AF 447 Search to resume
PRIM 1 and SEC 1 Faults
Quote from Svarin (Apr12/1754z, currently #3387 on Page 170):
"02:13:45 F/CTL PRIM1 FAULT
02:13:51 F/CTL SEC1 FAULT
First, this describes a simultaneous failure of PRIM1 and SEC1, which greatly reduces the likelyhood of a manual shutdown or reset."
Your analyses in the area of possible wiring fault and possible pitch-up have been most thought-provoking. Thanks.
However, I'm not entirely convinced the two faults were necessarily (a) simultaneous and (b) "permanent" (for want of a better word).
Re my (a), I agree that SEC1 is probably below PRIM 1 in CMC transmission priority, so they might have been simultaneous. But could there not equally be a gap of up to (say) 11 seconds?
Re my (b), these are cockpit (ECAM) warnings that have sufficient maintenance implication to justify an ACARS message. The BEA comments, in both cases: "this shutdown could be the result of a command or of a failure."
Am wondering if the crew might have gone for a quick trip-and-reset (re-boot) on PRIM 1, followed almost immediately (not simultaneously) by the same action on SEC 1. (We used sometimes to resort to similar expedients in the early days on the A320. Don't know what current thinking on the A330 is, let alone SOPs – but they would have been out of the window by 0213z.)
If a computer had not displayed a FAULT W/L (warning light) prior to a crew-selected re-boot, the fault W/L and associated ECAM message might last for just a few seconds. The question is, would it subsequently be transmitted by ACARS? The other, remote possibility is that the crew might have left one or both PBs (push-buttons) in the OFF position, deliberately or otherwise.
CONF iture,
I agree with your above point that speed reduction to turbulence speed might have been in progress at 0210z, implying low N1. Just a reminder that the CF6 engine does not use EPR, N1 being the primary indication of thrust.
Chris
"02:13:45 F/CTL PRIM1 FAULT
02:13:51 F/CTL SEC1 FAULT
First, this describes a simultaneous failure of PRIM1 and SEC1, which greatly reduces the likelyhood of a manual shutdown or reset."
Your analyses in the area of possible wiring fault and possible pitch-up have been most thought-provoking. Thanks.
However, I'm not entirely convinced the two faults were necessarily (a) simultaneous and (b) "permanent" (for want of a better word).
Re my (a), I agree that SEC1 is probably below PRIM 1 in CMC transmission priority, so they might have been simultaneous. But could there not equally be a gap of up to (say) 11 seconds?
Re my (b), these are cockpit (ECAM) warnings that have sufficient maintenance implication to justify an ACARS message. The BEA comments, in both cases: "this shutdown could be the result of a command or of a failure."
Am wondering if the crew might have gone for a quick trip-and-reset (re-boot) on PRIM 1, followed almost immediately (not simultaneously) by the same action on SEC 1. (We used sometimes to resort to similar expedients in the early days on the A320. Don't know what current thinking on the A330 is, let alone SOPs – but they would have been out of the window by 0213z.)
If a computer had not displayed a FAULT W/L (warning light) prior to a crew-selected re-boot, the fault W/L and associated ECAM message might last for just a few seconds. The question is, would it subsequently be transmitted by ACARS? The other, remote possibility is that the crew might have left one or both PBs (push-buttons) in the OFF position, deliberately or otherwise.
CONF iture,
I agree with your above point that speed reduction to turbulence speed might have been in progress at 0210z, implying low N1. Just a reminder that the CF6 engine does not use EPR, N1 being the primary indication of thrust.
Chris
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Originally Posted by Chris Scott
Am wondering if the crew might have gone for a quick trip-and-reset (re-boot) on PRIM 1, followed almost immediately (not simultaneously) by the same action on SEC 1. (We used sometimes to resort to similar expedients in the early days on the A320. Don't know what current thinking on the A330 is, let alone SOPs – but they would have been out of the window by 0213z.)
From my experience on the 330, I have never had or thought to reset such computer unless specifically requested by ECAM or QRH.
I take note for the CF6. Thanks.
CONF iture;
Yes, fully agree - it is a serious matter that requires some careful thought and action.
Selecting the turbulence penetration speed on the FCU would not reduce the N1 into a low range.
The cruise N1 for M0.82 would be around 86%. The turbulence penetration speed at FL350 is 260kts, (M0.78 @ FL370) and the power setting is 76%.
