Go Back  PPRuNe Forums > Flight Deck Forums > Tech Log
Reload this Page >

AF 447 Search to resume

Tech Log The very best in practical technical discussion on the web

AF 447 Search to resume

Old 1st Nov 2010, 01:06
  #2321 (permalink)  
 
Join Date: Jun 2009
Location: NNW of Antipodes
Age: 81
Posts: 1,330
Received 0 Likes on 0 Posts
JD-EE
"Why in heck didn't they hear the last few calls from ATLANTICO?"
The assumption is the crew selected SELCAL watch the moment they confirmed the SELCAL check with ATLANTICO.

The real question should be, "Why didn't ATLANTICO SELCAL them when receiving no reply? The controller would have had the code keyed in, and needn't look it up and key it in again.

I suspect the controller got busy with something else and thought he'd SELCAL them prior to TASIL with their transfer instructions. Did he try doing that? I don't know, and maybe as they were already on a virtual flight plan, he just let them go, and in doing so passed the problem to DAKAR.

mm43
mm43 is offline  
Old 1st Nov 2010, 01:45
  #2322 (permalink)  
bearfoil
Guest
 
Posts: n/a
Well, if conjecture is up on the controllers, I would go with radio difficulty, rather than "letting them go". A break in procedure is unacceptable, or certainly should be. Report TASIL hadn't come up, 447 was, what? Upset? trying to navigate out of the cell? No attempt to follow procedure is too lax to entertain, No? The radio inop/switching system may have played a role in lack of comm? Occam would say that the a/c was certainly in trouble on or about the comm failure, so the onus is on the ground procedures, which is handy, we have that data, or should. BEA does, right?

bear
 
Old 1st Nov 2010, 02:19
  #2323 (permalink)  
 
Join Date: Jun 2009
Location: NNW of Antipodes
Age: 81
Posts: 1,330
Received 0 Likes on 0 Posts
Bearfoil

From BEA Interim Report No.1 -
At 1 h 46, the DAKAR controller asked the ATLANTICO controller for further information regarding flight AF447 since he had no flight plan. The ATLANTICO controller provided the following elements: A332, from SBGL to LFPG, SELCAL: CPHQ.

The DAKAR OCEANIC Regional Control Centre created the flight plan and activated it. The result of this was to generate a virtual flight following the planned trajectory in the DAKAR FIR between TASIL and POMAT. There was no radio contact between AF447 and DAKAR, nor any ADS-C connection. The flight remained virtual.

At 2 h 47 min 00 s, the DAKAR controller coordinated flight AF447 by telephone (ATS/DS) with the SAL controller (Cape Verde) with the following information: passing the POMAT point (leaving the DAKAR FIR) estimated at 3 h 45, FL350, Mach 0.82.

At 2 h 48 min 07 s, the DAKAR controller told the SAL controller that flight AF447 had not yet established contact with him.

At 3 h 54 min 30 s, the SAL controller called the DAKAR controller by telephone (ATS/DS) to confirm the estimated time for passing the POMAT point. The latter confirmed that POMAT was estimated at 3 h 45. The DAKAR controller stated that the crew of flight AF447 had not contacted him to correct its estimate. The SAL controller replied that the estimate was probably later. He asked the DAKAR controller if there was any change. The DAKAR controller then said that he was going to try to contact flight AF447.
There is no indication that the ATLANTICO controller attempted to contact AF447 again, and once the virtual flight plan had been created AF447 was left to its own devices.

mm43
mm43 is offline  
Old 1st Nov 2010, 03:06
  #2324 (permalink)  
bearfoil
Guest
 
Posts: n/a
mm43

I get from the log why ATLANTICO would not establish (or try) contact with 447 after DAKAR was given 447's profile. I would ask then did ATLANTICO apprise DAKAR '447 "negative contact" (TASIL)'??

thanks, bear
 
Old 1st Nov 2010, 04:00
  #2325 (permalink)  
 
Join Date: Jul 2009
Location: Not far from a big Lake
Age: 81
Posts: 1,454
Likes: 0
Received 0 Likes on 0 Posts
Additional Data

Project Deepspill final report is located:http://www.boemre.gov/tarprojects/37...l%20Report.pdf
The sea bottom in that area was 844 meters, so not so deep as AF447 is likely to be. The SLAR image presented was of a crude oil test with a volume of 60 cubic meters. The film thickness was reported to be on the order of 1mm. A test was also conducted with marine deisel of a similar volume, however a SLAR image was not provided of that test. The length between tic marks on the screen was 10 km, so the spill was approximately 9 km long. Marine deisel is fairly similar to jet fuel in its physical properties.

