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AF 447 Search to resume

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AF 447 Search to resume

Old 4th Apr 2011, 19:13
  #2961 (permalink)  
 
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Originally Posted by damirc
Interesting...

I find it rather interesting to notice, that the wreckage is generally spread east-west/west-east (flighpath should've been NNE). Unxpected.

(in reference to http://www.bea.aero/fr/enquetes/vol....sn109a700m.jpg)
Consider three factors that would arrest momentum in the NNE direction of the flight as it was supposed to be flying at 30,000+ feet.

1. Aircraft was most likely not in controlled flight (more likely stalled). Had the stall been a simple "nose falls stall" it would a) have been more recoverable and b) likely been arrested before impact with the sea during the five mile plummet.

2. An upset/stall is likely to develop a rotational feature. The more the aircraft rotates, or has a post stall gyration, the less likely "initial heading" can be preserved during X rotations from 30,000+ feet to 0 feet.

3. Debris field has been subject to various oceanic influence, which were not necessarily aligned with the direction of flight. Unlike a crash that hits the ground, final resting place of this aircraft after impact will move ... in this case, due to both wind and water mass movements.

Put another way, I'd be stunned if the debris field were to have coincided with the selected course (NNE) that was to take the flight to Paris. Had they been able to maintain course/heading, I doubt they'd have crashed at all.
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Old 4th Apr 2011, 19:21
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1. Aircraft was most likely not in controlled flight (more likely stalled). Had the stall been a simple "nose falls stall" it would a) have been more recoverable and b) likely been arrested before impact with the sea during the five mile plummet.
Well, the latest (Dec 2009 IIRC) report does seem to indicate the aircraft was near-wing level upon water contact.

3. Debris field has been subject to various oceanic influence, which were not necessarily aligned with the direction of flight. Unlike a crash that hits the ground, final resting place of this aircraft after impact will move ... in this case, due to both wind and water mass movements.
Point taken... still was the first thing that looked very odd. I would suspect that even upon water contact some forward moment (and some was supposed to have been present judging from material analysis) would've remained and would have formed at least the basic "spread" before floating to the seabed. But yes, I see your point. Too little info to make an (educated) guess.

Put another way, I'd be stunned if the debris field were to have coincided with the selected course (NNE) that was to take the flight to Paris. Had they been able to maintain course/heading, I doubt they'd have crashed at all.
Fully agree on that point. Too confused about both the location and the spread.

D.
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Old 4th Apr 2011, 19:21
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Lets hope the boxes are found and closure finally brought to this tragic incident.
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Old 4th Apr 2011, 19:38
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Question regarding the tyres in the photos. I am surprised they are not crushed / squashed by the pressure at that depth.
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Old 4th Apr 2011, 19:50
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Looking closely at one of the tyres one can see that it has been ruptured near the rim. I assume it has returned to its uninflated shape..but is full of water at ambient (4000m) pressure.
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Old 4th Apr 2011, 19:51
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Machaca, in the overlay to mm43's graphic, the location is probably to the west of the arrow tip. mm43 carefully drew the first day's aerial search grid (the yellow box) along the flight path, and unless the Brazilians were blind, the location is probably several kilometers to the west of that first search grid.

As has been discussed for many months, the subsequent searches in the several days following were to the right of that yellow box (i.e., to the east) along the flight path.

From an academic standpoint, it will be interesting to learn the reasons for the current and drift reconstructions having been off.

Last edited by SaturnV; 4th Apr 2011 at 20:05.
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Old 4th Apr 2011, 19:53
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Interesting that the drift was not as chaotic as thought. Compare MM43's map at post 911 of this thread and this link below. Looking at the phase three search area it is a shame that they took a "bite out of the sandwich" in the search area. Understandable based on duration of flight from LKP, track deviation, etc. I guess the lesson is start at LKP and head out despite how smart we all think we are.

http://www.bea.aero/en/enquetes/flig...hes.en.mer.pdf
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Old 4th Apr 2011, 20:02
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i would epect the tires to only lose their air when pressure was great enough to break the rubber seal with the rims, but not explode from the pressure.

