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AF 447 Search to resume

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AF 447 Search to resume

Old 23rd Apr 2011, 09:07
  #3841 (permalink)  
 
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Are we too critical of that first search?

It occurs to me that a search & RESCUE operation does not necessarily focus on the most likely location, but the most likely survivable location. Taking an extreme case, if someone were lost in a sea where survival in water that long was unlikely, then no matter how improbable it is, you would favour searching any islands first. In the case of AF 447, you would search in a manner that gave the best chance of quickly finding a large number of survivors, therefore ruling out any 'it fell like a stone at the LKP' and is now sitting at the bottom of the sea' scenarios.
Of course, once RESCUE is ruled out, most likely position then dictates the place and style/speed of search, but we must not be too critical of the initial response, it had a different purpose.

Last edited by paull; 23rd Apr 2011 at 11:56. Reason: typo: now, not 'not'
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Old 23rd Apr 2011, 09:08
  #3842 (permalink)  
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As with everything 'aviation' in my long time 'doing it', I now find myself again 'surprised' that with the technology existent in ACARS, with regular position reports, a system of 'Flight Watch' was not apparently present in AF - it may be that no operator does this? We can, I think, safely say that an earlier 'alert' to the crash would not have improved survivability, but in another scenario where a semi-successful forced landing/ditching took place it could well do. As suggested here, it is not difficult to pass or extract reports from the ACARS stream, and AF ops would not be particularly busy at that time of day. AF could well have known something was amiss far earlier, or at least have been alert to watch for the next pos report.

Regarding suggestions that 'serious' events had begun well before 0200, have we not established that the Captain was not in the flight deck at this time? I don't know about other Captains, but I would have been.
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Old 23rd Apr 2011, 10:17
  #3843 (permalink)  
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BOAC

Have to agree. Confidence in your F/O (s) is one thing, but going to sleep as the a/c approaches the ITCZ quite another.

I'm sure the F/Os were competent, but I think most Capt's would like to be on the F/D and most companies would expect them to be, during flight through this sort of adverse weather.

I wonder, if he had stayed up front, whether his greater experience might have saved the day. Maybe we'll find out soon but it's probably too intangible a parameter to be revealed by data.

Personally, I rarely even go for a pee. But then, I'm not a longhaul guy.
 
Old 23rd Apr 2011, 10:18
  #3844 (permalink)  
 
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Originally Posted by CogSim View Post
That is interesting. How was the track for AF447 obtained? Im assuming the tracks from other aircraft were also from the same source. ...
You can tell that the data used for the AF447 is the 'nearest 10 minute +/-0.3NM accuracy' from ACARS, time in seconds past 01/06/09 00:00:00

http://www.bea.aero/en/enquetes/flig...data/AF447.txt

AF459 track data is every 10 seconds, 100 times more precise, must be from a flight computer download.

http://www.bea.aero/en/enquetes/flig...data/AF459.txt
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Old 23rd Apr 2011, 10:26
  #3845 (permalink)  
 
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I am alive

I believe this sort of thing will become standard with the proposed Gate to gate technology where computers will control al phases of flight
Flight plans will be gone
primary radar will be gone.

EUROCONTROL - Gate to Gate
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Old 23rd Apr 2011, 10:31
  #3846 (permalink)  
 
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If we get data off the CVR, then I have a strong suspicion we are going to find long periods of silence leading up to the loss of control.

Falling asleep on the job is not the same "black and white" process we normally experience each night. When we fall asleep normally, there is a gradual but one way transition from awake to asleep, and once asleep you stay asleep. This is because your brain is not sending contradictory signals to stay awake.

When falling asleep while trying to stay awake, the process is usually a lot more chaotic. Brief microsleeps and long periods of being "half-asleep" (where you are technically awake but have very low levels of awareness and responsiveness) are interrupted by sudden periods of wakefulness as you catch yourself falling asleep. Critically, judgement is severely impaired during this process and the individual has very limited insight into their state of mind.

During this process however, it is quite possible for some intermittent purposeful activity to take place. A driver will navigate a corner in the road. A pilot might try and make a radio call. Sooner or later however, a microsleep will coincide with a bend in the road.....

I believe this process explains the failure to divert around weather, and also some of the communication inconsistencies. However the flight continued to proceed uneventfully as far as the Captain (? sleeping in the rest area), the CC and the pax were concerned. Suddenly something major happened (? initiated by pitot tubes freezing, ? weather related upset), and it all turned to s.....

