AF 447 Search to resume
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Chris Scott, color me blabbymouthed broad but I'm going to riff a little. The superposition of the actual aircraft size images on the debris field was eye opening.
What we see, I suspect, is a very broken up, shredded airplane. We have pieces of different shape, weight, and buoyancy. The debris field has probably a shape more related to the currents and shapes of pieces as they fell. Engines and possibly landing gear will be least affected by currents or "flutter" effects. Small relatively light pieces will flutter more on their way down and be more subject to the current moving them slightly.
I'd bet the overall orientation reflects some prevailing current involved. And the width would be related to how much the pieces fluttered as much as it's a function of the current.
If that's accurate then one end has the heavy stuff. And the rest is graded by how much "flutter" and current moved them away from falling straight down. So I'd expect some "astonishing" juxtapositions of pieces.
We're not seeing an airplane there. We're seeing thousands of pieces of airplane all different sizes, shapes, and weights all dropped at nearly the same place into an impressively deep bathtub.
Edit: (Grin - I see BOAC got there before I did. I didn't think he'd make it after saying the plane would sort of fly equally well underwater.)
What we see, I suspect, is a very broken up, shredded airplane. We have pieces of different shape, weight, and buoyancy. The debris field has probably a shape more related to the currents and shapes of pieces as they fell. Engines and possibly landing gear will be least affected by currents or "flutter" effects. Small relatively light pieces will flutter more on their way down and be more subject to the current moving them slightly.
I'd bet the overall orientation reflects some prevailing current involved. And the width would be related to how much the pieces fluttered as much as it's a function of the current.
If that's accurate then one end has the heavy stuff. And the rest is graded by how much "flutter" and current moved them away from falling straight down. So I'd expect some "astonishing" juxtapositions of pieces.
We're not seeing an airplane there. We're seeing thousands of pieces of airplane all different sizes, shapes, and weights all dropped at nearly the same place into an impressively deep bathtub.
Edit: (Grin - I see BOAC got there before I did. I didn't think he'd make it after saying the plane would sort of fly equally well underwater.)
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Shadoko:
Well, I may as well chime in (again).
Airspeed discrepancy in turb. Icing. Pilots quickly realise a stall is in progress and 'Alt law' in force. They pitch down to maintain airspeed, and manually control the throttles. Descending through the weather, they in theory may have levelled off a few times, but any pitch down would prodice a high-ish rate of decent. If the wings were iced then is that not akin to popping the lift dumpers?
So whatever the 'downward' speed, the aircraft still has forward motion, but despite recovering to 'level' flight a few times, the iced wings overcome available thrust and the drop cannot be reduced much.
Could it actually be described as a very hard ditching, with forward velocity possibly only about 250-300% of downward velocity IE still 'realtively fast in direction' but not to maintain flight.??
In fact, I can't imagine this aircraft falling from 35000' to 0 keeping a "normal" attitude all along (and not attached passengers remaining in their seats*). Adding a storm, is this "flat" fall truly possible ?
Airspeed discrepancy in turb. Icing. Pilots quickly realise a stall is in progress and 'Alt law' in force. They pitch down to maintain airspeed, and manually control the throttles. Descending through the weather, they in theory may have levelled off a few times, but any pitch down would prodice a high-ish rate of decent. If the wings were iced then is that not akin to popping the lift dumpers?
So whatever the 'downward' speed, the aircraft still has forward motion, but despite recovering to 'level' flight a few times, the iced wings overcome available thrust and the drop cannot be reduced much.
Could it actually be described as a very hard ditching, with forward velocity possibly only about 250-300% of downward velocity IE still 'realtively fast in direction' but not to maintain flight.??
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Wreck interpretation
Chris Scott,
I'm beginning to regret saying anything. As you can see from the dispute about the object I thought might be the cockpit remains, its dangerous to make any assumptions from just one, third or fourth hand sonar picture. The point of my story about the technician on Odin Finder (a survey ship I first used for the Ark Royal) is that there is a big change in behaviour once objects make the transition from air to water, and I have to agree with the essence of BOAC's point.This was one of the reasons why I disagreed with mm43's view that the debris field would be realtively compact. Given the depth of water I think I said that I expected it to be spread over a kilometre. As I also said I was wrong.
