AF 447 Search to resume

[mm43]

Where to next?

posted by rgbrock1;
There has been a lot of conjecture on this thread, granted. But I have also read plenty of hypothesis by professionals here which not only seem reasonable but highly accurate and probably very close to the mark. And in all these pages and pages of postings I believe what really happened to AF447 is contained herein.

Firstly, thanks for writing the above. The sentiments expressed are becoming truer as each day passes.

I for one am disappointed that the Phase 3 search has been a failure, but on the otherhand I am glad that there is less potential area to search. Whether that is done, will be a matter that will no doubt become political in France, and further searching has added costs to be met by someone. In defence of the BEA, they have hired the "best" expertise that they could find to help determine where AF447 crashed, and it is no fault of theirs [BEA] that the outcome has proved less than desirable.

Earlier in this thread, I made the point that all the data analysis and computer power available might lead to nought, now't, zip, zero in this very fickle part of the Atlantic Ocean. So be it.

However, way back in the giant AF447 thread I posted a possible scenario, which I had backed up with some careful research using currently available data and some 'between the ears' logic, and experience, in determining a possible impact position. The resulting graphic has now been superimposed on a portion of the BEA's latest Search Area image. The #2 position represents a nominal Vertical Stabilizer backtracked position using real-time OSCAR/NOAA surface currents and QuikSCAT 10m wind data obtained by satellite observation. The #1 and #3 positions are the result of applying corrections to both the mean surface current velocity and direction after "eye-balling" the overall trends. The 3°03.1'N 31°04.5'W position is the geometric centre of the resulting triangle, and that position is at variance with my original posting by 0.3'N due to a graphical error, since corrected mathematically.



Hopefully, the BEA will have a look in this area, and should it prove fruitless, then there is that much less area to search. On the otherhand, if they get lucky, everyone will be relieved and a contribution to my superannuation fund wouldn't go amiss!

PS Some of you may have noticed that the above position was left as "bait" on the recent search area graphics I had posted.

mm43

[barabenka]

Do you think there is a possibility that they searched wrong area?

[ChristiaanJ]

Minute addition from somebody who's now lived in France for over 35 years:
"Monter un scenario" is indeed "build, construct, establish" a scenario.

[mm43]

originally posted by barabenka;
Do you think there is a possibility that they searched wrong area?

Possibly, then possibly not.

A lot a rechecking of the data obtained will need to be done to ensure that hill/valley shadow areas have been covered from more than one angle. If any are found that haven't been, they would need to be checked again, otherwise a rethink is on the cards.

mm43

[CONF iture]

Originally Posted by rgbrock1

So for the BEA, or whomever was quoted by the above statement, to come up with such a cop-out is disingenuous at best. They have much more data and evidence to work with than anyone here in this thread. Yet they claim that can't construct a scenarios based on this evidence?

Those were merely the words from a journalist AF 447 : les recherches restent infructueuses

For sure we can not establish with certainty what happened, but we know that unreliable airspeed indication can lead to loss of control. We know also that a vicious unreliable airspeed indication could also inappropriately trigger some Airbus protections …

Yes, there are definitely some possible scenarios, and they are really not that far fetched.

But since the first of June of last year, I can feel that constant desire from the BEA to minimize the possible role of the Pitot tubes in that tragedy, am I the only one ?

[broadreach]

An apology to all and specially to MM43

For the last week I have been sending MM43 satellite positions of the "Anne Candies" and "Seabed Worker" as recorded by the Seasearcher AIS service.

MM43 has been laboriously inserting those positions in the graphics he's posted of the accident site and the search pattern. Pprune is fortunate in having people like him, with experience spanning a wide range of disciplines, contributing their time and knowledge.

But, unfortunately, I've been sending him duff data. The Seasearcher positions are off by a degree in both Latitude and Longitude. It's not just the Anne Candies and Seabed Worker; other commercial vessels are a shown as one degree south and one west of their known positions. There's no difference between the data picked up by vhf AIS receivers and that from satellites, so it seems likely to be a glitch in the programming at the Seasearcher end, and I'll be consulting with that team on Monday. In the meantime, continuing to send MM43 the data as received.

So, apologies to all and may that be a lesson to me in over-reliance on a technology that I could easily have checked beforehand! And, someday, it would be an honour to raise a toast to MM43 personally.

[Bobman84]

Originally Posted by rgbrock1

Then I'll ask a different question somehow related. Until AF447 what was the deepest of any wreckage of an aircraft which was successfully located and subsequently recovered? And, where?

