Chances of locator beacons transmittors working
 

1) Fixed ELTs(Qty 2) - Works only in case of over land crashes.
2) Portable ELT(Qty 1) - Someone has to turn it on and not under water
3) Beacons on rafts(Qty 8) - Need salt water contact to activate, but has to be above water level to transmit.
4) ULBs on CVR/FDR(Qty 2) - Underwater only, limited range, limited life.

Big assumption these are maintained properly.

So sonar sweeps and ROV visual searches have better probability than these.

Yes, an expanding square spiral search pattern is what you would expect for a blue water search around a vague search datum point, but the recorded track pattern as seen on AIS looks to me much more like a contact investigation track.

Looking at the marinetraffic web site, the PMS Burullus has simply vanished without trace. Its position was last reported, what, 48 hours ago.

In the past half hour or so a French Warship described as "9014" (no other details given) has now appeared on the same bit of Mediterranean. As yet there is only one position report so there is no track to see. It is shown as heading just north of west at 10 kts.

"9014" may be this:

https://en.wikipedia.org/wiki/French...re_%28L9014%29

During the search for AF447 they used a French nuclear submarine...
source
Submarine begins search for Air France jet's black boxes - World - CBC News

Are they doing it now secretly ?

There is also the "passive" transponder that stays in a very low power-consumption mode until it is interrogated whereupon it "wakes up" and starts to transmit. After all, there is no point in a locator beacon using up all its battery power in the few days immediately after a crash when there may not yet be anyone in the area looking for it.
What you need is a device that is fitted to the plane that uses very little power whilst listening for someone out to locate it, then when it detects a signal of someone or something hunting it down, it responds and uses its battery up when it knows that there is something close by looking, and picking up its transmission signals

That is what the ULB does.

HMcB was describing how a ULB should ideally work, not what they currently do.

If they are on station, typically they will turn off the AIS.

This will keep the news helos and other aircraft from interfering...

2 days ago.

http://i.imgur.com/NMGRoxF.jpg

Ideally a beacon should transmit every so often last known position & depth (5,10,30,60 minutes?), but be listening as well. When it detects a trigger signal, it will go into full transmit for 1,3,6 hrs? It would then revert to the previous mode to save battery until triggered again. It would be good if it transmitted the received trigger signal strength too. The trick is that the beacon receiver will be affected similarly as the surface receivers are. Signals can be blocked by terrain as well as thermoclines (temperature layers in the water that can reflect/refract signals), however the surface trigger transmitters can have a lot more power. Of course ideally you don't want to be transmitting whilst trying to listen, so the beacon would need to know to transmit at a set minute of the hour (:00?)

In this scenario you could drop 100's (1000's?) of buoys with the transmitter & receiver over the suspected area, thus covering a much larger area more quickly. Some of the buoys could be designed to sink to a specified depth & the return to the surface (or part of the buoy) to transmit a found beacon.

At the moment it seems a bit old fashioned the way searching is done. Even today 1000 receivers could be made, dropped on the area, slowly sink down to the seabed & then if one of them detects a pinger, release a transmitter back to the surface & transmit its location & depth of detection. Hopefully several will pick-up the signal & a map can be made to narrow the location further.

Can we do better with today's technology than we are at the moment?

That is very similar to the now discontinued radio silence periods of 15 to 18 and 45 to 48 mins past each hour where W/T Morse transmissions on 500 kHz would cease (it was a calling frequency as well as a distress frequency). Similarly, 00 to 03 and 30-33 mins past each hours for R/T Speech transmissions on 2182 kHz.

This method enabled the automatic keying of a low efficiency medium power W/T transmitter powered by batteries for a lot longer than would otherwise be the case.