What we have, publicly at least is a very rough indication of the location of the debris field, and an accurate last known position. I gather that a lot of people thought that the aircraft would have travelled farther from the last known position than it appears to have done. This obviously was the planning assumption behind the first searches. So there is a huge unknown here. What is also unknown is whether the aircraft remained substantialy intact after its impact with the surface,( I know the fin and parts of the galley and crew quarters were recovered, I'm not sure what else was) how long the wreckage remained on the surface before starting to sink and how it's break up was affected by the various currents it encountered in its descent, as well as what attitude it had adopted before its impact with the seabed, which would have cause further damage. Even the recovery of the flight data recorder and the cockpit voice recorder won't tell us much about that part of the aircraft's journey. mm43 made the point that the location of the engines in relation to the rest of the debris would be important in providing answers to some of these questions. Can I ask if it is safe to assume that they would have seperated on impact in all circumstances?
I'm beginning to regret saying anything. As you can see from the dispute about the object I thought might be the cockpit remains, its dangerous to make any assumptions from just one, third or fourth hand sonar picture. The point of my story about the technician on Odin Finder (a survey ship I first used for the Ark Royal) is that there is a big change in behaviour once objects make the transition from air to water, and I have to agree with the essence of BOAC's point.This was one of the reasons why I disagreed with mm43's view that the debris field would be realtively compact. Given the depth of water I think I said that I expected it to be spread over a kilometre. As I also said I was wrong.
What we have, publicly at least is a very rough indication of the location of the debris field, and an accurate last known position. I gather that a lot of people thought that the aircraft would have travelled farther from the last known position than it appears to have done. This obviously was the planning assumption behind the first searches. So there is a huge unknown here. What is also unknown is whether the aircraft remained substantialy intact after its impact with the surface,( I know the fin and parts of the galley and crew quarters were recovered, I'm not sure what else was) how long the wreckage remained on the surface before starting to sink and how it's break up was affected by the various currents it encountered in its descent, as well as what attitude it had adopted before its impact with the seabed, which would have cause further damage. Even the recovery of the flight data recorder and the cockpit voice recorder won't tell us much about that part of the aircraft's journey. mm43 made the point that the location of the engines in relation to the rest of the debris would be important in providing answers to some of these questions. Can I ask if it is safe to assume that they would have seperated on impact in all circumstances?
Last edited by Jetdriver; 15th Apr 2011 at 23:10.
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Originally Posted by Mr Optimistic
Forgive the noob question on sonar, but is the image produced on a single pass, eg from the rov above the eastern edge of the lane, or is it the addition of two half pictures, one from the east and one from the western pass ? Also what would the effective lateral beam width be, ie the length of image producted by a point object (are the N/S 'smearings' a reflection of pulse width and not debris dimension ?). Noting its a jpeg, any need to be careful about compression artefacts ?
auv-ee
Autonomous Undewater Vehicle-Electronics Engineer ? Thanks. Wondered how it was done. Apologies for not having read your posting first time around. Any chance of a deconvolution algorithm ?
Last edited by Mr Optimistic; 15th Apr 2011 at 12:40. Reason: lame attempt at humour
In a jocular vein ...
Well, they were fresh out of Rio ... 
But regarding things falling in water for about two and a half miles.
IF (big if) the wings maintain their general shape at impact (even if shearing off from fuselage at impact) then during a two and a half mile excursion down (after a brief dwell time at the surface as the internal cavities fill with water and buoyancy is eventually overcome) I'd expect that eventually, with tumbling action, the wing would take on a generally "tip down root up" alignment as the entire cavity fills with water. (Yes, there is probably fuel trapped within fuel tanks that would render the general buoyancy of the wing greater than other pieces as they tumble downward).
I'd expect the wings, were they separated from the fuselage, to be more, not less, subject to currents under the surface than most of the rest of the aircraft.
As I have not been able to view quite a number of the images posted (filter issues on my browser, I suspect), do they depict the wings still attached to, or separated from, the fuselage? Or, am I gettting ahead of it all, and resolution not sufficient to determine same?
EDIT: I had a look at the A330-200 fuel system (outline) from a 1999 era document here.
As I understand the flow, engines are fed from wing tanks (inner) and wing tanks replenished by the, outer, trim, and center tanks as fuel depletes over time. (Do I understand that correctly? It is a sketchy summary of the fuel system.)
(*Scratches head.* If not, then perhaps the flow is out to the engines from the center tank (via plumbing and pumps) and center tank replenished from all other tanks ...) Not all that important, but of interest to consider which cavities / tanks were emptied or low on fuel at that point in the flight, and how that would influence downward trajectory toward the sea bed.
Were they holding a dance in the aisles for entertainment?
