Air Asia QZ8501 SUB To SIN Crash - Part 9

LovesCoffee · Sat Jan 10, 2015 4:32 am

Quoting rwessel (Reply 48):
It happened on one of AF447's recorders.

That's why my post starts with 'Possible, but highly unlikely'.

LovesCoffee · Sat Jan 10, 2015 4:34 am

Quoting fooflyboy (Reply 49):
I don't know what this would mean, or even if I am right. But they just don't look like physical scratches to me.

Pihero addressed this in the last thread.

rwessel · Sat Jan 10, 2015 5:37 am

Quoting LovesCoffee (Reply 50):

Quoting rwessel (Reply 48):
It happened on one of AF447's recorders.

That's why my post starts with 'Possible, but highly unlikely'.

Given the rather small number of airliner crashes, even one occurrence of a beacon separating from its data recorder makes the "highly unlikely" a bit questionable.

md80fanatic · Sat Jan 10, 2015 5:46 am

Sadly the efficiency of a pinger is dependent on a physical connection to the water, as any radio frequency-based solution gets attenuated by the water itself. If you packed the pinger securely inside the G-shock rated container it's pings could not be heard outside the enclosure.

rwessel · Sat Jan 10, 2015 5:56 am

Quoting md80fanatic (Reply 53):
Sadly the efficiency of a pinger is dependent on a physical connection to the water, as any radio frequency-based solution gets attenuated by the water itself. If you packed the pinger securely inside the G-shock rated container it's pings could not be heard outside the enclosure.

The pinger itself is supposed to be highly survivable.

md80fanatic · Sat Jan 10, 2015 6:12 am

Within reason though. The minimum qualification for an audio frequency pinger is contact with the water. A speaker, buzzer, etc. anything that will physically vibrate at a known frequency, that can move water molecules back and forth is acceptable. The problem is to expose such a mechanism to water makes it inherently vulnerable to crashes in water. The pinger's number one advantage is also, at the same time, it's number one weakness.

Perhaps when battery technology gets more dependable and has a higher capacity ... we could allow a long wire to extend from a reel, during an emergency descent, so that long period radio waves (which take a lot of power to transmit) could be sent instead of audio pings, but that time isn't now.

Long wire = antenna for Very Low Frequency RF (VLF - what submarines use to communicate while submerged)

[Edited 2015-01-09 22:17:54]

675kts · Sat Jan 10, 2015 7:27 am

BBC now reporting that the tail section has been raised so we'll have to wait and see what this yields. It will be difficult to tell exactly how much has been rasied until some decent photos are published

. I hope the FDR/CVR are still in situ and all the talk about pings coming from a slightly different area is just confusion or some other anomaly We really need to nail this accident as soon as possible for the benefit of the wider Aviation community. I guess Airbus will be anxious for answers too.

675kts · Sat Jan 10, 2015 8:00 am

Comparing a before and after, its possible to see that the rudder is still attached and appears to be locked in a fairly neutral position. It appears the tailcone/APU installation is totally missing

[Edited 2015-01-10 00:05:27]

Tobias2702 · Sat Jan 10, 2015 10:07 am

Quoting 675kts (Reply 56):
BBC now reporting that the tail section has been raised

Judging from the pics, it's only the vertical stabilizer...

Quoting 675kts (Reply 56):
I hope the FDR/CVR are still in situ

so that this question cannot be answered at the moment.

EY460 · Sat Jan 10, 2015 10:35 am

The tail has been raised.

http://www.youtube.com/watch?v=Qxdzp4HAFgg

They were not very gentle in the recovery operation. Is there the danger of losing some evidence? For instance how can they investigate those scratches which were seen in the underwater pictures?

[Edited 2015-01-10 02:45:00]

[Edited 2015-01-10 02:50:24]

RickNRoll · Sat Jan 10, 2015 11:07 am

Those who were hoping that the tail had detached from the rest of the body of the plane will be disappointed.

LovesCoffee · Sat Jan 10, 2015 12:02 pm

Quoting rwessel (Reply 52):
Given the rather small number of airliner crashes

Over 800 since 1960, although not all were hull losses. 1/800=.00125 or .125%.