The Wall Street Journal writes about the history of the avionics bay smoke detector:

Smoke Alerts Like That on Flight 804 Have Raised Questions in the Past
(Paywall, use this Google search to try to circumvent: Google Search for Article)

WSJ article May 27-28, 2016
 

Another link to the WSJ article titled, Smoke Alerts Like That on Flight 804 Have Raised Questions in the Past

http://on.wsj.com/1OSGvk0

NTSB links on this incident:

Current Synopsis, Preliminary:

http://www.ntsb.gov/_layouts/ntsb.av...no=2&pgsize=20

Dockets:

Accident ID DCA11IA040 Mode Aviation occurred on April 04, 2011 in New Orleans, LA United States Last Modified on January 18, 2012 14:01 Public Released on January 18, 2012 14:01 Total 49 document items

I'm wondering why the final report has not been released.

ELT transmitted two bursts (NAOO)
 

At 2.36am (Local) NOAA “received two bursts from the beacon, but was unable to make a location”. “They received the beacon ID and were able to correlate that with the beacon that was on MS 804”.




Satellites Captured Doomed EgyptAir Jet?s Distress Signals - Bloomberg


Business: Washington Post Business Page, Business News

Thank you thf, for bringing this up, and airman1900 for linking the NTSB reports. It's a very intersting reading about smoke detection system and related procedure.

Concerning MS 804, beside using optical detectors (see Airbus statement), I would add that the smoke warning(s) were triggered several hours after take off. At this point, such warnings would be very unlikely resulting from prior ground contamination of smoke detectors, which is what happen in most cases.

Also, ACARS of MS 804 are reporting two warnings at 0:26 and 0:27 (Lavatory and Avionics), which make it even less likely that they were related to nearly simultaneous faults of two detectors reporting spurious alarms. They are related to different compartiments and systems.

Moreover, both warnings were possibly triggered by cockpit adjacent areas (Lavatory A door is only a few centimenters away from the cockpit door while the avionics bay is right below the cockpit's floor) ; on top of it, the avionics vent system is using cockpit air to refresh both instrument panel and the whole bay, where the avionics smoke detector check the exhaust ducts for particles.

Finally, the two system faults reported at 0:26 and 0:28 are telling something related to the cockpit right windows heating sensors (sliding first, then fixed one) ; both window sensors faulted... but not the right windshield which is also heated by the same WHC-2. Hence, one could think that it wasn't related to the state of WHC-2 in the bay which was still working on the right windshield and triggered no fault on its own. In case of such a single fault reported, one would suspect the sensor first, the computer next and the wiring last. Now, if the computer is not at fault, we are still left with two faults with different wirings, sensors, and circuit breakers...

So far, and without any further evidence, I would rather suspect that those smoke warnings reported were actually real ones ; also, it seems to be more likely due to an external system cause, probably in cockpit, like a sudden surge of temp close to the right sliding windows ; the original event would have to last for at least 1-3 minutes (0:26 to 0:28) in order to trigger the second sensor fault on the fixed right window.

Considering that the investigation is in possession of the full ACARS content, they would have more details on each time stamping; they would also be able to tell if any probable delay happened during the string of ACARS between 0:26 and 0:29. But based on what we have, it's still possible to make some sense out of the first faults reported.

Of course, it's not the only scenario as one could also suspect a more complicated sequence, like a wiring combustion or electrical issue contaminating one and second right window heating system. It's only less likely because it would alert the crew of something wrong (like smell) in the cockpit, and probably well before this point.

Now, looking at any previous report of incident at cruise involving cockpit windows overheating in A320 might be more interesting than spurious smoke warning events, in order to understand if this could make more sense than an external surge of temp in cockpit.

Who needs ground contamination? Because I would not let them smoke in the flightdeck, my first officers used to smoke in the forward toilet. I won't say how they overcame the detector (mostly). Its like pushing water uphill sometimes.

I would suspect the sensor or the wiring well before assuming that there is a computer issue. Of course, sometimes it is wiring to the computer that is the problem.