Setting 260kts in the FCU speed window may initially reduce the N1 below the 76% and as the speed was achieved would return to the target setting but any reduction would not be in a 'low range', nor would a disconnection (caused by system problems) leave the aircraft at risk.
Sometimes in mountain wave conditions where the speed is increasing, the A/T will reduce the N1, sometimes even to idle if the Mach is getting close to VMO/MMO but for a twenty to twenty-five knot reduction the N1 would not reduce into what could be called "low range". Even if it actually did, it takes a long time to lose enough speed to be at risk.
The thrust lock function is easily handled using manual thrust, (move the levers to set 76%). The severe turbulence penetration drill states that the A/T should be disconnected if speed variations are large.
I have never had or thought to reset such computer unless specifically requested by ECAM or QRH.
If at the time of the automatic disconnection of the autothrust with activation of the thrust lock function, the A/THR had lowered the EPR to reduce the speed to the selected mach for turbulence, it is possible that the N1 were in a lower range than usual for cruise
The cruise N1 for M0.82 would be around 86%. The turbulence penetration speed at FL350 is 260kts, (M0.78 @ FL370) and the power setting is 76%.
Setting 260kts in the FCU speed window may initially reduce the N1 below the 76% and as the speed was achieved would return to the target setting but any reduction would not be in a 'low range', nor would a disconnection (caused by system problems) leave the aircraft at risk.
Sometimes in mountain wave conditions where the speed is increasing, the A/T will reduce the N1, sometimes even to idle if the Mach is getting close to VMO/MMO but for a twenty to twenty-five knot reduction the N1 would not reduce into what could be called "low range". Even if it actually did, it takes a long time to lose enough speed to be at risk.
The thrust lock function is easily handled using manual thrust, (move the levers to set 76%). The severe turbulence penetration drill states that the A/T should be disconnected if speed variations are large.
Just a quick question. (Apols if already been posted)
Is there any way the reverse thrusters could have been deployed with all the apparent failings going on the flight deck, or is this outcome totally impossible due to fail safes. (if so, would you get a record of this in ACARS?)
Thanks.
Is there any way the reverse thrusters could have been deployed with all the apparent failings going on the flight deck, or is this outcome totally impossible due to fail safes. (if so, would you get a record of this in ACARS?)
Thanks.
CONF iture and PJ2,
Thanks for the information on the SOPs and practcalities of FCC resets. As I said:
"but they [SOPs] would have been out of the window by 0213z"
Perhaps I should have said "might". Aside from SOPs, sad to say, there was little time left for "careful thought and action".
It is a tantalising, if understandable, feature of these WRN ("cockpit effect messages") from ACARS that their duration seems to be indeterminate.
Thanks for the information on the SOPs and practcalities of FCC resets. As I said:
"but they [SOPs] would have been out of the window by 0213z"
Perhaps I should have said "might". Aside from SOPs, sad to say, there was little time left for "careful thought and action".
It is a tantalising, if understandable, feature of these WRN ("cockpit effect messages") from ACARS that their duration seems to be indeterminate.
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Is there any way the reverse thrusters could have been deployed with all the apparent failings going on the flight deck, or is this outcome totally impossible due to fail safes.
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Originally Posted by PJ2
Sometimes in mountain wave conditions where the speed is increasing, the A/T will reduce the N1, sometimes even to idle if the Mach is getting close to VMO/MMO but for a twenty to twenty-five knot reduction the N1 would not reduce into what could be called "low range". Even if it actually did, it takes a long time to lose enough speed to be at risk.
Note that the turbulence penetration speed for the 332 is M0.80 @ FL370 compared to M0.78 for the 333 I believe.
Chris, CONF iture;
Agree that things unfolded quickly and that time to consider and act was short. I think we're bumping up against the limitations of text and typing...we've flown the Airbus so I think we're meaning and understanding in the same way. In my post I just wanted to clarify that the N1s would not be in a low range regime as a result of selecting a turbulence speed even if the a/t disconnected right at that point. I'm assuming here that the idea behind the low N1 range was, the aircraft would lose speed and stall given that it was in Alt2 law, etc? ...if not, then I haven't, (not for the first time!), understood.