Its not just pilots. ATC also.

Fourth ATC Sleeping Incident At Reno | AVIATION WEEK

On the surface, it is staggering that in 2011 commercial flights can land at the nations capitol with ATC asleep at the screen. Given the recent spate of sleeping ATC in US, I wonder if a similar problem is not the explanation for the apparent staggering failures of ATC that were responsible for the passage of AF447.

If this is the explanation, we need to look at the system issues rather than point the finger at the individuals concerned. Humans are not bad working through the night when the job involves either manual work, unpredictability, or continuous cognitive processing. Police officers on patrol or a cab driver in a busy metro area looking for a fare are not likely to go to sleep. It is more a problem with routine activities (such as long distance driving), or where the job require oversight and monitoring in case of an unexpected (and unlikely) problem.
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Old 23rd Apr 2011, 12:50
  #3847 (permalink)  
 
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slats11

If we get data off the CVR, then I have a strong suspicion we are going to find long periods of silence leading up to the loss of control.

Falling asleep on the job is not the same "black and white" process we normally experience each night. .......
The implication of what you write automatically equates a quiet CVR with falling asleep.

CVRs in cruise often have long periods of silence.

let's not start writing analysis of symptom-cause without all the facts
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Old 23rd Apr 2011, 12:54
  #3848 (permalink)  
 
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Could the Captain have left the flight deck to investigate an issue ? What would be normal practice ?
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Old 23rd Apr 2011, 13:33
  #3849 (permalink)  
 
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The implication of what you write automatically equates a quiet CVR with falling asleep.

CVRs in cruise often have long periods of silence.
Sure. But hopefully not in a scenario where the weather ahead was of some concern and other aircraft around were deciding to divert.

I believe the best explanation is one that incorporates all of the following:
1. Some inconsistencies in radio communications leading up to the crash, and no aircraft heard anything from AF447.
2. Apparent decision not to divert around weather (everyone else that night decided to divert)
3. Captain apparently not up front. Question for the pilots here. Would recognition of worse than normal weather ahead and the requirement to make an active decision about this (ie to either initiate a significant diversion or not to divert) generally warrant a call to the Captain if he was taking his rest break?
4. Subsequent sudden and catastrophic loss of control - for a number of possible reasons. But it was sudden and catastrophic. No radio calls. No signs of preparation for an emergency. CC not in their seats.the bridge

Much of the discussion on this thread starts at number 4. There are very likely to have been significant factors already in play well before 4.
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Old 23rd Apr 2011, 13:51
  #3850 (permalink)  
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Originally Posted by slats
3. Captain apparently not up front. Question for the pilots here. Would recognition of worse than normal weather ahead and the requirement to make an active decision about this (ie to either initiate a significant diversion or not to divert) generally warrant a call to the Captain if he was taking his rest break?
- as you can see the 'absence' from the flight deck does not fit my M. O., but when I aired this eons ago on one of these threads I was informed firmly by some of the long-haul 'experts' that 'Captain's rest' is rostered and taken as rostered in some companies which I find bizarre! We will not know the facts UNLESS the CVR is recovered and readable.
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Old 23rd Apr 2011, 14:00
  #3851 (permalink)  
 
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Are you sure about CC not being in their seats ? Of the 9(?) CC, how many have been recovered ? You would think that the flight experienced some progressive roughness before 'whatever happened' so wouldn't everyone be seated ?
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Old 23rd Apr 2011, 14:18
  #3852 (permalink)  
 