SAA 295 in 1987 (Indian Ocean, near Mauritius); wreckage was successfully recovered from a depth of 4,900 metres (16,100 ft)—the deepest successful salvage operation ever conducted and I believe Aerolinee Itavia Flight 870 (Tyrrhenian Sea near Ustica, Italy)was a deep sea salvage as well.

A Varig 707 crashed in the Pacific Ocean, Japan in 1979 and was never found which would probably be one of very few aircraft never located at all.

[mm43]

"Seabed Worker" & "Anne Candies" 23 April positions

The graphic has been adjusted to account for the Lloyds Seasearcher data error, and the "Anne Candies" is shown completing a tow to the south through the area being scanned by the Remus AUVs. Shortly after the position plotted she makes a turn to starboard to commence a run to the north.

The "Seabed Worker" is not moving much at the southern end of the olive area.



mm43

[Titania]

For information.

French press claims to have seen a pre-report where (insufficient) maintenance of pitot probes may have been a factor in the accident. (link in French)

[approximate brief translation]
These may have been worn and less efficient, which may be explained by the time elapsed since the last maintenance. The regulations are that maintenance should be performed every 21 months and these regulations could be put into question.

[sensor_validation]

But, unfortunately, I've been sending him duff data. The Seasearcher positions are off by a degree in both Latitude and Longitude.

Only Longitude surely?

[vanHorck]

2 further interesting points from the same article above in titania's post.

1. the conclusion of poor maintenance of the pitot tubes is based on analysis of similar pitot tubes which have been confiscated by the justice department and which seem to have been poorly maintained. Later on in the article reference is being made to the cleaning of the pitot tubes which is alleged to have been in accordance with an agreed schedule (which by deduction could therefore have been insufficient).

A further observation at the start of the article where the Secretary of State for Transport (of France) has asked for continued search for the wreckage. That sounds like good news....

[mm43]

originally posted by sensor_validation ....
Only Longitude surely?

You are correct.

mm3

[mm43]

originally posted by vanHorck ...
A further observation at the start of the article where the Secretary of State for Transport (of France) has asked for continued search for the wreckage. That sounds like good news....

I imagine that Airbus will get pressured into coughing up for the costs of further searching. Paying a continuing 'Day Rate' is the cheap option, as the big standing costs of Mobilization and Demobilization are already accounted for.

mm43

[HazelNuts39]

Funding of extended search efforts

There have been various reports yesterday and today. The Transport minister requested BEA to keep looking 'with the support of' Air France and Airbus. A BEA official has confirmed having received the minister's request but added that the request was not accompanied by an offer of additional funding. Lefigaro.fr reports that Air France has said that it would be prepared to support an extension of the search:

Originally Posted by lefigaro.fr;23/04/2010

Air France, qui avait participé au financement de la campagne de recherches aux côtés d'Airbus, a déjà annoncé être prête à aller plus loin. "Si une nouvelle campagne de recherches est lancée, Air France ne manquera pas d'y apporter son soutien", a indiqué à l'AFP une porte-parole de la compagnie. Airbus ne souhaite en revanche pas faire de commentaires dans l'immédiat, a dit une porte-parole de l'avionneur.

HN39

[broadreach]

Sensor and MM43,

I checked the positions of a few vessels I knew to be alongside in Santos and, in fact, both Lat and Long were out by a degree. I hope to have an explanation by Monday.

[jcjeant]

Hi,

In french:
Les dossiers noirs du transport aérien

Google give this :

That the loss or inconsistency speeds measured results of multiple failures of several aircraft systems that seriously affect the operation of the aircraft. This is a serious incident that must be brought to the attention of the BEA

· That the loss or inconsistency of measured speeds can cause the aircraft outside its flight envelope and can be the cause of crashes

· What December 1995, Airbus has noted a lack of certification on pitot probes

· What about September 2007, EASA has noted the lack of certification of Pitot probes

· What about September 2007, EASA has noted the absence in the cockpit of a specific alarm "blocking Pitot"

· What about January 1999, the German BFU has recommended the amendment of the certification standards of Pitot probes

· That the procedure "IAS doubtful" applied by the crew of Air France recommends displaying thrust "Climb" which may cause the output of the flight

· That adherence to a false stall warning, as this may be the case when a blockage of pitot probes, (applying TOGA thrust) may cause the output of the flight

That in the "FLIGHT CREW TRAINING MANUAL, Air France recognizes that the blockage of pitot probes may result in multiple A330 extreme situations and that the crew had never been trained

· That the DGCA has never issued any instructions or info operational security-blocking pitot probes

· That TEMSI map presented to the crew of flight AF 447 shows a clear path to the point TASIL while the area is the busiest

· That A 741 447 AF offered a passage through the Intertropical Convergence Zone (ITCZ) over the A 873 reached

· That Air France does not provide maps observation satellites to crews

· That for many years, knew that the fluctuations or loss of information related to speed pitot probe could lead to the A330 outside its flight envelope at the crossing of affected areas of weather conditions such as those encountered in the ITCZ.