The notion behind WRG as I understood it from some reading and research was that it was not necessarily a physical "wiring" matter, but was a term used to describe a situation where the two FWCs could not independently interrogate the computers sending the original fault message(s) such that the "correlation" stage of fault determination could complete. The reason (again making great assumptions and interpretations here as I am not an engineer), that perhaps the timings of the message was not long enough for the process to complete.
Again, bearing in mind that the purpose of the [Computer fault] > FWS/FWC> CMC > ACARS process, (aside from warning the crew, etc), is to provide maintenance with sufficient information to understand the fault well enough to prepare for handling it at arrival, (ostensibly to avoid delays, or expensive repairs which don't fix the problem, etc).
As we're keenly aware, we're using the ACARS data in the same way investigators would use flight recorder information but with 26 text messages instead of 1800 or so aircraft and flight parameters and the voice/sound recordings. We're looking at minute entrails to see what produced the particular combination of messages in (roughly) the timings seen. The limitations are severe even with the photographs but I'll be surprised if, throughout the thread, some haven't come very close to what happened.
CONF iture, thanks for keeping me honest! Are you on the A330 now?
Agree that things unfolded quickly and that time to consider and act was short. I think we're bumping up against the limitations of text and typing...we've flown the Airbus so I think we're meaning and understanding in the same way. In my post I just wanted to clarify that the N1s would not be in a low range regime as a result of selecting a turbulence speed even if the a/t disconnected right at that point. I'm assuming here that the idea behind the low N1 range was, the aircraft would lose speed and stall given that it was in Alt2 law, etc? ...if not, then I haven't, (not for the first time!), understood.
The notion behind WRG as I understood it from some reading and research was that it was not necessarily a physical "wiring" matter, but was a term used to describe a situation where the two FWCs could not independently interrogate the computers sending the original fault message(s) such that the "correlation" stage of fault determination could complete. The reason (again making great assumptions and interpretations here as I am not an engineer), that perhaps the timings of the message was not long enough for the process to complete.
Again, bearing in mind that the purpose of the [Computer fault] > FWS/FWC> CMC > ACARS process, (aside from warning the crew, etc), is to provide maintenance with sufficient information to understand the fault well enough to prepare for handling it at arrival, (ostensibly to avoid delays, or expensive repairs which don't fix the problem, etc).
As we're keenly aware, we're using the ACARS data in the same way investigators would use flight recorder information but with 26 text messages instead of 1800 or so aircraft and flight parameters and the voice/sound recordings. We're looking at minute entrails to see what produced the particular combination of messages in (roughly) the timings seen. The limitations are severe even with the photographs but I'll be surprised if, throughout the thread, some haven't come very close to what happened.
CONF iture, thanks for keeping me honest! Are you on the A330 now?
Last edited by PJ2; 14th Apr 2011 at 16:57.
HazleNuts
I was not aware of there being a cyclic nature to the high speed buffet. The only times I have experienced the high speed buffet on all three types I did not experience that but, in general, feel that it was less 'rough' and of a higher frequency than the low speed buffet. But it was all a long time ago and memory plays tricks.
Obviouslty, too, my experience was on older aircraft not FBW, and neither do I know what stall training is done these days. However, if it is only to the onset of buffet or stall warning, pilots will not know the stall characteristics of their aircraft. Also, if it is done using the traditional method of trimming to 1.3Vs and then reducing airspeed at 1kt/sec they will be unaware of two important factors:-
(1) In an unintentional stall following an unnoticed decay of airspeed (Turkish Airlines at Amsterdam is a case in point) the autopilot will have trimmed the stabiliser nose up. Therefore, when the pilot belatedly recognises the situation, the aircraft will be severely out of trim with, perhaps, insufficient elevator authority to accomplsh a straight forward recovery, and this will be excerbated with underslung wing mounted engines when power is applied.
(2) In the case of an accelerated stall caused, either by pulling G or by a large gust or both, the time between the onset of buffet and the stall itself may be very short, only 1 or 2 seconds - insufficient time for most pilots to recognise the problem.
Of course, if what others have said about the Airbus aircraft shouting 'stall' 'stall' 'stall', stall recognition should be obvious! However, when you have lost envelope protection (and here again I do not know enough about FBW), and with modern wings designed for max efficiency in cruise is there a tendancy in some conditions for the aircraft to continue pitching nose up? If there is, and AF447 was in alternate law, it might be possible to get into a super stall very quickly.