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Flightwatch

BOAC said
.../..., I now find myself again 'surprised' that with the technology existent in ACARS, with regular position reports, a system of 'Flight Watch' was not apparently present in AF - it may be that no operator does this? We can, I think, safely say that an earlier 'alert' to the crash would not have improved survivability, but in another scenario where a semi-successful forced landing/ditching took place it could well do. As suggested here, it is not difficult to pass or extract reports from the ACARS stream, and AF ops would not be particularly busy at that time of day. AF could well have known something was amiss far earlier, or at least have been alert to watch for the next pos report.
It should be admitted here that the "Flightwatch" that one are referring to, is in France the CCO or, in English, the OCC (Operations Coordination Centre). Other airlines use term "Operations" for the same duty. You call them at any time and they tell you the ins and outs of their flights. Flightwatch means, I would say, in French "Contrôle des vols" or "surveillance des vol". These expressions are not used simply because it would be too long to say and, may be also, a little bit pompous or "m'as-tu-vu" (show-off) in our language. There is also a Law in France that forbids the use of English terms in official and public domains called Law Jacques Toubon. (aka Loi Jacques Allgood...)
Busy or not busy is the question. We don't have the workload of the man/woman in charge of the 447. Was the 447 the only flight under his/her responsibility? Very unlikely but it may be clarified later on. As a matter of fact how the AFR CCO structure works is a mistery.
The AFR CCO started to worry about the lack of informations from the 447 after the AF559 crew contacted them by ACARS (0418z), indicating that the radio contact was lost with flight 447. They send an ACARS message at 0424 to the 447. It was shortly after DAKAR requested the AF559 to contact the 447. (04 11 53/ 04 20 27z, BEA report).

Why SAL did not launched, at least an INCERFA after 0506z is a great interrogation to me. No radio contact, no RADAR contact but nothing is done.
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Old 23rd Apr 2011, 14:26
  #3853 (permalink)  
 
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ACARS... I think we can read too much into this. 1 type, in 1 airline, with 1 ACARS service provider / type, happens to provide some interesting messages. In the absence of anything else, these have proved useful to Investigators.

That's a long step from "mandating" a standard across all airlines / types a data stream and protocol that is used for "flight monitoring". For starters, not all types/airlines will use Satcom for ACARS, and it is not cheap. I work for a large UK company, and one of our LH types only has ACARS via VHF (or did when I flew it). If the ACARS is in VHF comms, then so generally will the crew...

For those using the various ACARS systems, they frequently go to standby, or someone retunes / uses VHF3 etc. To call out the full SAR system for a mid ocean rescue everytime the ACARS / Satcom goes on the blink will keep them well occupied

Accidents / incidents such as this are relatively rare, and the cost of uploading effectively FDR type information via satellite will not be trivial across the whole world's fleets. Far rarer will be the occasion it makes 1 jot of difference to survivability.

Knowing "what" downed this A330 is of interest to PPRuNe readers, and also to AF, Airbus and the families. But is it (or will it turn out to be?) so necessary as to enforce FDR data uploads? The cost and delay of the search is significant, but I suspect small compared to implementing such systems.
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Old 23rd Apr 2011, 14:43
  #3854 (permalink)  
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I think you have run slightly amok, there, NoD - I guess it's the heat

I was basically referring to AF who HAVE the 'data stream' as you put it with position (was it every 10 mins?) and it would be very simple to use this in an Ops Flightwatch system.

As to its 'value' - since it is already in use, what is the cost if it enables one recovery of living souls?

Wash my mouth with soap and water if you thought I was suggesting BA should spend some money on it. Indeed, not even a suggestion that ALL LROPS airlines should HAVE to do it, just an idea.
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Old 23rd Apr 2011, 14:47
  #3855 (permalink)  
 
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Regarding the flight of LH507, which appears in the first interim report, and has since 'disappeared'.

The first interim report states that LH507 preceded AF447 by "about 20 minutes" at FL 350, and describes the experience of LH507:

The crew reported that it flew at the upper limit of the cloud layer and then in the clouds in the region of ORARO. In this zone they saw green echoes on the radar on their path, which they avoided by changing their route by about ten nautical miles to the west. While flying through this zone, which took about fifteen minutes, they felt moderate turbulence and did not observe any lightning. They lowered their speed to the speed recommended in turbulent zones. They saw bright St Elmo’s fire on the windshield on the left-hand side.
(TASIL is 119 NM from ORARO.)

As AF447 had estimated ORARO at 02h00, this would indicate LH507 passed ORARO at around 01h40.

The last communication from AF447 to ATLANTICO was at 01h35.43, when they thanked ATLANTICO for the SELCAL test. Assuming they went to SELCAL mode immediately following that acknowledgment, they would not have heard communications, if any, between LH507 and ATLANTICO on its deviation between ORARO and TASIL. Whether there was any communication between ATLANTICO and LH507 prior to 0135 regarding weather ahead (and which might have been overheard by AF447) will have to await a future BEA report.

