for "phase 1" if the satellite data is available for the area in question. Storm tops and intensity would be a start. Forecasting CAT might be better off left to on-board Doppler for now (IMHO).


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Old 9th Jul 2009, 21:32
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Arthur Borges,

It would seem from the BEA report that the AF459 crew was interviewed prior to its publication. There is an extensive narrative of the deviation flown by this flight, and their communication with Atlantico in that regard.
LH507 preceded AF447 at ORARO by 20 minutes (or about 0143). LH507 deviated west by 10 NM. (This may be the flight that was providing AMDAR reports. If not, the flight with AMDAR preceded LH507 by 10 minutes.)

IB6024 was at ORARO 12 minutes after AF447. IB6024 deviated to the east by 30 NM.

AF459 initially chose to deviate west by 20 NM, but then deviated to the east by 70-80 NM. AF459 was at ORARO 37 minutes after AF447.

AF447, instructed to contact Atlantico at INTOL, establishes contact with Atlantico at 0133-0135. How likely is it AF447 overheard LH507's deviation west? From the radio communication transcript, there is no indication that AF447 and Atlantico discussed the weather between ORARO and TASIL. Nor does the transcript contain (other than one or two references) the radio communications between other flights and Atlantico, say between 0100 and 0300.
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Old 9th Jul 2009, 22:06
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Taking the concensus that CB clusters in the ITCZ may well have been at least a contributory factor in the loss of AF447 - since there are daily trans-Atlantic tracks promulgated in relation to jetsreams - would it be beneficial to develop a similar track forecasting system for trans-hemispheric flights to avoid significant active areas of the ITCZ? (each area of ascending air has an area of generally descending air not too far away - reasonably predictable at least on a scale of several hours).
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Old 9th Jul 2009, 22:51
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Possible cause of lost ACARS ?

In my prevoius post (page 162 / message 3234) is suspected that the rain and hail attenuation would be the cause of the lost 31 seconds of ACARS-txm:s. JD-EE replied on page 164 /message 3263 that it only could be possible IF the A/C already had diverted to a lower flightlevel.

To be sure that the figures was right in this matter, I started to do several "link-budgets" to the Inmarsat bird that is in geo-position (=fixed service). As transmissions on this latitude is nearly straight up, the rain-attenuation is approx 8 times worse than having the same situation above Paris/France for example.

While I made these calculations and checked the equipment on this flight, I made a cruel discovery, I therefore ask all aviation experts here to have a close look at my findings and please replay if this could be the "missing detail".

When calculating the attenuation I got a max of approx 18 dB:s that could make the L-band carrier lost temporary for the satellite, but this only if the flight had diverted to a lower flightlevel around approx 15.000 feet.
But the real suprising fact is that the Satocm unit of EMS 3800 has limit of 530knt/mach 0.95 with max pressure of 4,5kPa. I then suspected that there was a chance of the Satcom-dome getting "ripped-off" in high speed, and if that was the case, there should be a 50% chance that the dome would slam into the a/c - vs and leave a impact trace.

So I checked on the 2 first photos from the rodder pictures in the water and compare with the Paris may 31st photo, and indeed, there is a quit big impact trace on the rodder that would match the size of the dome from the cockpit.

Last edited by Art-Deco; 10th Jul 2009 at 06:26. Reason: Edited photos got lost in insert...
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Old 9th Jul 2009, 23:17
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AF447 Autopsies

Quite simply the reason why BEA hasn't got the autopsy reports yet is bureaucracy. Some small official is insisting that the exact procedures are followed. It happens everywhere and especially when two different jurisdictions are involved.
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Old 9th Jul 2009, 23:31
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Triskel, When they got to the problem area was about 4 hrs after their last land briefing so everything would be different then. If you mean transmit them up a picture of their route and the satellite info by all means do that if possible. It is possible if they pay for the capability. Most airlines now discourage use of satcom because of the expense. More than likely their onboard radar if used properly would have given them even a better picture of what they were dealing with. If the captain was on his rest break the two remaining pilots were running the program and radar.
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Old 9th Jul 2009, 23:34
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Out of the loop ?

A contribution by Pilotaydin, on the forum (Pitot freezing=>overestimated airspeeds=>nose up=>stall):
____________________________________________________________ ________
I would like to share a small story about something i experienced in the sim a while back, as a demo from my instructor towards the pros and cons of fbw and envelope protection...

we "flew" through an area of icing in the sim, the probe heat function and the airbus a/c itself is designed to fly through known icing, however, that doesn't mean it can withstand anything put in its path... our pitots iced over and our airspeeds started indicating 300+ at high altitude, which is bad news, because we're passing Mmo and Vmo, so the a/c as per design pitched up.... after about 20 seconds of this, as the speed wasn't decreasing, we were actually stalling and losing altitude, and the sidestick = useless, it wouldnt let any one of us pitch down, we started a large rate of altitude loss. Even if we disconnected the a/thr system and idled or added full power, the damn nose was pitched up....we went down 30,000 feet into the water outside jfk in the sim....during that descent, nothing came up on the ecam, just the warning chimes of overspeed.......we of course didnt just sit there, it was a demo we were observing he different things going one point my hand did go up towards the PRIM 1 and PRIM 2 computers...i thought maybe if i let them out of the loop, we could go to altn law but i decided not to intervene to see the outcome....
knowing your systems helps, and the a/c doesnt always provide an answer to us....

Things need interpretation and over automation sometimes leaves us out of the loop...the other day over the atlantic, at 35,000 feet, we got master caution chime that said :
Start valve open and it asked us to switch off the bleed to one engine....leaving us with only one bleed left over the atlantic....are you gonna follow the ecam? or are you going to emergency cancel it?

____________________________________________________________ _
btw, I don't get how a Pitot obstruction only (of the ram port/the drain) can lead to overestimated airspeeds (and possible overspeed alarms): if the dynamic pressure cannot be overestimated (?), then it has to be the static pressure which is underestimated (?) and this would imply that the static ports are also blocked and that altitude has been lost since their blockage ? Is that so ? Would there be other ways to overestimate airspeeds ? On the contrary, a blocked Pitot ram port is sufficient to roll back the airspeed to 70-80 kts.
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Old 9th Jul 2009, 23:37
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If the captain was on his rest break the two remaining pilots were running the program and radar. I still have found no information of the experience of these two pilots. Why?
What do you want to know about them you can't read in the preliminary report?
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