BaconButty · Sat Jan 10, 2015 12:09 pm

Quoting LovesCoffee (Reply 61):
Over 800 since 1960, although not all were hull losses. 1/800=.00125 or .125%.

FWIW It's happened in quite a few cases fwiw but there was a reason:

Quote:

As has already been reported, the pinger was detached from the recorder.

The latest flight data recorder standards require that the underwater locator beacon or pinger, be bolted to the crash enclosure of the recorder.

Recorders involved in Alaska Airlines 261, Egypt Air 990, TWA-800, ValuJet- Miami, and several other accidents were built to an earlier standard that did not have the pinger bolted to the crash enclosure. This permitted the pinger to become detached from the recorder due to crash forces.

https://app.ntsb.gov/news/speeches/hall/jhc000203.htm

LovesCoffee · Sat Jan 10, 2015 12:36 pm

Quoting RickNRoll (Reply 60):
Those who were hoping that the tail had detached from the rest of the body of the plane will be disappointed.

I don't think anyone actually hoped the tail detached. Putting it that way lends kind of a carnival air to the discussion. People did postulate that the tail detached though. With what I saw on the YouTube video, it was the vertical stabilizer and some attached fuselage. And they were really rough in the process. Video is here.

MD11Engineer · Sat Jan 10, 2015 1:56 pm

Quoting md80fanatic (Reply 55):
Perhaps when battery technology gets more dependable and has a higher capacity ... we could allow a long wire to extend from a reel, during an emergency descent, so that long period radio waves (which take a lot of power to transmit) could be sent instead of audio pings, but that time isn't now.

Long wire = antenna for Very Low Frequency RF (VLF - what submarines use to communicate while submerged)

Have got an idea how long such a VLF TRANSMISSION antenna needs to be and how much power is required to get a reasonable signal out? The antennas on submarines are RECEIVING antennas, where the length isn't that critical. They receive a signal from shore that there is a message waiting for them and move up to periscope depth, so that they can stick their satellite or HF antenna out of the water.
The transmiiting antennas either need to be several kilometers (miles) long to be in resonance or they'll need elaborate networks for coils and top load capacitors to reduce physical size, which also reduces their efficiency to maybe 10% of the input power. I'm talking about transmitter powers of several kW to several MW.

Jan

[Edited 2015-01-10 05:57:49]

[Edited 2015-01-10 05:58:10]

Moose135 · Sat Jan 10, 2015 2:15 pm

Quoting md11engineer (Reply 64):
The transmiiting antennas either need to be several kilometers (miles) long to be in resonance

On the E-4B command post aircraft, they have a trailing wire antenna they can deploy to send messages to send VLF messages to USN submarines and the like. It is in the neighborhood of 30K feet long - some 5 miles in length.

md80fanatic · Sat Jan 10, 2015 2:19 pm

Even on receive only, the longer the wire (the closer to resonance) the more the gain, which equates to how much deeper the submarine can be and still be able to pull the signal from the muck and background static.

Perhaps a better implementation would be a VLF receiver (long wire) which would "listen" for a wake-up sequence transmitted from SAR boats searching above. Once received the audio frequency pinger could be started, with full battery power as opposed to having it pinging away with no one in range to hear it ... until the search teams arrive of course.

md80fanatic · Sat Jan 10, 2015 3:08 pm

Looking at that recovery video is it a regular occurance to have the teams handle the evidence so harshly, dragging it onto the boat with little concern for its shape or orientation?

Two days after this piece was found, there is still no reportage on other pieces which would need to be pretty close nearby in a breakup on ocean contact scenario. Even considering different floatation rate for different pieces, wreckage like this won't float for long.

EVAAIRBR076 · Sat Jan 10, 2015 3:58 pm

Here are some images of the tail

On one note i get the cheering from the rescue workers, but on the ohter hand it looks a bit rude to the family of the victims .

[Edited 2015-01-10 08:01:04]

rj777 · Sat Jan 10, 2015 4:04 pm

To me..... the way the aft fuselage looked when it surfaced suggest some sort of mid-air breakup. Or it might have broken off when it hit the water. Either way, I think it is now clear that this event was NOT survivable.