I won't add more to the already extensive speculations in this thread, as other have said let's wait for the recorders. But I do wonder whether enough training is done on all aspects of the stall rather than just demonstrating the approach to and recovery from the classic stall.
I was not aware of there being a cyclic nature to the high speed buffet. The only times I have experienced the high speed buffet on all three types I did not experience that but, in general, feel that it was less 'rough' and of a higher frequency than the low speed buffet. But it was all a long time ago and memory plays tricks.
Obviouslty, too, my experience was on older aircraft not FBW, and neither do I know what stall training is done these days. However, if it is only to the onset of buffet or stall warning, pilots will not know the stall characteristics of their aircraft. Also, if it is done using the traditional method of trimming to 1.3Vs and then reducing airspeed at 1kt/sec they will be unaware of two important factors:-
(1) In an unintentional stall following an unnoticed decay of airspeed (Turkish Airlines at Amsterdam is a case in point) the autopilot will have trimmed the stabiliser nose up. Therefore, when the pilot belatedly recognises the situation, the aircraft will be severely out of trim with, perhaps, insufficient elevator authority to accomplsh a straight forward recovery, and this will be excerbated with underslung wing mounted engines when power is applied.
(2) In the case of an accelerated stall caused, either by pulling G or by a large gust or both, the time between the onset of buffet and the stall itself may be very short, only 1 or 2 seconds - insufficient time for most pilots to recognise the problem.
Of course, if what others have said about the Airbus aircraft shouting 'stall' 'stall' 'stall', stall recognition should be obvious! However, when you have lost envelope protection (and here again I do not know enough about FBW), and with modern wings designed for max efficiency in cruise is there a tendancy in some conditions for the aircraft to continue pitching nose up? If there is, and AF447 was in alternate law, it might be possible to get into a super stall very quickly.
I won't add more to the already extensive speculations in this thread, as other have said let's wait for the recorders. But I do wonder whether enough training is done on all aspects of the stall rather than just demonstrating the approach to and recovery from the classic stall.
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Hi,
Is it possible the "vertical compression forces from bottom" seen by BEA (and supposed due to deceleration (~100g) with a/c quite horizontal) originates, from water pressure, with a/c going meters underwater (nose down descent all the way)? (argument: engines "peeled off").
Would be "Dozens of bodies are present among the wreckage." ( Le Figaro - France : Le repchage des corps des victimes en question ) preventing BEA for showing pictures of the tail?
Sorry for my very rude English,
Is it possible the "vertical compression forces from bottom" seen by BEA (and supposed due to deceleration (~100g) with a/c quite horizontal) originates, from water pressure, with a/c going meters underwater (nose down descent all the way)? (argument: engines "peeled off").
Would be "Dozens of bodies are present among the wreckage." ( Le Figaro - France : Le repchage des corps des victimes en question ) preventing BEA for showing pictures of the tail?
Sorry for my very rude English,
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The point I was trying to make (or be corrected on) is does it seem plausible that the a/c went from A to B without the need to deviate off course to make the sums work. Since the opinion seems to be that the engines were producing thrust, that the a/c remained structurally intact and that a turning manoeuvre would be avoided in the circumstances, was hoping to establish that such was possible without 'hand of God' stuff.
and it results in a relativ stable decending speed, depending on wing area/profile/wight/place of CG/etc so it must not need the steering of the hand of god to fall from 10000m within a few km to nearly every place into the water
look at the polar diagram of mr.lilienthal
The aerodynamics of Lilienthal
so who know which AOA result in which decending speed, and which place of CG (or which elevator pitch) make this way down then stable....
grity
Speaking of AoA, I finally found something I think was raised in previous discussions (search did me no good in finding the thread)
That's a lot of if, however as this bulletin was issued in 2010, it may be that the AF 447 mishap was related to discovering discrepancies.
And it may also be unrelated. I note that it would take multiple failures, and multiple probes well past manufacture date, and in service, having this problem all at once for it to have influenced AF 447.
7 July 2010 (e) The mandatory continuing airworthiness information (MCAI) states:
Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA-2010-0675; Directorate Identifier 2010-NM-061-AD] RIN 2120-AA64
During Airbus Final Assembly Line reception flight tests, AoA data from two different aeroplanes were found inaccurate. Inaccuracy was confirmed by flight data analysis.