But regarding things falling in water for about two and a half miles.
IF (big if) the wings maintain their general shape at impact (even if shearing off from fuselage at impact) then during a two and a half mile excursion down (after a brief dwell time at the surface as the internal cavities fill with water and buoyancy is eventually overcome) I'd expect that eventually, with tumbling action, the wing would take on a generally "tip down root up" alignment as the entire cavity fills with water. (Yes, there is probably fuel trapped within fuel tanks that would render the general buoyancy of the wing greater than other pieces as they tumble downward).
I'd expect the wings, were they separated from the fuselage, to be more, not less, subject to currents under the surface than most of the rest of the aircraft.
As I have not been able to view quite a number of the images posted (filter issues on my browser, I suspect), do they depict the wings still attached to, or separated from, the fuselage? Or, am I gettting ahead of it all, and resolution not sufficient to determine same?
EDIT: I had a look at the A330-200 fuel system (outline) from a 1999 era document here.
As I understand the flow, engines are fed from wing tanks (inner) and wing tanks replenished by the, outer, trim, and center tanks as fuel depletes over time. (Do I understand that correctly? It is a sketchy summary of the fuel system.)
(*Scratches head.* If not, then perhaps the flow is out to the engines from the center tank (via plumbing and pumps) and center tank replenished from all other tanks ...) Not all that important, but of interest to consider which cavities / tanks were emptied or low on fuel at that point in the flight, and how that would influence downward trajectory toward the sea bed.
Last edited by Lonewolf_50; 15th Apr 2011 at 12:57.
Given the rough ride surely the signs were on and every one seated ? Don't know what proportion of CC identified but can't trust the 'it all happened so fast theory'. Some pretty big stuff escaped the wreckage. Surprising that objects with such different 'ballistic coefficients' arrived in more or less the same place after a 4000m descent and that the field has such symmetry. However, there must be a reason..........
As I note a lot of discussion here about aircraft parts sinking thousands of feet to the seabed I thought taht I would offer some ancedotal evidence I came across years back.
Apparently the US Navy was doing a recovery years ago of an F14 that was sitting about 10000 ft down at the bottom. Their submersibles at the time were manned and even after locating the scattered wreckage they would have a difficult time going from one end of the field to the other, since they really didn't know precisely (enough for vision) which way they were heading and where the ends of the field were.
The mother ship with its gear did know where it was on the surface but not where the submersible was. I'm sure today the technology is a lot different. What they did back then was to take a whole bunch of 55 gallon drums, paint numbers on them, then cut holes in the drums then align the mother ship in a line somewhere (they hoped) over the expected debris field and then put the drums over the side of the ship at time intervals while underway.
The drums sank to the bottom (10000 ft down) and presto even with the various currents they were found later by the submersible strewn out roughly in a line that transversed the debris field (in a random drection).
Now I'll leave it to the reader to draw any inferences they care from that experiment
Apparently the US Navy was doing a recovery years ago of an F14 that was sitting about 10000 ft down at the bottom. Their submersibles at the time were manned and even after locating the scattered wreckage they would have a difficult time going from one end of the field to the other, since they really didn't know precisely (enough for vision) which way they were heading and where the ends of the field were.
The mother ship with its gear did know where it was on the surface but not where the submersible was. I'm sure today the technology is a lot different. What they did back then was to take a whole bunch of 55 gallon drums, paint numbers on them, then cut holes in the drums then align the mother ship in a line somewhere (they hoped) over the expected debris field and then put the drums over the side of the ship at time intervals while underway.
The drums sank to the bottom (10000 ft down) and presto even with the various currents they were found later by the submersible strewn out roughly in a line that transversed the debris field (in a random drection).
Now I'll leave it to the reader to draw any inferences they care from that experiment
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Ah. Lone, the pictures show a 200 meter high by 600 meter wide major field of debris with a few outriders. The field is vaguely whale shaped with about 300 meters by 150 meters of dense debris and a lump out maybe 300 meters to the fat end of the whale shape and a little knife shape sticking out from the middle of the whale and another short bright line of something maybe 400 to 500 meters away on the same side as the "knife". Compare that with the size of the plane itself and you can easily see this isn't well related to the size of the plane. It fits within the debris field with a lot of spare no matter which way you turn the plane. (The whale points roughly to the East for its "head" end. I bet that's where the engine is with the rest being where the smaller pieces fell. So the currents seen were predominantly east to west. That's a surmise, though. I'm no expert in this.)