Kaiarahi · Sat Jan 10, 2015 4:18 pm

Quoting rj777 (Reply 69):
To me..... the way the aft fuselage looked when it surfaced suggest some sort of mid-air breakup.

Why? What aerodynamic / mechanical forces, in which direction(s) do you think were at work?

neutrino · Sat Jan 10, 2015 4:37 pm

Quoting md80fanatic (Reply 67):
Looking at that recovery video is it a regular occurance to have the teams handle the evidence so harshly, dragging it onto the boat with little concern for its shape or orientation?

From what can be seen of the pics and videos, the KRI Banda Aceh is using a winch to literally pull & drag the tail over the stern of the vessel. It seem to possess only a puny crane which look to be inadequate for the task of properly lifting the tail from the water. Don't Indonesia have a more appropriate asset that is up to the task? If not, why not call upon the recently arrived PLAN Yongxingdao submarine rescue/marine salvage rescue ship which have a massive crane that will be do the job more correctly?

namezero111111 · Sat Jan 10, 2015 4:48 pm

IIRC there was an article stating that they couldn't use a crane due to rough weather / seas.

LovesCoffee · Sat Jan 10, 2015 4:54 pm

Quoting neutrino (Reply 71):
From what can be seen of the pics and videos, the KRI Banda Aceh is using a winch to literally pull & drag the tail over the stern of the vessel.

Makes you wonder how many pieces of debris detached form the tail and fell back to the sea floor.

md80fanatic · Sat Jan 10, 2015 5:00 pm

Quoting namezero111111 (Reply 72):

IIRC there was an article stating that they couldn't use a crane due to rough weather / seas.

Leaving it down there until better conditions would probably have been sufficient. The recoders obviously weren't there. My concern is in the case of an inflight breakup, the tail may have seperated leaving nothing on the recorders from that point forward .. and these pieces of aircraft being then the -only- evidence that remains, and it's being treated with little concern for it's physical integrity.

lancelot07 · Sat Jan 10, 2015 5:08 pm

Quoting md80fanatic (Reply 74):

yes, but then these parts have gone through far worse than a not so careful recovery process.
Looks like the lower part of the tail including the horizontal stabilizers has broken away. The lower part of the rudder also seems to have broken away, while most of the rudder is still attached to the fin.

edit: where the 2 workers stand "inside" the tail in the 2nd photo, isn't that where the FDR and CVR are supposed to be ?

[Edited 2015-01-10 09:10:30]

Kaiarahi · Sat Jan 10, 2015 5:13 pm

Quoting md80fanatic (Reply 74):
Leaving it down there until better conditions would probably have been sufficient.

And then people on here would have been howling (even more) about the slowness of recovering it ....

namezero111111 · Sat Jan 10, 2015 5:19 pm

Quoting md80fanatic (Reply 74):

I agree. I just remember reading that if they couldn't use a crane due to weather they'd float it with balloons. Since that's what they did, the winch must have been part of that plan, too.

I would surmise though that investigators took plenty of pictures before "recovery damage" was imposed.
A metallurgist should be able to tell the difference between the recovery damage and accident damage.

That isn't to say that excessive damage should be imposed during recovery, of course!

Quoting Kaiarahi (Reply 76):
And then people on here would have been howling (even more) about the slowness of recovering it ...

That shouldn't be a factor in the investigation.

lancelot07 · Sat Jan 10, 2015 5:25 pm

Quoting namezero111111 (Reply 77):
That shouldn't be a factor in the investigation.

right.
But YOU tell that to TV, the press, the minister, and all on a.net who all want results yesterday !

7BOEING7 · Sat Jan 10, 2015 5:55 pm

Quoting namezero111111 (Reply 77):
I agree. I just remember reading that if they couldn't use a crane due to weather they'd float it with balloons. Since that's what they did, the winch must have been part of that plan, too.