Presumably future BEA reports will also have timestamps for communications between ATLANTICO and the flights following AF447 as they deviated on approaching the mesoscale convective complex north of ORARO, and give some indication when these flight crews began evasive action. And if the CVR is both recovered and readable, their actions can be compared to what happened in the cockpit as AF447 encountered this complex and proceeded to penetrate it.
_____________
Aside from valuable lessons learned for application to future searches, any fingerpointing on the timing and adequacy of the initial search for AF447 will only begin in earnest if the recorders are recovered, but are unreadable because they have been in the water too long.

_____________
Mr. Optimistic, if I recall correctly, three CC seats were recovered. None appeared to have been occupied at the time of impact. That probably meant at least one of the CC was not in his or her seat.
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Old 23rd Apr 2011, 15:00
  #3856 (permalink)  
 
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Are you sure about CC not being in their seats ? Of the 9(?) CC, how many have been recovered ? You would think that the flight experienced some progressive roughness before 'whatever happened' so wouldn't everyone be seated ?
You would indeed had there been progressive roughness. Hence the loss of control was sudden and catastrophic.

Amongst the debris recovered were a set of 2 CC seats. Pretty much intact. Empty. And harnesses retracted / unbuckled.

I did the math a while back. From memory, they recovered 4/9 CC, 1 Captain, and 45/216 pax. So they recovered a disproportionately high percentage of the CC. Sure, this could be due to chance. But there are two factors which should lead to finding more pax than CC
a) CC are secured in more substantial harnesses than pax (shoulder straps in addition to lap belt)
b) Without being disrespectful, CC are likely to be closer to their ideal weight than the average pax (younger and thinner). Hence the average pax would be more likely to float than the average CC.
So if everyone was the same pre-crash (ie belted in), you would expect to find an excess of pax. Instead we have the opposite. This makes me think that loss of control was sudden, some people were already strapped in anyway (mostly pax and hence not recovered), and the CC were mostly recovered as not strapped in.
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Old 23rd Apr 2011, 15:09
  #3857 (permalink)  
 
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ACARS - I-am-alive

NigelOnDraft
"That's a long step from "mandating" a standard across all airlines / types a data stream and protocol that is used for "flight monitoring". For starters, not all types/airlines will use Satcom for ACARS, and it is not cheap. I work for a large UK company, and one of our LH types only has ACARS via VHF (or did when I flew it). If the ACARS is in VHF comms, then so generally will the crew...

For those using the various ACARS systems, they frequently go to standby, or someone retunes / uses VHF3 etc. To call out the full SAR system for a mid ocean rescue everytime the ACARS / Satcom goes on the blink will keep them well occupied

Accidents / incidents such as this are relatively rare, and the cost of uploading effectively FDR type information via satellite will not be trivial across the whole world's fleets. Far rarer will be the occasion it makes 1 jot of difference to survivability."
_____________________________________________

Nigel, all good points, but you have missed my point.

Where available (e.g. narrow band satcom) a once a minute message could be used.
All long haul overwater aircraft are still required, are they not, to be HF equipped, hence, if ACARS equipped, an Alive message could be sent, say, every 10 mins.
The ground based computer auto triggering could be set quite wide in the case of HF to say something like, trigger an alarm after 4 messages missed (ie. alert after 40 minutes which is usually longer than mandatory ops normal radio calls).
What the ground does with the triggered alert is not unlike what happens with SAR phases, ie. uncertainty phase, distress phase, search phase etc. Obviously, there would be protocols around this.

Purpose is to cut wait times for positive determination of a lost aircraft from hours (elapsed time from last contact to ETA), down to an hour or half an hour or less, depending on comms methods implemented.

Again, these are all rules-based decisions that can be programmed into the ground based computers to make allowances for variations in comms used.

As to "standard message protocol", ACARS implementations incorporate many industry standards anyway. There probably exist message structures/protocols defined by ARINC standards. The value of defining a standard protocol to an I-am-alive message is, particularly where noisy open channels are used like HF, that a possibility exists someone else may hear a message that is missed by the "owner" airline's ACARS ops system. Hence, an opportunity is created for any airline's ACARS ground system to automatically reroute a heard message destined for another airline. The owner airline's system can automatically determine if received re-routed messages are copies of an already received message, or replacements of unheard messages.

I am not suggesting this is necessarily simplistic, or without cost, but it appears to be technically well within the capabilities of currently installed hardware requiring only additional software functionality.

It doesn't even have to be implemented by all airlines ... it can start with one and grow from there.