It might be interesting to consider that the wires for temp probes are usually significantly smaller than any other wires in a wiring bundle and are thus the first to melt through if the bundle overheats for some reason. (Those tiny wires can also be the devil to crimp although I suspect in aircraft standards are a bit higher than for the marine stuff that I deal with.)

Slightly related case in point -- this week the state of charge gauge on our electric utility vehicle (think 'glorified golf cart') failed. It is cheap junk and since the car ran fine and the charger reported no issues I was going to disregard it and replace later. Actually thinking about this thread and the importance of checking out all electrical faults, I opened the battery compartment and found that one battery had been venting acid, eating through the copper connectors. The one that was eaten completely through first was the small one for the state of charge meter. The big ones that carry a lot of amps @ 48V were partially eaten through.

As a passenger you are probably not driven mad by all the mis-information dressed up as factual information and delivered by flight simmers who research stuff on the net then pretend they are professional pilots.
To a passenger it comes across as knowledgable and experienced, to actual airline pilots it is obviously rubbish.
Personally I have no problem at all with pax who post here if they preface their posts with that fact, or, if they don't give advice or operational opinions.

From a quick search, sounds like the warning source hasn't been identified and the items that failed had actually been switched off per checklist. Meanwhile other incidents have been prioritized for the investigators.

contamination
 

Silver, sorry but my comment about ground contamination wasn't related to your point.

I was refering to NTSB discussion involving spurious smoke detection which is all about the Avionics bay fire detection (see above NTSB report linked) and the following Airbus procedure ; it's not about the toilets that one can avoid being flagged while smoking.

Indeed, most of false AVNCS SMOKE triggered in flight were due to contamination on the ground released after the take-off phase. And it's an old discussion lasting since a while.

My other point was to underline that both Lavatories and Avionics were detected in MS 804 ACARS, almost simultaneously, and several hours after take-off. It's unlikely related with someone trying to smoke in lavatories that get the smoke detector warning in Avionics bay triggered.

TFU 26.15.15.001 in July 1999

*DESCRIPTION: SOME OPERATORS HAVE REPORTED MANY CASES OF SPURIOUS AVIONICS SMOKE WARNINGS, LEADING TO "AVIONICS SMOKE" OR "LAND ASAP" ECAM MESSAGES. THESE WARNINGS HAVE MAINLY BEEN REPORTED ON GROUND, HOWEVER THERE HAVE BEEN A FEW CASES GENERATED IN FLIGHT, SHORTLY AFTER TAKE-OFF AND GEAR RETRACTION.

*CONSEQUENCES: N/A

*INVESTIGATION STATUS: THE AIRCRAFT FLIGHT PHASE CONFIGURATION WHERE AVIONICS SMOKE WARNINGS HAVE BEEN GENERATED FALL INTO TWO MAIN CATEGORIES; ON GROUND AND TAKE-OFF.

- ON GROUND - WITH THE AIRCRAFT ON GROUND THE AVIONICS VENTILATION IS SET TO 'OPEN LOOP', WHEREBY OUTSIDE AIR IS USED TO PROVIDE VENTILATION FOR THE AVIONICS COMPARTMENT. IN ENVIRONMENTS WHERE HIGH HUMIDITY AND/OR CONTAMINATION EXISTS (JET EFFLUX/BLOWN DUST ETC). IT IS POSSIBLE FOR THE SENSITIVITY OF THE AVIONICS SMOKE DETECTOR TO BE AFFECTED CREATING AN ALARM CONDITION.