The satellite image of the pollution spot was taken on June 2nd 2009 at 8h16m. There is a grid overlaid on this image (apparently by the provider and I would be interested if anyone has hard information on the grid spacing. I had initially assumed a significantly larger spacing than did griz however with a swell spacing of 330 meters crest to crest, it appears that griz has the dimensions pretty well nailed. For those wishing to re-read the drift group report for additional info on the pollution spot, see page 134 of the following report : http://www.bea.aero/en/enquetes/flig...oup.report.pdf

Last edited by Machinbird; 1st Nov 2010 at 14:11.
Machinbird is offline  
Old 1st Nov 2010, 04:23
  #2326 (permalink)  
 
Join Date: Jun 2009
Location: I am where I am and that's all where I am.
Posts: 660
Likes: 0
Received 0 Likes on 0 Posts
mm43: "Why didn't ATLANTICO SELCAL them when receiving no reply?"

Color me astonished when asking, "They DIDN'T?" That, to me, makes them sloppier than the DAKAR operation's reputation.

{O.O} REeeeeeaaaalllyy!
JD-EE is offline  
Old 1st Nov 2010, 06:53
  #2327 (permalink)  
 
Join Date: Jun 2009
Location: NNW of Antipodes
Age: 81
Posts: 1,330
Received 0 Likes on 0 Posts
Bearfoil

There has been no evidence presented by the BEA that indicates any attempt by ATLANTICO to contact AF447 post the three non answered calls at 0136. That means there was no attempt to establish its position prior to transfer at TASIL, and no mention has been made that ATLANTICO even advised DAKAR that they even tried.

To put it bluntly, once DAKAR advised ATLANTICO that they had not received a flight plan for AF447, and ATLANTICO had passed the essential plan details on to DAKAR at 0146, ATLANTICO "let the aircraft go".

Radio procedure and etiquette had been performed normally up to 0136, but as pointed out in the last paragraph, it then "went to hell in a handcart".

mm43
mm43 is offline  
Old 1st Nov 2010, 09:46
  #2328 (permalink)  
 
Join Date: May 2010
Location: PLanet Earth
Posts: 1,329
Received 104 Likes on 51 Posts
Project Deepspill final report is located:http://www.boemre.gov/tarprojects/37...l%20Report.pdf
The sea bottom in that area was 844 meters, so not so deep as AF447 is likely to be. The SLAR image presented was of a crude oil test with a volume of 60 cubic meters.
As previous contributors have already stated the length of the narrow 'leg' of the spill in the AF447 case does not fit to fuel rising from the bottom.
It is much too short and narrow for that.

But we should consider that an Airliner which crashes usually doesn't come to a full stop immediately.
the dirction of the narrow 'leg' of the spill roughly matches the flight path which AF447 would have to be taking in order to arrive where the spot was found.
So a possible scenario trying to explain the shape of the spill could be a first (severe) impact releasing a big amount of fuel where the bigger oval part of the spill was seen followed by continued travel of the wreckage for a couple of hundred meters to the SE. Than sinking of the wreckage continuously releasing decreasing amounts of fuel. Sinking and resurfacing of the remaining fuel could take a couple of hours, roughly matching the 1300m length of that 'leg'.
Just a desperate attempt to match the finding (spill) to the assumed cause (AF447 impact).
Generally I'm not really that convinced anymore ithat the spill was really linked to the crash. On the other hand: Where there any ships around at that time (+/- 1 or 2 days) that could have caused the spill?
Did anyone check in Vesseltracker or similar?
henra is offline  
Old 1st Nov 2010, 12:01
  #2329 (permalink)  
 
Join Date: Oct 2009
Location: berlin
Posts: 152
Likes: 0
Received 0 Likes on 0 Posts
grit spacing

@machinbird, the grid spacing in direktion latitude is 1 minute of angle = 1 nautical mile = 1852 meter
the grit spacing in direktion longitude at this latitude is nearly the same (cos 2.6 *1852=1850 meter)
grity
grity is offline  
Old 1st Nov 2010, 12:45
  #2330 (permalink)  
 
Join Date: Jun 2009
Location: Bedford, UK
Age: 70
Posts: 1,319
Received 24 Likes on 13 Posts
grizzled

post 1862 - if that's what you were looking for
Mr Optimistic is offline  
Old 1st Nov 2010, 13:25
  #2331 (permalink)  
 
Join Date: Dec 2007
Location: Itinerant
Posts: 828
Received 77 Likes on 13 Posts
Mr. O,

Yes, thanks for that.
Because machinbird is quoting directly from BEA we can be assured the time being referred to is UTC.

machinbird: Thanks again.