I believe the initial plan was to use flotation (balloons) to get it near the surface and then crane the rest of the way.

md80fanatic · Sat Jan 10, 2015 5:57 pm

The left side of the above cropping from a previous image shows what looks like the aft emergency exit door frame. The emergency slide cover, and the exit sign is visible. I would assume that door frames are probably the most hearty part of the pressure vessel so it should take relatively more force to deform it. That door frame has been doubled over completely and I cannot see a situation where a flat, bottom down impact could cause such a deformation. It really looks like this piece would need to impact the water nearly upside down to account for such a shape. Part location reference can be established from the image below by comparing livery colors around the door frame.

namezero111111 · Sat Jan 10, 2015 6:02 pm

Quoting lancelot07 (Reply 78):

I doubt they'd listen, to *me*, but I hear you

I do want result yesterday, too. But they should be correct and based on solid evidence, of course!

[Edited 2015-01-10 10:29:25]

namezero111111 · Sat Jan 10, 2015 6:30 pm

DW reports the black boxes were not in the tail:

http://www.dw.de/no-black-boxes-found-inside-airasia-tail/a-18183519

This is discouraging. Any news on the pinger signals that were allegedly heard?

kanban · Sat Jan 10, 2015 6:38 pm

this video at the end shows a flash of more of the cabin structure
http://www.theguardian.com/world/vid...ght-plane-8501-tail-java-sea-video

SimonDanger · Sat Jan 10, 2015 6:41 pm

Quoting Kaiarahi (Reply 76):
And then people on here would have been howling (even more) about the slowness of recovering it ....

And the families of the victims, whom we are repeatedly told read this site, and whom deserve our care, concern and respect as we discuss this unfortunate accident, will they be accused of similar "howling" as well?

anfromme · Sat Jan 10, 2015 6:53 pm

Quoting SimonDanger (Reply 84):
And the families of the victims, whom we are repeatedly told read this site, and whom deserve our care, concern and respect as we discuss this unfortunate accident, will they be accused of similar "howling" as well?

Your point being? Are you trying to use the families of the victims as an excuse for the howling that's going on here about how slow progress has been?
Also, while I fully understand that if one lost a family member in an accident like this, you'd actually want answers even quicker than humanly possible, that's not something that'll dictate how the SAR crew operate. There's no point in risking even more lives by trying to recover debris when it's not safe for the rescue/recovery workers to do so.

CO953 · Sat Jan 10, 2015 7:01 pm

Quoting Kaiarahi (Reply 76):
And then people on here would have been howling (even more) about the slowness of recovering it ....

Quoting lancelot07 (Reply 78):
right.
But YOU tell that to TV, the press, the minister, and all on a.net who all want results yesterday !

Quoting anfromme (Reply 85):
Your point being? Are you trying to use the families of the victims as an excuse for the howling that's going on here about how slow progress has been?

Respectfully, I haven't heard much, if any, "howling" about the slow progress in finding the wreckage. Any "howling" I heard, my own "howling" included, has been discussing the slowness in initially finding the point where the plane went in the drink, with an eye toward at least giving any miracle survivors one last chance. The current system means that the passengers die of exposure, even if they make it out of the aircraft.

At least if y'all are going to be derisive and dismissive of people's concerns, it would be courteous and yes - open-minded - to make a better attempt to understand the point of those concerns.

kanban · Sat Jan 10, 2015 7:09 pm

most of the people critical of the operation do not live near the site nor are aware of the weather or currents.. the crews are doing the best they can under the circumstances.

For those who insist on carrying the assumed emotional burden for the families.. take a look at your motives.. do you carry on the same way for other accident victims families.. I don't see you commenting in the non av section when a ferry sinks.

SimonDanger · Sat Jan 10, 2015 7:17 pm

Quoting anfromme (Reply 85):
Quoting SimonDanger (Reply 84):
And the families of the victims, whom we are repeatedly told read this site, and whom deserve our care, concern and respect as we discuss this unfortunate accident, will they be accused of similar "howling" as well?

Quoting anfromme (Reply 85):
Your point being? Are you trying to use the families of the victims as an excuse for the howling that's going on here about how slow progress has been?