- TAKE-OFF - THE AVIONICS SMOKE WARNINGS ARE INHIBITED FROM 80KTS TO 1500 FEET. DURING THIS TIME IF THE AVIONICS DETECTOR GOES INTO ALARM THEN A 'LAND ASAP' (IN AMBER) IS GENERATED ON ECAM. THE ONLY WAY TO IDENTIFY THE CAUSE OF THE AMBER WARNING IS BY DEPRESSING THE RECALL BUTTON ON THE ECAM CONTROL PANEL. INVESTIGATIONS HAVE DETERMINED THAT SOME OF THESE 'LAND ASAP' WARNINGS HAVE BEEN GENERATED DUE TO A PREVIOUSLY LATCHED, BUT INHIBITED AVIONICS SMOKE WARNING THAT HAD BEEN GENERATED WHILST THE AIRCRAFT WAS ON GROUND. INVESTIGATIONS HAVE SHOWN THAT THE IONIZATION TYPE SMOKE DETECTORS SENSITIVITY IS SUBJECT TO THE AMBIENT TEMPERATURE, PRESSURE AND AIR CONTAMINATION WITH MOISTURE, DUST OR POLLUTION. THE HIGHEST SENSITIVITY TRANSLATED INTO A VOLTAGE SHIFT BEING ON THE GROUND AND DURING TAKE-OFF.

*INTERIM SOLUTION: N/A

*MAINTENANCE ADVICE: IN CASE OF AN 'AVIONICS SMOKE' WARNING TRIGGERED AND LATCHED ON GROUND, FWC1 AND FWC 2 SHOULD BE RESETED ONE AT A TIME BY MEANS OF THEIR C/B (3WW C/B 49VU FOR FWC1 AND 2WW C/B 121VU FOR FWC2). THIS WILL CLEAR THE LATCHED CONDITION OF THE WARNING IF THE AVIONICS SMOKE CONDITIONS HAVE DISAPPEARED. THEN AN UNDUE 'LAND ASAP' ALARM WILL BE AVOIDED. OPS ADVICE: N/A REPERCUSSION ON A/C DISPATCH: N/A PERMANENT OR FINAL SOLUTION: A NEW GENERATION OF SMOKE DETECTOR PN CGDU2000-00 USING AN OPTICAL TECHNOLOGY HAS BEEN DEVELOPED IN ORDER TO REPLACE THE 'OLD' GENERATION OF IONIZATION TYPE SMOKE DETECTOR. THIS NEW GENERATION TYPE OF SMOKE DETECTOR HAS A DIFFERENT TRIGGERING PRINCIPLE AND IS THEREFORE NOT AFFECTED BY THE TEMPERATURE AND PRESSURE CONDITIONS. IN SERVICE EVALUATION (6 MONTH PERIOD) OF AVIONICS OPTICAL SMOKE DETECTOR PN CGDU2000-00 HAS BEEN PROPOSED TO TWO OPERATORS. DEDICATED SB A320-26-1052 HAS BEEN RELEASED MID JULY 2000. THE IN SERVICE EVALUATION HAS BEEN COMPLETED SUCCESSFULLY. SB A320-26-1052 REVISION HAS BEEN RELEASED THE 30TH OF AUGUST TO INCORPORATE ALL AIRLINES IN THE EFFECTIVITY.

Not sure what you mean, but we dont search the way that was show on AIS. They are spending too much time stopping/slowing down for the turns, and the optimum search is in a straight line, especially at the depths they are working at.
This is a basic towed array search pattern that we use to optimize area:
http://i.imgur.com/DmOW9Am.jpg

The fish is towed, so anything over about 4 kts will cause it to cavitate, (or the harmonics in the umbilical) and degrade the measurements.

DOS hired to search/recover

Deep Ocean Search - Contact & Info

Underfire

Your explanation of a possible search pattern is interesting. However, when the PMS Burullus was visible on AIS there were several puzzling things whcih do not seem to fit the scenario you have described. She was sailing at variously 0.4 kts and 0.3 kts all the time. She did not seem to be slowing to turn, it was just very, very slow all the time - and there were many observation points along its route where data was available, so this was not a sampling problem. AIS reports show many items of data, including the ships actual heading as well as its course over the ground. The heading showed that at all times when zig zagging the vessel had its head pointing NE, no matter which way it moved. When moving to its search area the heading was different, suggesting this was not just "stuck" data in the AIS stream, but was the actual heading as it moved. I guess that was holding the ship "head into the prevailing wind", but I have not checked the weather. Lastly the scale of the pattern it was sweeping was very "tight", with only 1Km - roughly 0.5 nautical mile - along each "long" leg and with 200 odd metre gaps between passes.

