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Old 14th June 2009, 00:35   #1401 (permalink)
 
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strange-display

Strange display, that shows you 2 different ranges in TCAS. must be confusing.
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Old 14th June 2009, 00:44   #1402 (permalink)
 
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I cant translate hispanic -Rugged...??

Following comments off the cuff and all deletable
Todays report of rugged item picked up by freighter 400 km away
Photo seems to show a crewmans foot to give scale
Item about 1 metre x 3 metre
Cross section is tapered like an aerofoil,
But surfaces look planar with a slight "hard chine bend"
Could be a door , some sort of control surface , flap , or an internal
longitudinal structure.
It looks (by coincidence of dark background of ship structure) as if
the panel is translucent
400 km a long way away
Reports exist of several fatal European CB encounters by paragliders,and hang gliders finishing, up to around 100 miles from where they entered cloud Frozen solid and asphyxiated.Could light broken parts of aircraft expect to be scattered by CB in the same way
I was informed one time of giant hail/ very large lumps of ice falling from a storm in South Africa required a calculated 300mph updraft to support them during build up accretion
Chillyflier
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Old 14th June 2009, 00:49   #1403 (permalink)
PJ2
 
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Harry - not sure where my post went - I may have deleted it when adding the photos, now found below, of the spoiler panel.

I offered my thoughts on what the recovered parts on display were, which is new information - the most interesting parts I think are the two, intact overhead bin covers and the doctor's kit.

We cannot say anything from the photos about the F/A seatbelts. It's not from L1 where the CIDS is as there are no traces of any such displays or equipment on the bulkhead in question. It could be from any section - we just can't say.

"wilyflier";

It's a spoiler panel from one of the wings.

The torn section in the center is where the hydraulic cylinder that extends the spoiler is attached. The attachment points to the rear spar wing structure can be seen at either end.







Last edited by PJ2 : 14th June 2009 at 02:20.
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Old 14th June 2009, 01:03   #1404 (permalink)
 
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long way

Thanks PJ2

How does that 415km northwest of st peter and st paul relate to fin and rudder recovery position??
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Old 14th June 2009, 01:34   #1405 (permalink)
 
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LH turbulence, two days prior

FWIW

Quote:
...At the Lufthansa flight 507 from Sao Paulo to Frankfurt everything seemed to run as planned. The flight was quiet, the stewardesses served the passengers, all was peaceful. Three hours after the start of this suddenly changed, because the jumbo in the midst of a severe tropical storm was advised.

The relaxed atmosphere on board was easy after the first shock apparently soon to panic. After 15 minutes, fought during the 350-ton jumbo with so great turbulence and air holes that passengers are not restrained to the floor and the ceiling were hurled.

A man had his head pushed so hard that he bled heavily. His wound had to be later by a doctor on board are sewn says "star".

Even beverage carts and luggage herumgeschleudert should have been.

"This is something I have on this route has never experienced. We had to claw regelrecht firmly, "the magazine quoted a passenger. Once the worst was over, that chaos prevailed in the cabin: people crying, leftover food and clothes, "everything just a single mash," said another passenger as "star".

How had it come? The pilot was apparently from the strong storms have been surprising. He was in the dark night, the tropical storm cells do not recognize them. Apparently the weather had no radar warning.

Lufthansa: turmoil not only on this route

"Stern" had spoken with passengers, with the horror of it had come, and the horror of the flight case made public today. Lufthansa again mentioned the incident until today - despite only two days later occurring crash disaster AF447 on the same route.

At Horror flight approached, a spokesman relativised Lufthansa Blick.ch from the incident. It had said the turbulence in flight and given a slightly injured. By "flying drinks trolley 'could, however, no question.

The air eddies were flying "of everyday life," said the spokesman continued. And: "Such turbulence is also not just about this area, but on quite a number of routes around the world."

The fact that the weather radar shows the storm does not have denied the Lufthansa spokesman also. "The radar worked and the storm was very well displayed. But that the turbulence in the storm would be so severe, it can also be a radar does not show. "
(gux)...
from: Das Blick, 6 June 2009 (google translation)
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Old 14th June 2009, 01:36   #1406 (permalink)
 
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PJ2 wrote: "the most interesting parts I think are the two, intact overhead bin covers and the doctor's kit."

I agree with PJ2. These are examples (IMO) of items that investigators can look at and, surprisingly quickly, eliminate a couple of scenarios (re aircraft breakup). I would add that eliminating some possibilities DOES NOT infer being (lineally) any closer to "causes". It's simply how investigations proceed.

Grizz
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Old 14th June 2009, 01:45   #1407 (permalink)
 
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It almost appears as the spoiler had been fully deployed when it was torn away. When stowed, it's a fairly firmly rooted panel, and flush to the airflow across the wing. I'm trying to visualize the type of odd flow that would pull it out of the wing while stowed. Looking at the hinged corner failures, it would appear the spoiler failed forward, away from its mount, with the airflow from the trailing edge of the wing flowing forward.
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Old 14th June 2009, 01:46   #1408 (permalink)
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Quote:
It's simply how investigations proceed.
Precisely.