No. Quite the opposite. I was trying to point out that some of the scolds on this site want to belittle those of us who have been frustrated by the inabilty to find an $85 million piece of high technology in this day and age, and yet the families of this flight are paradoxically granted an infinite amount of inpatience. We all want the same thing, though for different reasons. I want the airline industry to be fed up with these lengthy searches, and the families want closure for their loved ones.

kanban · Sat Jan 10, 2015 7:20 pm

Quoting SimonDanger (Reply 88):

famous fortune cookie "when your expectations are not met, lower them"

MD11Engineer · Sat Jan 10, 2015 7:30 pm

Quoting md80fanatic (Reply 66):
Even on receive only, the longer the wire (the closer to resonance) the more the gain, which equates to how much deeper the submarine can be and still be able to pull the signal from the muck and background static.

Perhaps a better implementation would be a VLF receiver (long wire) which would "listen" for a wake-up sequence transmitted from SAR boats searching above. Once received the audio frequency pinger could be started, with full battery power as opposed to having it pinging away with no one in range to hear it ... until the search teams arrive of course.

Quoting md80fanatic (Reply 80):
The left side of the above cropping from a previous image shows what looks like the aft emergency exit door frame. The emergency slide cover, and the exit sign is visible. I would assume that door frames are probably the most hearty part of the pressure vessel so it should take relatively more force to deform it. That door frame has been doubled over completely and I cannot see a situation where a flat, bottom down impact could cause such a deformation. It really looks like this piece would need to impact the water nearly upside down to account for such a shape. Part location reference can be established from the image below by comparing livery colors around the door frame.

No,it is not an emergency exit door frame, but the frame of the (most likely) aft entry door, seen from the bottom up. You can see the stainless steel scuff plate (lower sill) facing the man looking up. Overwing exits don't have them, since they don't get approached by stairs.On the other end you can make out the guide rod, which would be in the forward upper corner of the door frame. To the right I can make out some pieces of the aft pressure bulkhead with two wire feedthroughs. Parts of the aft galley ceiling are also visible.

Jan
In the picture in post # 68 the hoisting balloon can be seen.

md80fanatic · Sat Jan 10, 2015 7:37 pm

The section of the A320 that we are looking at in my previous cropping above ...

Thank you md11engineer, that was what I meant. The picture above looks like that, as an entry door, is not available for pax to enter through (looks like a galley or lavatory) so I mistakenly called it an emergency exit. My apologies.

I agree about the aft bulkhead, that has been bothering me since ... and I am trying hard not to think this way ... the damage to this area, the door frame/bulkhead could also be caused by a particularly strong force from -inside- the aircraft.

cpw · Sat Jan 10, 2015 7:56 pm

...

Quoting md80fanatic (Reply 91):
could also be caused by a particularly strong force from -inside- the aircraft.

Any chance a cart loaded with ice and cans of pop coming loose during severe turbulence could damage the pressure bulkhead and cause it to rupture? This comes to mind... http://en.wikipedia.org/wiki/Japan_Airlines_Flight_123

namezero111111 · Sat Jan 10, 2015 8:10 pm

Quoting cpw (Reply 92):

Well, that cart would have to hit the rear with quite some force and penetrate the cabin wall/insulation (which will absorb quite a bit of energy).
Of course you could damage a bulkhead if hitting it with something with enough force, but I find the postulated scenario unlikely.

[Edited 2015-01-10 12:19:04]

[Edited 2015-01-10 12:19:18]

MD11Engineer · Sat Jan 10, 2015 8:10 pm

Quoting md80fanatic (Reply 91):
The section of the A320 that we are looking at in my previous cropping above ...

You can see the same wire feedthrough on the left upper part of your new picture. It is the heavy wire bundle of the APU feeder cables. You can also see the door frame we were ooking at with th wreck from the inside (with cosmetic lining panels missing) The guide rod for the door is visible in the upper right corner of the door cutout. The aft galley hasn't been installed yet but the floor has already been sealed against water ingress. You can see the lower galley attachment fittings sticking out of the floor. The upper corners of the aft galley get attached to the massive structure on top by rods.

The aft entry door is actually used by passengers when they board or disembark using stairs instead on one single jetway attached to the forward entry door.