None of these seem to me to fit with a towed anything. Maybe it was a "dangled" something, or perhaps as has been suggested it was tracking a self powered ROV with or without an umbilical.

Any thoughts about what it was using?


Just noticed French Warship 9014 is back in the area and is "moving" in a way that suggests it is looking for something. Moving at 10 or 11 knots most of the time. There is a period where there were no position reports when it moved only a few Km in 4 hours.


And there is a survey ship - the Hugin Explorer just to the NE of the supposed site. It arrived in the area from Cyprus at 11 knots and now seems to be just drifting.

Update Egypt authorities
 

http://www.civilaviation.gov.eg/News...s_28_5_16.html

"CAIRO - 28 May 2016

Investigation Progress Report (4) by the Egyptian Aircraft Accident Investigation Committee

The investigation committee received satellite reports of the electronic emergency signal that came out of the Emergency Locator Transmitter (ELT); which is equipment that sends automatic signals to satellite in the event of a crash or fall into water. Concerned search units were then informed of the updates recorded by the satellite to intensify searching in that area.

Efforts to search for the data recorders of the A320 continues; including the use of the most advanced search equipment of Alseamar company that was brought aboard the French vessel. The Ministry of Civil aviation has also made agreement with DOS (DEEP OCEAN SEARCH) company for other equipment with high capacity to receive signals and conduct sonar scan, in order to diversify research methods and to carry them out in the shortest time possible.

On the other hand, the investigation committee has started studying the information received from the Greek air traffic control about the accident; more information of the records of the radar that had followed the path of the plane before the accident, is expected to be also received."

Looking up French warship 9104 I see her described by Wiki:
Tonnerre (L9014; lit. Thunder) is an amphibious assault helicopter carrier of the Marine Nationale.

Undoubtedly a very capable ship, but not the first type that springs to mind when selecting a vessel of opportunity for what amounts to hydrographic survey work.

I wonder if perhaps they are using her as a base for naval ASW helicopters to cover a large area with numerous dips of their dunking hydrophones to listen for the pinger(s). Half a dozen of those helicopters could join up a lot of dots and do vastly more acoustic searching in a limited time than a full spec hydrographic survey vessel could ever hope to achieve.

As AT1 points out, the limited track info that we have/had from AIS is not at all consistent with towing a hydrophone eel array, nor with towing a towfish. Hence my speculative conjecture, in which I should have used the word 'surmise' instead of 'conclude', that they were doing some kind of contact investigation rather than the boustrophedontical pattern of an area search.

In Le Monde this afternoon:
EgyptAir : les boîtes noires ne seront pas repêchées avant 12 jours

Good stuff Caz
 

I am not sure about the ASW frequency capabilities, and the various naval assets around the world may not wish to "advertise" all their capabilities.

At least we know the passive sonar can easily detect very low freq sounds like propellors that are turning. Apparently, they can detect higher freq sounds like whale calls, which seem to be at upper range of human hearing.

Listening for "pings" that are up in the near ultrasonic range sould not be that hard for the ASW sonobouys or maybe subs. You don't need more than one ASW plane like the Orion or the new USN one to drop a dozen sonobouys in a very good pattern. The problem is revealing military capabilities. Up to me I would claim we found the beacon a hundred miles away! OTOH, if you drop a good pattern within a few clicks and don't detect the ping before the French boat does, then.........

Another warship, the "F262 Erfurt" which is described as a UN warship and also as "DE", is now heading for the area at speed from Cyprus. It may be just coincidence.