I haven't read the BEA report but from what we've seen so far we can determne that:
- it was a relatively low speed impact (somewhere less than supersonic) with the ocean surface as the airframe wasn't broken into tiny bits
- if all sunken major airframe parts are recovered in that small area then those airframe parts were likely connected at impact rather than seperating at altitude,
- the fuselage was opened at some point (upon impact I expect) because the previously recovered galley came from within the cabin,
- we don't know how long it took sea creatures to consume those lost in the Titanic because searchers got there so many years later.

Glad to see they found it
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Old 4th Apr 2011, 20:27
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Bodies found in wreckage

France says finds bodies in Atlantic crash wreckage - Yahoo! News

D. Fisher
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Old 4th Apr 2011, 20:31
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The CNN piece today said the oxygen masks were not imployed in the recovered wreckage and that implies the airfame was intact (pressurized) at the time of the ocean impact.
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Old 4th Apr 2011, 20:45
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robertbartsch;

intact yes, pressurized no. The negative pressure relief valve equalized cabin pressure shortly before impact.

regards,
HN39
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Old 4th Apr 2011, 20:50
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Is it just me, or does it look like the engine in the picture had not been turning at the moment of impact. If it had, you would expect fractured or bent blades all around, not just on one side, wouldn't you? Could suggest they suffered a flame out.

The missing blades presumably would have been around 6 o'clock position and were ripped away on impact, but since the engine wasn't turning, the blades that were closer to the 12 o'clock position were preserved. Sound plausible? Or am I thinking too much of props?
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Old 4th Apr 2011, 20:51
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wreckage location

Won't the location of the debris become very obvious once the recovery vessels turn up ? Before then, what is the risk beyond a boat load of photographers ?
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Old 4th Apr 2011, 21:04
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Mr. Optimistic, it may be that France and/or Brazil need to establish a maritime security zone. and are working on the boundaries and procedures for doing so. If such a security zone is established, the national government(s) would be able to keep unwanted vessels and aircraft away.
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Old 4th Apr 2011, 21:11
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Do you really want a load of paparazi taking photos of an open hold with bodies inside it or the potential of a body being able to be seen via a window ?

After all, they would publish it if they got the photo.

I would like to see a Maritime exclusion zone around it.

.
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Old 4th Apr 2011, 21:11
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Though the BEA have chosen to keep the exact location of the debris field secret, my best estimate would be that its about 335°T x 6.5NM from LKP. This is based solely on where I suspect the "Alucia" was working, i.e. she had completed the keyhole section in the rugged terrain to the NW and was working in an unfinished section to the south. I could also be totally wrong.



Yellow circle radii are multiples of 10NM from Last Known Position.
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Old 4th Apr 2011, 21:23
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Added another overlay of debris recovery locations.

I wonder what items 9 and 11 are...

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Old 4th Apr 2011, 21:43
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Though I remember questioning the relevance of an item of debris located close to where the debris field is believed to be, I consequently dismissed the recorded location as being a transcription error where a handwritten 3,66 was later transcribed as 3,11 (3.66/3.11). I am starting to think that maybe that assumption was wrong, and the debris in question had made its way back to the surface.

Post #911 clearly shows the location and date of recovery of that debris item.
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Old 4th Apr 2011, 21:55
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Is it just me, or does it look like the engine in the picture had not been turning at the moment of impact. If it had, you would expect fractured or bent blades all around, not just on one side, wouldn't you? Could suggest they suffered a flame out.
I don't see any blades visible, non-rotating struts yes.

Of course the pics are4 quite low in resolution so far.

Occams razor suggests the most likely scenario is the engines were on the bottom of the wing when it hit flat shearing away all the soft structure around the engines (Large diameter cases and nacelle0, but leaving intermediate case behind the fan mostly intact.

Let's wait and see if any better photos show up.
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Old 4th Apr 2011, 22:00
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Debris size & speed

After a high speed impact, the SR-111 MD11 disintegrated into 2 million (recovered) pieces*. CNN reported the biggest one was the size of a car door. The average length of the 160 miles of wire recovered was 3 ft. The large size of the debris spotted today clearly points to a very much lower speed at impact.

*Swissair 111 Crash Report Delayed
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