Jan

md80fanatic · Sat Jan 10, 2015 8:28 pm

Quoting md11engineer (Reply 94):
You can see the same wire feedthrough on the left upper part of your new picture. It is the heavy wire bundle of the APU feeder cables.

I thought it may have been the two hoses seen near the aft port corner of the floor panel. In the debris picture they look like the hoses normally seen attached to an air conditioning compressor. The position of the hoses being near the top in the debris picture, considering the exit door frame being folded over completely, the bulkhead might also have been folded over proportionately.

Kaiarahi · Sat Jan 10, 2015 8:30 pm

Quoting SimonDanger (Reply 84):
And the families of the victims, whom we are repeatedly told read this site, and whom deserve our care, concern and respect as we discuss this unfortunate accident, will they be accused of similar "howling" as well?

Did I say anything of the kind?

Quoting SimonDanger (Reply 88):
No. Quite the opposite. I was trying to point out that some of the scolds on this site want to belittle those of us who have been frustrated by the inabilty to find an $85 million piece of high technology in this day and age

The ADS-B feed provided the same information as any of the "real time" data feeds postulated here would have.

Quoting SimonDanger (Reply 88):
I want the airline industry to be fed up with these lengthy searches

10 days, hampered by weather and sea conditions. 2 more days to recover this part of the wreckage, hampered by weather and sea conditions. Do you have a solution for controlling the weather?

md80fanatic · Sat Jan 10, 2015 8:32 pm

Quoting namezero111111 (Reply 93):

Quoting cpw (Reply 92):

Well, that cart would have to hit the rear with quite some force and penetrate the cabin wall/insulation (which will absorb quite a bit of energy).
Of course you could damage a bulkhead if hitting it with something with enough force, but I find the postulated scenario unlikely.

I don't think anything designed to be inside the aircraft could cause this kind of damage. My thoughts were more along the lines of something that shouldn't have been there, like explosives.

lancelot07 · Sat Jan 10, 2015 8:40 pm

Quoting cpw (Reply 92):
Any chance a cart loaded with ice and cans of pop coming loose during severe turbulence could damage the pressure bulkhead and cause it to rupture? This comes to mind... http://en.wikipedia.org/wiki/Japan_Airlines_Flight_123

That accident was caused by fatigue after a faulty repair. Nothing of that kind is known about the plane involved here.

Quoting md80fanatic (Reply 91):
I agree about the aft bulkhead, that has been bothering me since ... and I am trying hard not to think this way ... the damage to this area, the door frame/bulkhead could also be caused by a particularly strong force from -inside- the aircraft

a possibility, yes. But it might be caused by impact.
I wonder how the rudder can break (see photo in #68). A small part at the lower end is missing, the larger part is still attached to the fin.

MD11Engineer · Sat Jan 10, 2015 8:55 pm

Quoting md80fanatic (Reply 95):
Quoting md11engineer (Reply 94):
You can see the same wire feedthrough on the left upper part of your new picture. It is the heavy wire bundle of the APU feeder cables.

I thought it may have been the two hoses seen near the aft port corner of the floor panel. In the debris picture they look like the hoses normally seen attached to an air conditioning compressor. The position of the hoses being near the top in the debris picture, considering the exit door frame being folded over completely, the bulkhead might also have been folded over proportionately.

IIRC (it is a while ago since I worked on an A320, but we have one sitting in our hangar with the interior stripped out, so I can have a look next week) these two hoses are water lines for the galley coffee makers and boilers. The drain line for the galley sinks should be the little gray pipe sticking out from the floor towards the far side of the bulkhead
No airconditioning compressors on the A320, the conditioned air comes from two expander turbine-compressor aircon packs, and would go to the aft galley through a duct in the ceiling (not visible in the picture due to cropping). The thick pipes sticking out behind the floor in the middle of the pressure bulkheadv(the ones covered with an orange rag) are IIRC ventilation exhaust pipes to draw food smells etc. from the galleys through a fan beneath the floor, which exhausts close to the outflow valve in section 18 (similar to your kitchen smoke hood).

The two big round things on the right side of the pressure bulkhead (I always use aircraft right or left, looking forward into direction of flight) are the cabin overpressure valves.

Jan

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