Investigation conducted by Thales on the removed probes revealed oil residue between the stator and the rotor parts of the AoA vane position resolvers. This oil residue was due to incorrect cleaning of the machining oil during the manufacturing process of the AoA resolvers. At low temperatures, this oil residue becomes viscous (typically in cruise) causing lag of AoA vane movement.
Such condition could lead to discrepant AoA measurement. If not corrected, and if two or three AoA probes were simultaneously affected and provided wrong indications of the AoA to a similar extent, it could lead to a late activation of the angle of attack protection, which in combination with flight at high angle of attack would constitute an unsafe condition.
Therefore, this [European Aviation Safety Agency (EASA)] AD requires a one time inspection of the Thales Avionics AoA probe P/N C16291AA in order to identify the suspect parts and to remove them from service.
Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA-2010-0675; Directorate Identifier 2010-NM-061-AD] RIN 2120-AA64
During Airbus Final Assembly Line reception flight tests, AoA data from two different aeroplanes were found inaccurate. Inaccuracy was confirmed by flight data analysis.
Investigation conducted by Thales on the removed probes revealed oil residue between the stator and the rotor parts of the AoA vane position resolvers. This oil residue was due to incorrect cleaning of the machining oil during the manufacturing process of the AoA resolvers. At low temperatures, this oil residue becomes viscous (typically in cruise) causing lag of AoA vane movement.
Such condition could lead to discrepant AoA measurement. If not corrected, and if two or three AoA probes were simultaneously affected and provided wrong indications of the AoA to a similar extent, it could lead to a late activation of the angle of attack protection, which in combination with flight at high angle of attack would constitute an unsafe condition.
Therefore, this [European Aviation Safety Agency (EASA)] AD requires a one time inspection of the Thales Avionics AoA probe P/N C16291AA in order to identify the suspect parts and to remove them from service.
And it may also be unrelated. I note that it would take multiple failures, and multiple probes well past manufacture date, and in service, having this problem all at once for it to have influenced AF 447.
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Back at post #3478 , swordfish41 made reference to the sidescan sonar nadir/shadow made by a large piece of wreckage to the east of the debris field. An enlarged sidescan sonar image of the debris field published by the BEA is reproduced below.
I looked at the sidescan image a couple of days ago and enlarged it to discover the curved shadow, and suspect that it is the forward fuselage. The length would seem correct, but the skin may have been split away from the frames to present an enlarged width. I have good reason to suspect that swordfish41's analysis is reliable, as he was responsible for the finding of the HMS "Ark Royal", that sank in the Mediterranean in 1941, by using 200kHz sidescan sonar for a BBC documentary. I posted some information on the finding of the Ark Royal in post #1038. A post in response by swordfish41 is at post #1049.
With regard to the AF447 wreckage, the forward fuselage probably parted company with the rest at impact, and with less impediment to its forward movement, made its way to the bottom on a slightly different trajectory than other debris. If this is the case, then the heading at impact was around 070°T.
EDIT :: True north is 10° to the top right of the Y axis in the above graphic.
grity; BJ-ENG;
The impact graphics at post #2066, seem to match the injuries resulting from a 100g+/- impact as researched by BJ-ENG. Also, grity's analysis of the likey 'g' forces tends to match what I had proposed, and the small debris field found would tend to support that. Thanks guys.
I looked at the sidescan image a couple of days ago and enlarged it to discover the curved shadow, and suspect that it is the forward fuselage. The length would seem correct, but the skin may have been split away from the frames to present an enlarged width. I have good reason to suspect that swordfish41's analysis is reliable, as he was responsible for the finding of the HMS "Ark Royal", that sank in the Mediterranean in 1941, by using 200kHz sidescan sonar for a BBC documentary. I posted some information on the finding of the Ark Royal in post #1038. A post in response by swordfish41 is at post #1049.
With regard to the AF447 wreckage, the forward fuselage probably parted company with the rest at impact, and with less impediment to its forward movement, made its way to the bottom on a slightly different trajectory than other debris. If this is the case, then the heading at impact was around 070°T.
EDIT :: True north is 10° to the top right of the Y axis in the above graphic.
grity; BJ-ENG;
The impact graphics at post #2066, seem to match the injuries resulting from a 100g+/- impact as researched by BJ-ENG. Also, grity's analysis of the likey 'g' forces tends to match what I had proposed, and the small debris field found would tend to support that. Thanks guys.