The track of the French warship is very very odd - with no obvious "pattern". Maybe it is searching the surface to recover floating debris spotted by helicopters or the Orion rather than an undersea search?

The Hugin Explorer has stopped drifting and is now closing at speed on the area where the French warship is.

I would have thought the military world would be OK revealing quite a lot about their ability to detect a distress "pinger" - particulary if they have had time to go to port and pick up suitable hardware. This is not going to reveal much/anything about their ability to detect ships or subs.

Not likely that dipping sonar will be the search option of choice for this signal (the cable only goes down so far) but that ship is a great C2 platform and can take on board a variety launchable vehicles that can aid the search. Also good for further search for stuff afloat with the Search capability of its helicopters. (Per AT1's post).

Translation from Le Monde: It will not be possible to recover the black boxes of the flight Paris-Cairo EgyptAir before at least 12 days, the time that a specialized vessel arrives on site, reported Agence France Presse (AFP) sources close of the investigation.
The Airbus A320 suddenly disappeared from radar screens at night May 19th before breaking sea between Crete and the northern coast of Egypt for reasons still unknown. Only the analysis of flight recorders, the "black boxes", will allow to know exactly the causes of the accident.
Egypt and France have signed agreements with two French companies specialized in finding shipwrecks in deep water, and Alseamar Deep Ocean Search (DOS). Forty Egyptians, including the crew, and 15 French are among the victims of the crash.
Read: What is known about the plane EgyptAir disappeared between Paris and Cairo
complementary role
"Both companies have a complementary role, the first to locate the" pings "black boxes [echo sonar emitted by their tags] the second to go down and recover" with a robot, explained AFP in Cairo a source close to the investigation who requested anonymity. But "the DOS specialized ship left the Irish Sea Saturday and will reach the presumed area of ​​the crash in about 12 days, after embarking in Alexandria Egyptian and French investigators," she added.
The information has been confirmed by other sources close to the investigation, which evoke a depth of about 3000 meters in the research area, some 290 km north of the Egyptian coast.
Three DETECTOR-6000 Alseamar immersed equipment can detect "pings" up to 4000 to 5000 meters, were loaded aboard a French naval vessel, the Laplace, who left Corsica Thursday . It should arrive in the presumed area of ​​the crash "Sunday or Monday at the latest," according to one source.
Automatic alerts issued
"Pending the DOS ship equipped to detect" ping "deep water but most of robots able to descend to 6000 meters to retrieve the black boxes, there will be no waste of time and since the Laplace attempt to locate the meantime, "says one of these sources, which evokes, even in 12 days," a very good chance to recover the flight recorders through the combination of the two French companies. "
Time is running out as beacons of these flight recorders can emit only "four to five weeks" before exhausting their batteries.
Read also: In Cairo, MS804 flight passengers families EgyptAir angry against the authorities
The hypothesis of the attack, initially put forward by Egypt, has lost ground to that technical incident since it was found that automatic alerts have been issued by the unit two minutes his fall, indicating smoke in the cockpit and a failure of the computer managing orders.

Don't assume naval submarines are already set up to search for 37.5khz pingers.
The French sub, The E'meraude, wasn't set up for listening for 37.5khz, nor did they know they were supposed to be, in the initial search for AF447. Looking for Black Boxes wasn't a mission they'd had. Only, maybe, after the batteries for the pingers had died, and it was too late, was The E'meraude possibly set up for 37.5khz. The area the airplane was eventually found in, had been crossed off as already searched by The E'meraude, but they were not equipted to detect 37.5khz. It's deep in the BEA report.
A hard lesson learned, so, I hope, maybe, that mistake won't be repeated.
Knock on wood. It's beginning to sound like the searchers have it under control. May not be long yet.

C2 is good. C2 is very good.

But to find sunken ships and aeroplanes you need ships that can find sunken ships and aeroplanes.