Air France · What therefore should have given instructions to his CCO increased surveillance flights during the passage of the ITCZ

That no information that could lead to a change of flight plan by the crew, was sent to AF 447 per CCO

That Air France · must prove that the 9 filings serious incidents precursors were addressed to the DGCA and the 9 corresponding RAS were sent to BEA!

That Air France · must prove that careful analysis of these nine serious incidents have been carried

That Air France · must prove that the lessons learned from the 9 serious incidents have been forwarded to the Authority

That Air France · must provide a list of corrective measures were taken following the analysis of these nine serious incidents

· That the DGCA has to prove that the RAS serious incidents related precursors pitot probes from Air France, Air Caraibes Atlantique and elsewhere have been included in time in the database ECCAIRS.

· That the DGCA should list the measures taken following the receipt of ASR serious incidents pitot probes from Air France, Air Caraibes Atlantic and elsewhere.

· The BEA has not issued any report or any recommendations about safety incidents related to serious pitot probes that occurred prior to the accident of flight AF 447.

That no safety study on incidents Pitot probes have been conducted by the BEA before the accident flight AF 447!

· That EASA should produce the studies about the events leading to the accident of flight AF 447 and the recommendations or actions.

· Airbus must give reasons for a further reduction of the interval between two cleaning pitot probes has not been recommended

· That inconsistency of measured speeds resulting from blockage of pitot probe is an "unsafe condition" that can cause victims usually with the destruction of the plane!

· That the "unsafe condition" may lead pilots to excessive workload which does not allow them to perform their tasks accurately or to complete them.

° As the date of the accident, the loss of primary information transmission is considered a risk "hazardous" in the documentation for the certification (CS25).

· That class yet EASA cases of inconsistency in measured speeds lower risk "major" in the safety analysis that describes the failure conditions associated.

· That the ice crystals occur in 40% of icing and heating the pitot probes requires so much energy to evaporate the ice crystals.

· That the publication of an airworthiness directive also called "airworthiness directive" is only intended to correct an "unsafe condition".

· A precautionary measure resulting in the issuance of a SAFETY INFORMATION BULLETIN (SIB)

· How to remove the pitot probe Thales AA, EASA issued an AD and not a SIB and that therefore there was indeed an "unsafe condition" that required a response.

· That EASA has claimed he was simply a precautionary measure to allay public

· That is curious to note that if EASA, Airbus, the DGAC and the BEA does not officially qualify the case of inconsistency speeds measured by the pitot probes "unsafe conditions"

· That the FAA, however, does not hesitate to do so.

· What about November 2009, EASA has edited the document "certification specifications, for wide Aeroplanes (CS-25) and that now, loss of all information transmission (primary and backup) is a risk of" Catastrophic "

Let · asked pilots to accommodate the failure of the pitot probes and ensure the accountability of an "unsafe condition" by applying a checklist so that it defined as an "unsafe condition "may lead the crew in distress or physical overload which does not allow it to perform its tasks with precision or their completion.

· That equipment must operate an aircraft throughout its flight envelope

Pitot probes · That does not work properly in some of the flight: in the presence of ice crystals.

· That it appears that neither BEA nor the DGAC or EASA, neither Airbus nor Air France have taken account of the "unsafe condition" that is blocking the pitot probes.

[Old Carthusian]

Deep Sea Searches

I thought I might add a comment here to those of us who are getting impatient. Aircraft crashing in deep oceans are rarely found and this seems to have been despite the most extensive searches. Pan Am Flight 816 out of Tahiti comes to mind and the loss of Rivet Amber come to mind. It takes a lot of luck to find an aircraft on the bottom of the ocean.

[mm43]

"Seabed Worker" & "Anne Candies" - 24 April positions

The "Seabed Worker" has spent the day to the south of the main search area, and the "Anne Candies" has moved around doing what appears to have been one tow north to south through the area previously scanned by the Remus AUVs. At the end of the day, both vessels were close together near 3°12'N and 30°48'W.



As has previously been mentioned the erroneous longitudes supplied by Lloyds MUI Seasearcher have been corrected, and the positions now plotted should be fairly accurate.

Thanks again to broadreach for the data.

mm43

[grizzled]

One hesitates to even express hope as to why the two vessels may be operatiing in this manner. In any event, may the best of luck be with them...

[MATELO]

Could this be the fate of 447??

Plane drops 18,500 ft over Goa, but lands safely

Could be an explanation and 447 may not have been as lucky as the Emirates jet.