grizz
grizzled is offline  
Old 1st Nov 2010, 14:10
  #2332 (permalink)  
bearfoil
Guest
 
Posts: n/a
henra

I quite agree with your posting. I think it is very premature to connect the image with 447's demise. I very much like your thought that a potential impact may have provided a "double" source of fuel. To expand on it: If there was somewhat more horizontal rotation at impact, a wing and the Tail (HS) could have stopped immediately as their edges "dug in" to the sea surface. The "sequential" nature of the edge-on contact would have provided the delay and created the discrepant trajectories such that we see two "spokes" emanating from the Hub where the two arms connect. Lighter, larger components (not containing fuel) would have broken and contributed to a debris field that was markedly independent of signature at the impact (origin).

mmm43

Thank you for the info. As we get back to the "causes" of the impact, a lack of communication between ATLANTICO and 447 is disturbing, no matter the cause. Giving the benefit of the doubt to the land station, a lack of response from the a/c may well be common, and worthy of no mention at inter station hand off. DAKAR's nonchalance may be indicative of this. For two critical nav and land supports to accept the situation begs the question...Why are they there? If indeed over ocean flight is developed well enough to allow 100 per cent independence, budget issues need to be addressed. I mean this not in snide fashion, seriously, why are adjuncts to InterContinental flight budgeted if they provide no support? At any time during the flight, a passenger or crewmember could push a button on a personal device and speak to any part of the civilised world, and perhaps a part not so civilised. SELCAL was ignored (noted by JD-EE), so the salient query becomes.....what are we doing? Comms would most likely not have saved the fate of 447, but the implications of expensively maintained (?) stations dropping the ball is cause for concern. At the least, a connection may have established a position, and focused the search, returning more of the plane to those affected, as well as vastly improving the chances of recorder(s) recovery.

447 generated no communications? We don't know they didn't attempt to. At 1:36, something went unaddressed. It is possible (likely) the problems this flight encountered began around this time, yet it was hours after that anyone took notice of 447's status? Call me old fashioned, but the concept of a "Virtual Flight Plan" leaves me cold. Tracking by "Proxy" seems a little too technologically....precious.

bear

Last edited by bearfoil; 1st Nov 2010 at 14:23.
 
Old 1st Nov 2010, 14:19
  #2333 (permalink)  
 
Join Date: Jun 2009
Location: Bedford, UK
Age: 70
Posts: 1,319
Received 24 Likes on 13 Posts
yet it was hours after that anyone took notice of 447's status

Although that is the impression the news media gave on the day, suppose we can't know what was going on behind the scenes. After all, even if it wasn't where it was meant to be it had to be somewhere and that string of ACARS messages in the middle of the night must have got someone's attention surely.
Mr Optimistic is offline  
Old 1st Nov 2010, 14:30
  #2334 (permalink)  
bearfoil
Guest
 
Posts: n/a
Mr.Optimistic

Certainly, that is correct. However, since there is no data supplied by BEA to warrant a different pov, the fact remains that public knowledge is what we are addressing. I credit an attentive employee of Air France with the release of ACARS to the public domain. Almost certainly, no Company approval would have been forthcoming. At the very least, maintenance issues are proprietary. No public dissemination is required, except as subpoenaed or demanded by a court, and for judicially established relevance. ACARS is intended to be "eyes only" and that for essential people exclusively. A corporation is legally treated as an individual, and privacy is universally acknowledged as a right. Where is this public spirited person now? Sweeping out a boulangerie at minimum wage?

cheers,
bear
 
Old 1st Nov 2010, 15:15
  #2335 (permalink)  
 
Join Date: Jul 2009
Location: France - mostly
Age: 84
Posts: 1,682
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by Mr Optimistic
that string of ACARS messages in the middle of the night must have got someone's attention surely.
It didn't. As explained by AF, no one in the Maintenance Dept paid any attention to it until shortly before the flight's ETA.

regards,
HN39
HazelNuts39 is offline  
Old 1st Nov 2010, 15:24
  #2336 (permalink)  
 
Join Date: Jun 2009
Location: NNW of Antipodes
Age: 81
Posts: 1,330
Received 0 Likes on 0 Posts
Bearfoil

Looking carefully at this comms sequence, and the blasť approach to ATC procedures which started way back in Rio de Janeiro when the Flight Plan wasn't transmitted to Dakar, you'd be forgiven for thinking that the outcome of the flight was doomed from the start.

Forget all that and just assume that AF447 was trucking along in its own little world, and they suddenly decided they wanted to share some bad experience with aircraft in their vicinity. Well, in their case they had 3 Air France aircraft all well within VHF radio range at 0212z -



- and it would appear they didn't avail themselves of the opportunity on 121.5 or 123.45MHz. The "why" or "why not" lies on the seabed somewhere out there, and what the recorders eventually reveal may be somewhat different to all the hypothesis expounded here.