Tell-tale marks, including the texture, color of such traces, and the order in which they occurred, are as important as fracture patterns themselves. There'll be a way for AB to determine which spoiler this was and possibly which wing.
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Old 14th June 2009, 01:51   #1409 (permalink)
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Will;

Re possible air "flow" over the wing... or what other possibly-mechanical force? The attach points are intact, with some small structure attached to one end - cylinder still likely attached to the spar.

Last edited by PJ2 : 14th June 2009 at 02:14.
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Old 14th June 2009, 01:55   #1410 (permalink)
 
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PJ2, yes, but the surface skin is not broken, while the underside has a fracture that would suggest forward failure, and the rollers ripped from the rails/attach points. Deployed in normal fashion, airflow pushes energetically to stow the spoiler, the structure is not designed to prevent the spoiler from 'being pulled or forced' forward. It is only a suggestion, but may explain why the fracture is underneath and the attachments are fairly sound.
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Old 14th June 2009, 01:59   #1411 (permalink)
 
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Quote:
It almost appears as the spoiler had been fully deployed when it was torn away. When stowed, it's a fairly firmly rooted panel, and flush to the airflow across the wing. I'm trying to visualize the type of odd flow that would pull it out of the wing while stowed.
For constant flap setting, a wing changes load mostly on the forward part with angle of attack. The load on the aft part of the wing where the spoiler is changes very little with lift/AOA, though q increases with speed.

Can't tell if it separated in flight.
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Old 14th June 2009, 02:02   #1412 (permalink)
 
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I'll be blunt. It appears that if airborne prior to failure, the wing was traveling through the airstream backward.
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Old 14th June 2009, 02:04   #1413 (permalink)
 
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Will, can see your point now. If they were deployed, and the airplane broke up in fight, then the air would have been coming from behind during the tumble. That could indicate that in forward flight, q wasn't high enough to fail them aft.
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Old 14th June 2009, 02:06   #1414 (permalink)
 
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Quote:
Originally Posted by Will Fraser View Post
I'll be blunt. It appears that if airborne prior to failure, the wing was traveling through the airstream backward.
I'm not sure evidence supports that as an only conclusion.

Without suggesting that this is in any way validated by the picture, IF an aircraft were to (for whatever reason) exceed its demonstrated dive speed and be subject as a result to aeroelastic instability (flutter) of the wing I can imagine all kinds of unusual and extreme loads being applied to parts of the wings. Only someone who knows exactly what damage that part has and also what it would be subject to under various scenarios can identify the most likely cause.
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Old 14th June 2009, 02:13   #1415 (permalink)
 
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Mad. Of course. I have no conclusions about anything. I certainly don't speak the language of the events during the a/c demise. It is simply what that unfortunate assembly could be implying. Will catch up later. It is reasonably consistent with a possibility the a/c tumbled. They will do that without much tail. Swap ends.

Will
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Old 14th June 2009, 02:21   #1416 (permalink)
 
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Will I would tend to agree. Had the actuator pushed the spoiler up into the airflow (travelling in the designed direction) but above the designed deployment structural speed, there would likely be convex deformation on the upper surface above the actuator attach point, and failure signatures on the hinge attach points.

There are not too many circumstances that would have a wing facing aft into airflow strong enough to do that. That is not to discount the possibility of this having happened as a result of the wing impacting the water trailing edge first.
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Old 14th June 2009, 02:27   #1417 (permalink)
 
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pathologists will play a vital part as in British Comet disasters

I never knew just how valuable pathology reports really where in relation to air accident investigations . amazing to think that even when wreckage is very sparse and in some caese never found .

The Contribution a Pathologist could make was dramatically demonstrated during the investigation of British Comet disasters over Mediterranean in 1954. As the wreckage of aircraft was not available, investigating doctors inferred from the autopsies and other simulating experiments, that occupants suffered a violent upward and forward motion and deduced that injuries could be due to explosive decompression. They also showed experimentally the mechanism of injuries due to impact on sea.
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Old 14th June 2009, 02:33   #1418 (permalink)
 
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Spoiler

Is it a possibility that the spoiler come off through hydraulic water pressure underneath it when the wing or part of it hit the water?
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Old 14th June 2009, 02:38   #1419 (permalink)
 
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Seems like something as simple as a cartwheel on impact with the water could explain one wing entering backwards.

Last edited by Chu Chu : 14th June 2009 at 02:59.
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Old 14th June 2009, 02:56   #1420 (permalink)
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I have been looking at the last few posts about the spoiler.

I have never commented on any of the crash threads over the years until now although like many I read daily.

The lesson for me in examining all of the hypotheses put up by very well meaning and knowledgeable contributors is that there will always been a host of reasonable explanations until detailed (and microscopic even) tests are conducted in a laboratory.
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