Given that the likely total incurred costs of AF-447's loss will run into hundreds of millions of dollars, the industry incurring a few tens of millions to implement R&D for a software change would appear to be well worthwhile if it could trigger a faster initiation of a search phase, increasing potential for rescue of lives or earlier retrieval of recorders.
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Old 23rd Apr 2011, 15:24
  #3858 (permalink)  
 
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Pilots wakefulness

Gentlemen,

there are at least two reliable, solid indications that the guys up front were active right in the middle of the ACARS message stream, that is between 0210 and 0214.

First is the pair of FLAG ON CPT FPV and FLAG ON F/O FPV.

FPV is not selected ON as normal cruise operation. Someone had to turn it ON, about one minute into the sequence. Read again the timings, they are public domain as part of the first BEA report.

Second, is this highly interesting item :

02:14:20 - .1/FLR/FR0906010213 22833406AFS 1,,,,,,,FMGEC1(1CA1),INTERMITTENT

The failure has AFS (Auto Flight System) as its identifiers. AFS is Airbusese for Autopilot. But wasn't that A/P OFF at the beginning of the sequence ? And it was turned OFF by the aircraft itself, following Pitot probes failure. And now we find it as the identifier in an FMGEC fault, which means AFS detected a fault in FMGEC1. Who turned the A/P back ON and reactivated it ?

This last message was acquired at about 02:13...

Isn't that somehow correlated with the Airworthiness Directive issued this winter regarding A/P reengagement after an UAS condition ?

Of course, everything would be much better for those surviving highly interested parties if the pilots were asleep from 01:35...

Who are the interested parties ?

Think More (I should perhaps make it a trademark)
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Old 23rd Apr 2011, 15:29
  #3859 (permalink)  
 
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All long haul overwater aircraft are still required, are they not, to be HF equipped, hence, if ACARS equipped, an Alive message could be sent, say, every 10 mins.
Ummm, have you ever used HF? It's hard to enough to talk over, passing data I would think impossible. Just listen to the bandwidth of SELCAL for data transfer - maybe 1 or 2 chs /sec AFAIK ACARS works over VHF (los) or Satcom (when VHF unavailable).

What the ground does with the triggered alert is not unlike what happens with SAR phases, ie. uncertainty phase, distress phase, search phase etc. Obviously, there would be protocols around this.
As above, I think a sense of realism is needed over MEL requirements, reliability, Sat coverage. It sounds from this forum these messages just roll in... maybe reality is more like "occasionally, when all the holes line up, the messages come through". In practice it is probably somewhere between the 2. I just know from my little Airbus that even the "simple" VHF system frequently goes on standby, sometimes for a minute, sometimes the rest of the flight... It is not designed to be "reliable" for safety related purposes, let alone initiate an SAR alert.

It is clearly "possible". But you are needing to upgrade the aircraft systems, the comms systems, the airline systems to robust / reliable, not just "nice to have features".

If you really want such systems, why aren't you looking at, say, CPDLC? Since this is used for ATC Comms, it has a safety basis, it is "new" technology, it is being mandated effectively over the next X years, it already interacts with ATC rather than the airlines? It is a universal standard, rather then airline specific. Surely better than a system which is really using a ZX81 type audio stream to a tape recorder to transfer data
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Old 23rd Apr 2011, 15:31
  #3860 (permalink)  
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Rolls of course does "Total Care", an ambitious real time engine monitoring program for those carriers who have selected it as part of leasing power from Rolls. I have seen a vid that showed a "control center" where many dozens of people were monitoring their engines on wing while various clients were flying.

It is not inexpensive, one is certain, however the application could certainly be modified to apply to other flight parameters, especially in long haul, or ETOPS??

slats

There was a long discussion re: Captain duBois and his actions, possibly to include the time of the accident. I recall that FC rest is directly behind the cockpit, and Starboard? Also, Captain launched and climbed to cruise in the first hour, then took his planned rest, RP sliding into the LS. At 0200, Captain's rest period was over, he should have either been in the cockpit, or a little late, on his way. We think he was unrestrained because of his later recovery in the water. There are many potential theories, but I believe he would have re-assumed command from his own chair, the RP then replacing F/O in RS and the original RS would rest. There is much potential for chilling theory, for it is astonishing to me at least that this happened at all, and one has to believe that it had to have taken a devilishly and star crossed sequence to upset and destroy this flight.
 

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