NOTE:: The radius of each of the circles above is a nominal 250NM to the horizon at FL350, and in theory comms would be possible when the circumference of any circle had intersected another.

P.S. A little bit of background to the introduction of ADS-C procedures in the ATLANTICO and DAKAR OCEANIC FIRs can be found here.

mm43
mm43 is offline  
Old 1st Nov 2010, 15:27
  #2337 (permalink)  
bearfoil
Guest
 
Posts: n/a
HazelNuts39

Exactly so, but what could they Say? "We had the ACARS, it was quite an eyeful at the time, but we didn't act"? The release of the document(s) may have been retributive, by a defensive Mx wonk? AF was saying quite a lot after the fact. 447's ACARS profile was part and parcel the Genesis of the system in the first place, to garner resources and planning for mitigative Mx upon arrival. Waiting until ETA completely defeats the format, No? It rather defines the typical approach of "Blame others First". Or in the case of Lightning or Fortes Turbulences, "Blame Things First." Two things come immediately to mind re:121.5. The a/c was disabled relative to antennae, (there was no power), the crew were disabled. Or both. The lack of a message is the most important and glaring problem, at this point. Especially when directed. This is only to say there is no public revelation of comms silence, or activity. As described, the investigation is ongoing, so silence is expected relative to key facts, BEA is not the Press, after all. We should defer to the investigative judgment, for now. Were the CDR/FDR removed from 459 and data dumped?
If not, what a miraculous blunder.

mm43

Thank you for the graphic, it puts a face on what is probably being discussed behind doors. At 02:12, the accident is likely coming to impact. If the a/c (447) turned in either direction, 459 is the likely flight to interrogate for any desperate contact from 447. Why? In turning, it was allowing 459 to get "closer" to their problem, advantageous for reception of a 121.5 ELT at impact. I don't recall the 330's ELT profile, whether it was Pilot activated, or passive. If it activated, the following flight would have received the beacon, for Pilot recognition, or CDR reception and storage. I think this is unaddressed by BEA? Pursuant to my "Privacy" post above, the data could be still sequestered, since the Investigation is ongoing, and the data could be classified as "preferential". Similarly, other crew may be quiet regarding events 447 related. Pilots do that, from time to time. As with the deficiencies relative to ATC, why would this flight not have passive ELT? ELT is intended to alert independently, or so I have always thought. How can an incapacitated crew arm the ELT, one or both? Impact activated, the ELT takes the place of volitional action from a crew, Yes?

thanks indeed,

rgds
bear

Last edited by bearfoil; 1st Nov 2010 at 16:06.
 
Old 1st Nov 2010, 15:43
  #2338 (permalink)  
 
Join Date: Jun 2009
Location: Bedford, UK
Age: 70
Posts: 1,319
Received 24 Likes on 13 Posts
HN/B thanks

I keep forgetting that the world differs from the picture in my head ! Suppose all this is a backhanded compliment to the routine safety of modern travel.
Mr Optimistic is offline  
Old 1st Nov 2010, 15:51
  #2339 (permalink)  
bearfoil
Guest
 
Posts: n/a
Mr.O

Dangerous indeed it is, to ever consider safety 'routine'. It is elusive, ever and always, if one's attitude is complacent, No? Routine is for Marketing, a separate Corporate discipline.

rgds' bear
 
Old 1st Nov 2010, 21:52
  #2340 (permalink)  
 
Join Date: Sep 2009
Location: Around the World
Age: 74
Posts: 87
Likes: 0
Received 0 Likes on 0 Posts
mm43

You are discussing about the lack off emergency call.
Was there any problem with TX?
Departure at GIG was covered by MEL.

BEA interim report:

1.6.4 Condition of the aircraft before departure
On arrival of the Paris-Rio de Janeiro flight the day before the accident, the Captain reported a problem at the level of the VHF1 selection key on RMP1. The aircraft has three RMPs: RMP1 on the left-hand side, RMP2 on the right-hand side and RMP3 on the overhead panel. The ground engineer had switched round RMP1 and RMP3 to allow the aircraft to leave, in compliance with the regulations (departure covered by a MEL). The departure covered by this MEL item did not have any operational consequences.


bearfoil

Were the CDR/FDR removed from 459 and data dumped?
If not, what a miraculous blunder.
IMO, the data recorders arn't "twelve hours long play models"
So, i supose that only the last 40 minutes were available when AF459 landed.

Regards
NeoFit is offline  

Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.