Don't forget there's also the 'fishing immigrants out of the sea' operations going on in this approximate area. The Tonnerre could well be engaged in that.

Coagie has pointed out that most of the naval ASW gear is not optimized for the high freq beacon we are looking for.

One current sonobouy system only goes up to 2400 Hz or so with any good sensitivity. I would imagine the subs to have much larger bandwidth, but just try to get the specs for those!!!!

As Lonewolf said, "dipping" by ASW choppers ain't gonna work. The gear is not real good when passive and needs to "ping". It is not designed for deep work, as most operational subs won't be down there at a thousand meters or more, ya think?

I would place my bets on a sub, but they can't down to the depths we are looking at, but might get a "ping" if the acoustics are right.

Okay, so why would you select an amphibious assault ship with helicopters to find a wreck in three thousand metres of water?

Just askin 'cos I doan unnerstand.

I sort of understood why the RN offered the services of a passing "coalition" RFA, but that was a matter of hours after the aircraft went down.

What, on earth, is an amphibious assault ship with helicopters doing in a hydrographic job?

Okay, I'll give you that, but what, on earth, is an amphibious assault ship with helicopters doing in a hydrographic job?

9104 is not "Tonnerre"
 

@Cazalet33
Helicopter Carrier Tonnerre was not dispatched for supporting this operation. So this tag "9104" is more likely given to PHM Jacoubet which is, since May 23, only doing surface sweep and visual researches for debris and they deployed two aircraft, a Falcon 50 and Atlantic 2, in addition to Egyptian and US assets deployed.

See official French Navy media, 28 May situation :
Vol Egyptair : Point de situation au 28 mai | colsbleus.fr : le magazine de la Marine Nationale

Hydro Vessel Laplace would be on spot by tomorrow with pinger locators. Search for beacon will start then. Next, in about a dozen days, they would be joined by Deep Ocean Search R/V John Lethbridge (sailing from Ireland sea) for the deep sea recovery mission.
Deep Ocean Search - Home

AT!,

Yes, that is correct. The explanation in the post was regarding searching with a towed array. The pattern shown in one of my last posts was not a general search pattern. It is also not indicative of ROV deployment. An ROV is not towed around, it is self powered. The ship must remain relatively stationary, or basically on station, not moving at all, moving perhaps in 5m increments, the DP keeping it as stationary as possible.
The concept is to hold, and let the ROV drive around. One cannot have too much slack in the umbilical, as the current drag on the line would be too difficult for the ROV to overcome, and you dont drag the ROV around.
They may have deployed the towed device that looks for the pinger. It is tough with only one vessel as one cannot triangluate.
Cheers

From Le Monde 29/05
"Trois DETECTOR-6000 d’Alseamar, engins immergés capables de détecter les « pings » jusqu’à 4 000 à 5 000 mètres, ont été embarqués à bord d’un bâtiment de la Marine française, le Laplace, qui a quitté la Corse jeudi. Il doit arriver dans la zone présumée du crash « dimanche, ou lundi au plus tard », selon une des sources."

English Translation: 3 Alseamar DETECTOR-6000's, devices capapble of detecting the "pings" to a depth of 4000 to 5000 metres, were taken on board a French Marine vessel, the Laplace , which left Corsica on Thursday. It should arrive in the presumed crash area by "Sunday, or Monday at the latest", according to one of the sources.
EgyptAir : les boîtes noires ne seront pas repêchées avant 12 jours

We agree completely, that was part of the point in my post. This is a task for specialized ships and equipment.
Supporting the effort.

BPC Tonnerre is in Pacific Ocean
 

I just wonder why there is still people talking about BPC Tonnerre and researches for MS804 while she is actually part of the Naval Group Jeanne d'Arc sailing in the Pacific Ocean with FLF Guépratte.

There was US Marines from Okinawa visiting Tonnerre... a few days ago.
Coopération franco-américaine pour le groupe Jeanne d?Arc