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half an hour sinking
BOAC: Hydrodynamics work pretty much as aerodynamics at low speeds. A wing will produce a force of some sort.
water is 1000 times heavier than air, sqrt 1000= 31.6
so if it was fallen through the air with 75 m/s it will sink under water with a dimension of 75/31,6=2,4 m/s
and so it will need around 4000/2,4=1666 sec (half an hour!) to reach the sea bottom
a very long time to turtle around
grity
p.s. again my question: what else did wie see on the underwater picture with the wing??
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The original pictures are available on Sea search ops : wreckage images - I guess the highest quality?
Are the 2 images both the same engine?
Are the 2 images both the same engine?
For the Titanic, estimates of terminal speeds between 20 and 60 mph are talked about. Judging by the photo's of the engines which look chewed up but are not buried in the sediment wasn't too high a speed. 20 mph would give less than 9 minutes.
60mph is awfully fast. Fastest nuke sub (Russian) barely reached 45kn. Average is in the 25 to 30kn range with big powerfull propellers and hydrodynamic shape...
Sea-level Impact vs Sea-bed Impact
Thank you swordfish41,
Apologies if my series of questions have the tone of a precocious boy in class... Think you've answered all them, except:
"Could the laterally-lying pieces extending northwards include a wing box?"
Last night (APR14/2120z), with his excellent enlarged image, mm43 posted:
"....If this is the case, then the heading at impact was around 070°T."
In the wee-small hours here in Blighty, I interpreted "impact" as being what I call the "sea-level impact" (end of flight). I now realise he was probably referring to the sea-BED impact...
Does everyone agree that the answer to my question
"Would the debris field alignment (approximately 070/250) necessarily be roughly indicative of the heading at sea-level impact...?"
is something like: "No, Scott, think again – (stupid boy)." ?
Apologies if my series of questions have the tone of a precocious boy in class... Think you've answered all them, except:
"Could the laterally-lying pieces extending northwards include a wing box?"
Last night (APR14/2120z), with his excellent enlarged image, mm43 posted:
"....If this is the case, then the heading at impact was around 070°T."
In the wee-small hours here in Blighty, I interpreted "impact" as being what I call the "sea-level impact" (end of flight). I now realise he was probably referring to the sea-BED impact...
Does everyone agree that the answer to my question
"Would the debris field alignment (approximately 070/250) necessarily be roughly indicative of the heading at sea-level impact...?"
is something like: "No, Scott, think again – (stupid boy)." ?
Fuel Distribution
Lonewolf50,
As you still seem to be waiting for an answer to your fuel-tank management question, and with A330-drivers PJ2 and CONF_iture apparently AWOL, I'll try and shed some non-definitive, tentative light (thanks for that link).
Fuel is fed to the engines from the inner wing-tanks. For efficiency, in the cruise the CG is normally adjusted aft of the ideal for take-off and landing. On all A330s, the tailplane trim-tank helps, but I'll ignore that for the moment. This A330-200 also has a centre tank. This is, broadly speaking, forward of the wings, so is generally only used if the crew needs more than full-wings (71.7T) for the flight. In flight, it is emptied first, into the inners, which may also help with wing-bending relief. (Fuel will never be transferred from wings to centre tank.) In this case, the take-off fuel was only 70.4T, so the centre tank would have been empty throughout. In the climb, some fuel is normally transferred to the tailplane trim-tank, unless it's already full, pushing the CG aft by a suitable amount.
Wing-bending relief is also achieved by retaining full outer wing-tanks until the fuel in the inners is fairly low. When there's about 7T (tonnes) between the 2 inners, the 2 outers transfer their combined 5.7T into them. This does not happen until the trim tank has been emptied (via the inners). So at this point there is about 12.7T fuel remaining (< 3 hrs).
Normally, all this is controlled automatically (no grizzled flight-engineer...).
At the LKP, with nearly 7 hrs still to go to CDG, the fuel distribution should have been roughly as follows:
Tailplane full (4.9T) or part-full; *
Centre empty;
Inners part-full; **
Outers full (each 2.8T);
Vent Tanks empty (outboard of the Outers).
* According to the zero-fuel CG, and the current fuel distribution elsewhere, to optimise CG (relative to MAC).
** They were nearly full (all but ~0.6T each) at take-off, and would have been depleted to the extent of the total fuel burned (in 3:41 of flight) PLUS whatever was in the Trim tank at the time. (I think it would have been empty on departure.)