Last edited by mm43; 14th Apr 2011 at 22:29.
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Originally Posted by Shadoko
Is it possible the "vertical compression forces from bottom" seen by BEA (and supposed due to deceleration (~100g) with a/c quite horizontal) originates, from water pressure, with a/c going meters underwater (nose down descent all the way)? (argument: engines "peeled off").
Would be "Dozens of bodies are present among the wreckage." ( Le Figaro - France : Le repchage des corps des victimes en question ) preventing BEA for showing pictures of the tail?
Sorry for my very rude English,
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mm43
Thanks for the enlargement. I had looked at this photo (not enlarged) and wondered if it (the little separate blip) might be what is left of the tail section. There is a fair amount of mass back there and it may have settled on a different trajectory as you pointed out. I say this as there has been no mention of the forward fuselage, but speculation (confirmed or not) of finding the tail section. Obviously, there are no doubt additional photos of the wreckage, which have not been released for various reasons, but exist in the hand of the investigating authorities and they know what this sidescan image represents. I suppose we will know soon.
Thanks for the enlargement. I had looked at this photo (not enlarged) and wondered if it (the little separate blip) might be what is left of the tail section. There is a fair amount of mass back there and it may have settled on a different trajectory as you pointed out. I say this as there has been no mention of the forward fuselage, but speculation (confirmed or not) of finding the tail section. Obviously, there are no doubt additional photos of the wreckage, which have not been released for various reasons, but exist in the hand of the investigating authorities and they know what this sidescan image represents. I suppose we will know soon.
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Yes Grity thanks, good way of looking at it. We'll assume up to circa 100g, anywhere form 60 to 100 ++ seems the ball park actually. Certainly fits with some of the post mortem findings .
@Lonewolf and HarryMann
if you stopp a falling pelvis with a vertical speed of 15000 ft/min (15000*0,3/60 =75 m/sec) with a constant force of 100 g-load`s (100g=981m/sec˛) it stopps to zerro after 75/981= 0,076 sec and a way of less than 3m !
water is nearly incompressible at this speed, (within 0,07 sec it can not move much to the side), it makes not realy a great difference if you crash into concrete or water with 75m/sec !
and this very short stopway is plausible:
ca. 3m will be the sum of the compressible space between the pelvis and the water, (the space under the seat, the airspace into the baggage compartment, and the construction space in the lower fuselage.....)
grity
if you stopp a falling pelvis with a vertical speed of 15000 ft/min (15000*0,3/60 =75 m/sec) with a constant force of 100 g-load`s (100g=981m/sec˛) it stopps to zerro after 75/981= 0,076 sec and a way of less than 3m !
water is nearly incompressible at this speed, (within 0,07 sec it can not move much to the side), it makes not realy a great difference if you crash into concrete or water with 75m/sec !
and this very short stopway is plausible:
ca. 3m will be the sum of the compressible space between the pelvis and the water, (the space under the seat, the airspace into the baggage compartment, and the construction space in the lower fuselage.....)
grity
mm43 and swordfish41,
Is there a possibility that Turbine D is right, and that it is the tail section (by which I think he is referring to the aft fuselage)?
Would the debris field alignment (approximately 070/250) necessarily be roughly indicative of the heading at sea-level impact, despite currents on the way down? If the curved piece in the north-east was the aft fuselage, would that suggest the Hdg 250 rather than the 070?
swordfish41,
Do you think the engines may be present in this pictured debris field? Could the laterally-lying pieces extending northwards include a wing box?
Is there a possibility that Turbine D is right, and that it is the tail section (by which I think he is referring to the aft fuselage)?
Would the debris field alignment (approximately 070/250) necessarily be roughly indicative of the heading at sea-level impact, despite currents on the way down? If the curved piece in the north-east was the aft fuselage, would that suggest the Hdg 250 rather than the 070?
swordfish41,
Do you think the engines may be present in this pictured debris field? Could the laterally-lying pieces extending northwards include a wing box?
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Originally posted by Chris Scott ...
Is there a possibility that Turbine D is right, and that it is the tail section (by which I think he is referring to the aft fuselage)?
Is there a possibility that Turbine D is right, and that it is the tail section (by which I think he is referring to the aft fuselage)?
My interpretation of the BEA's press release, was that what was shown on the scan was the extent of the debris field. I believe everything that went to the bottom is represented there.