Hope this helps,
Chris
As you still seem to be waiting for an answer to your fuel-tank management question, and with A330-drivers PJ2 and CONF_iture apparently AWOL, I'll try and shed some non-definitive, tentative light (thanks for that link).
Fuel is fed to the engines from the inner wing-tanks. For efficiency, in the cruise the CG is normally adjusted aft of the ideal for take-off and landing. On all A330s, the tailplane trim-tank helps, but I'll ignore that for the moment. This A330-200 also has a centre tank. This is, broadly speaking, forward of the wings, so is generally only used if the crew needs more than full-wings (71.7T) for the flight. In flight, it is emptied first, into the inners, which may also help with wing-bending relief. (Fuel will never be transferred from wings to centre tank.) In this case, the take-off fuel was only 70.4T, so the centre tank would have been empty throughout. In the climb, some fuel is normally transferred to the tailplane trim-tank, unless it's already full, pushing the CG aft by a suitable amount.
Wing-bending relief is also achieved by retaining full outer wing-tanks until the fuel in the inners is fairly low. When there's about 7T (tonnes) between the 2 inners, the 2 outers transfer their combined 5.7T into them. This does not happen until the trim tank has been emptied (via the inners). So at this point there is about 12.7T fuel remaining (< 3 hrs).
Normally, all this is controlled automatically (no grizzled flight-engineer...).
At the LKP, with nearly 7 hrs still to go to CDG, the fuel distribution should have been roughly as follows:
Tailplane full (4.9T) or part-full; *
Centre empty;
Inners part-full; **
Outers full (each 2.8T);
Vent Tanks empty (outboard of the Outers).
* According to the zero-fuel CG, and the current fuel distribution elsewhere, to optimise CG (relative to MAC).
** They were nearly full (all but ~0.6T each) at take-off, and would have been depleted to the extent of the total fuel burned (in 3:41 of flight) PLUS whatever was in the Trim tank at the time. (I think it would have been empty on departure.)
Hope this helps,
Chris
Last edited by Chris Scott; 16th Apr 2011 at 09:57. Reason: Clarifications. Typos. Note(*) extended. Para2 improved.
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Given that all studies show weak and rather random sea currents, I would agree. Nevertheless, I would not bet on east to west vs. west to east direction... That bird was obviously way out of control!
Lonewolf, JD-EE, in searching for some idea of the wreckage condition and layout, the China Airlines A300 stall accident at Nagoya in April of 1994 may be of interest.
The aircraft stalled on short final, (to keep this short, the reasons for the accident are in the report, here), and impacted in essentially the same attitudes as the BEA has described.
From the report (translated from the Japanese):
The impact would be essentially the same, but the hard land surface in the Nagoya accident permitted a longer/wider distribution of wreckage with perhaps far more secondary damage as parts collided with each other and ground objects before coming to rest.
A water impact, as has been pointed out, would be as hard, but once the initial impact had shattered the aircraft, the high inertial energy vertical and horizontal components of the resulting wreckage would quickly be absorbed by the water, remaining largely together in a collected mass, their individual weight and buoyancy then acting as a distribution filter, slowly separating heavier from lighter parts as they descended and were affected by whatever currents there were, creating the pattern observed in the AUV image, (as observed by others, JD-EE in particular has described quite well above). I think a general conclusion may be made as to direction of flight. All parts descending through the same "water column" (roughly), would be affected in the same general manner.
And it doesn't seem as though some of the larger parts have, due to their shape, etc, "flown/glided" down (as some have observed I know), but rather may have "glided locally" and largely together, settling as described, by weight and buoyancy as a group.
Regardless of surface, the Nagoya accident shows quite clearly what happens to the fuselage in a high-vertical-speed impact - it collapses and, we may surmize, the substantial volume of air thus instantly compressed would escape through the breaks which would likely be at the mid-line of the fuselage as viewed on-end, with fractures at those fuselage sections we have seen before...behind the cockpit, just in front of and just behind the wing-box, and just ahead of the vertical/horizontal stabilizers and pressure bulkhead, (the section shown being manufactured in Machaca's superb photographs at post #3170), all permitting large sections of the cabin to be ejected relatively cleanly, without more than glancing collisions with other parts, leaving them in the condition we see in the collected wreckage.
Chris, just spotted your note to Lonewolf...in my recollection of the system, that was a nice description of how it works. Bit different than the DC8...
The aircraft stalled on short final, (to keep this short, the reasons for the accident are in the report, here), and impacted in essentially the same attitudes as the BEA has described.
From the report (translated from the Japanese):
"3.1.4.1 From the DFDR records, it is estimated that the aircraft stalled, then descended steeply with wildly changing roll angle, and impacted the ground.
The spot where the aircraft hit the ground was an unpaved, flat landing area. There were marks left on the ground surface that clearly identified those portions of the aircraft which had hit the ground. From the shapes of the marks and these positional relationships as well as the condition of destroyed landing gears, it is inferred that on impact, the aircraft was in a somewhat left-wing down, nose-up attitude, and was in an almost level attitude." - p67,
The spot where the aircraft hit the ground was an unpaved, flat landing area. There were marks left on the ground surface that clearly identified those portions of the aircraft which had hit the ground. From the shapes of the marks and these positional relationships as well as the condition of destroyed landing gears, it is inferred that on impact, the aircraft was in a somewhat left-wing down, nose-up attitude, and was in an almost level attitude." - p67,
A water impact, as has been pointed out, would be as hard, but once the initial impact had shattered the aircraft, the high inertial energy vertical and horizontal components of the resulting wreckage would quickly be absorbed by the water, remaining largely together in a collected mass, their individual weight and buoyancy then acting as a distribution filter, slowly separating heavier from lighter parts as they descended and were affected by whatever currents there were, creating the pattern observed in the AUV image, (as observed by others, JD-EE in particular has described quite well above). I think a general conclusion may be made as to direction of flight. All parts descending through the same "water column" (roughly), would be affected in the same general manner.
And it doesn't seem as though some of the larger parts have, due to their shape, etc, "flown/glided" down (as some have observed I know), but rather may have "glided locally" and largely together, settling as described, by weight and buoyancy as a group.
Regardless of surface, the Nagoya accident shows quite clearly what happens to the fuselage in a high-vertical-speed impact - it collapses and, we may surmize, the substantial volume of air thus instantly compressed would escape through the breaks which would likely be at the mid-line of the fuselage as viewed on-end, with fractures at those fuselage sections we have seen before...behind the cockpit, just in front of and just behind the wing-box, and just ahead of the vertical/horizontal stabilizers and pressure bulkhead, (the section shown being manufactured in Machaca's superb photographs at post #3170), all permitting large sections of the cabin to be ejected relatively cleanly, without more than glancing collisions with other parts, leaving them in the condition we see in the collected wreckage.
Chris, just spotted your note to Lonewolf...in my recollection of the system, that was a nice description of how it works. Bit different than the DC8...
Last edited by Jetdriver; 15th Apr 2011 at 23:08.
At the time of the accident, with nearly 7 hrs still to go to CDG, the fuel distribution should have been as follows: Tailplane full (4.9T) or part-full; * Centre empty; Inners part-full; ** Outers full (each 2.8T); Vent Tanks empty (outboard of the Outers).
Thanks very much, I had it a bit arse backwards there.
The thought I had of the wing tanks having a lot of fuel (in combination) seems roughly right. I'll guess that the fuel tanks suffered trauma, and fuel escaped both as parts first floated just after impact, and then eventually began to sink. I have an idea beginning to form that any fuel slick might not have been very large ...
PJ2:
Thanks as well for the explanation, and the link to the Nagoya crash.
A water impact, as has been pointed out, would be as hard, but once the initial impact had shattered the aircraft, the high inertial energy vertical and horizontal components of the resulting wreckage would quickly be absorbed by the water, remaining largely together in a collected mass, their individual weight and buoyancy then acting as a distribution filter, slowly separating heavier from lighter parts as they descended and were affected by whatever currents there were, creating the pattern observed in the AUV image, (as observed by others, JD-EE in particular has described quite well above). I think a general conclusion may be made as to direction of flight. All parts descending through the same "water column" (roughly), would be affected in the same general manner.
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@mm43; pickyPerkin; Chris Scott
if we press the sidescan picture in the hight to 14% it lock much more as a view to a debrisfield....... smal parts to the left bigger one to the right
sortet by the different falling time and a slow deeper water current?
grity
if we press the sidescan picture in the hight to 14% it lock much more as a view to a debrisfield....... smal parts to the left bigger one to the right
sortet by the different falling time and a slow deeper water current?
grity
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sensor validation
My guess would be that we are looking at one engine with a slightly different camera orientation (height, distance and lighting) in the two photos. The clue to me is the piping that extends outward and downward to the seabed. The chances of that being the same for both engines would be very great odds indeed.
Are the 2 images both the same engine?