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AF447

Old 17th Jun 2009, 21:00
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"Shrapnel Damage"

lomapaseo, PJ2,

I find your "shrapnel" comments interesting, I had the same thought when I first studied photos of the VS.

Take a look at this shot: http://www.fab.mil.br/portal/voo447/...609/foto_3.jpg

I can see 3 "cuts" in the leading edge of the VS, anyone else concur?
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Old 17th Jun 2009, 21:15
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LIS -
1) Descending to warm air would mean a huge fuel penalty. They only have enough fuel to reach their destination at cruising altitudes. Descending even for a short time would mean they would not have enough fuel to complete the flight.
This is the purpose of both discretionary extra fuel and Dakar.
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Old 17th Jun 2009, 21:16
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ISIS, stby altitude, altitude indications

As written (by me among others) in previous posts, the ISIS is a self contained instrument providing Airspeed from stby pitot, attitude from internal gyros, Altitude from STBY static ports, and slip/skid info from accelerometers,

ISIS IS the stby instuments !

direct inputs from the pitot and from the static ports are provided. No computer inbetween !!

Also, the FMGC provides a "backup altitude" which is provided from the GPSs on the DATA / GPS page. It's not a pressure altitude, but nevertheless gives a good idea of whether you are at 35000' or 2000' !!

The QRH checklist for "Unreliable airspeed" suggests to use this it by the way.

please read the important info provided on the thread so IT is not clogged with redundant, already asked and answered questions !
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Old 17th Jun 2009, 21:24
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I'm wondering, Poison's message aside, has anybody fed the sequence of
ACARS into a simulator to see what the result is? Either in reverse order of received, or in order listed on the ACARS message. Does one message trigger the next one in line? At what point does the aircraft simulator become uncontrollable or unrecoverable? Factor in the weather, turbulance, etc.
You should have some sort of idea as to what happened in what sequence and what type of break up they were looking at?
and

1)Without knowing what triggered the ACARS messages, how could you feed this into a simulator? (Assuming simulators have a total ACARS simulation which they do not).
....but can they, and have they, compared the initial ACARS messages, possibly the ones with the initial problem, with those of the other 4 or so known and mentioned very similar cases with the pitot tubes... Yes in the other incidents the pilots were able to regain control after a couple of minutes but I would think if the problems all arose from the same cause then the initial ACARS messages of those incidents during that time would be the same or very similar. They surely have a maintenace log of those. Have not seen anything on this yet...
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Old 17th Jun 2009, 21:25
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BigHitDH - with its poor resolution, that photo doesn't contribute to me what you see.

The Galley is installed as a unit (module) at the plant, so its strength is intrinsic, but well short of a/c substructure design. It may well have been robust enough to resist fragmentation while falling (free, on its own), but probably not strong enough to resist high speed air mass. If a/c underwent some sort of structural compromise of the pressure hull, doesn't mean it didn't remain substantially complete to enter the water at a velocity much lower than that experienced at cruise.
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Old 17th Jun 2009, 21:28
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Originally Posted by BigHitDH
lomapaseo, PJ2,

I find your "shrapnel" comments interesting, I had the same thought when I first studied photos of the VS.

Take a look at this shot: http://www.fab.mil.br/portal/voo447/...609/foto_3.jpg

I can see 3 "cuts" in the leading edge of the VS, anyone else concur?
Concur.

But how, why and when of course are different questions.
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Old 17th Jun 2009, 21:32
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Quote:
Originally Posted by overthewing
This is doubtless a dumb set of questions; if so, I apologise.

If you're flying the plane, and all the computers suddenly throw in the towel, is there any way of knowing what altitude you're at?

If you suspect that the problem is iced-up pitots, would descending to a lower altitude in order to unblock the tubes be sensible, or not?

Is there any way to know that you're a lot closer to the ocean than you'd like to be?



I sense that you are suggesting they possibly descended to find warm air to melt the frozen pitot tubes and then possibly impacted the ocean because they didn't know their altitude.



1) Descending to warm air would mean a huge fuel penalty. They only have enough fuel to reach their destination at cruising altitudes. Descending even for a short time would mean they would not have enough fuel to complete the flight.

2) The standby altimeter relies on barometric pressure only and will continue to give accurate readings even with total electric or computer failure.
Lost,
I'm very sorry but I have to disagree:
ETOPS flight planing has legal requirements for fuel reserves in case of In-flight Engine Shut Down, plus, de-pressurization (one or two engines running) to reach ETOPS suitable alternate aerodromes. In warm air (equatorial area) one reaches positive TAT readouts between 20 to 15000, and I'm sure a very positive TAT at about 10000'. In the event a pilot decides to descent for safety reasons, there is no pressure to continue to destination. Commercial interests, always come after safety. He may latter decide to climb again, but the decision process to resolve a failure is far more important than to comply with time-tables.
Flyinheavy:
As far as I have seen the ISIS has the Altimeter included, so not so sure about Stby Altm.
I tend to agree with you. And in my very humble opinion, without IR's and a faulty ISIS, they would not have the slightest chance to keep control of the aircraft.
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Old 17th Jun 2009, 21:40
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Aft CG?

Haven't seen it mentioned. What would be the expected CG at cruise?

Some of the data are consistent with a flat spin.

GB
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Old 17th Jun 2009, 21:41
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From the Air India 182 investigation report:

The [floating]wreckage consisted mainly of various leading edge skin panels of the left and right wings, left wing tip, spoilers, leading edge and trailing edge flaps, engine cowlings, flap track canoe fairing pieces, landing gear wheel well doors, pieces of elevator and aileron, cabin floor panels, cabin overhead and upper deck bins, passenger seats, life vests, slide rafts, hand baggage, suitcases, personal effects and a number of internal fittings. The floating wreckage constitutes about three to five percent of the aircraft structure.
................

The wreckage was then transported from Ireland to Bombay, India where it underwent further examination by the Floating Wreckage Structures Group which then produced a report which was submitted to the Indian Inquiry. The report concluded:
- There was no evidence of fire damage.
- There was no evidence of lightning strike damage.
- The cabin floor panels from the forward and rear sections of the aircraft separated from the support structure in an upward direction (floor to ceiling) pulling free from the attaching screws and, in some cases, breaking the vertical web of the seat track/floor beams.
- The position of the leading edge flap rotary actuator and the damage to the flap structure indicated that the leading edge flaps were in the retracted position.
- The six spoiler actuators found were in the retracted position. The lower surface of all the spoiler panels showed signs of spanwise skin splits with the edges curled into the core of the honeycomb. The report concluded that this was possibly due to the loading of the spoilers by being deployed in flight at high speed, resulting in compression on the lower surfaces. This, in turn, caused splitting of the lower skin into the honeycomb.
- The right wing root leading edge, number 3 engine inboard fan cowling, the right inboard midflap inboard leading edge, and the right stabilizer root leading edge all exhibited damage possibly due to objects striking the right wing and stabilizer before water impact.

In addition to the above conclusions, the following significant information regarding the floating wreckage is noted in the report:
- The aircraft was carrying a -7Q engine at the 5th pod and a -7J 5th pod kit in the aft cargo compartment. In all there were 14 engine fan cowls (four in the aft cargo compartment). Out of these 14 fan cowls, nine, including six from the working engines and three from the aft cargo compartment, and two additional pieces of fan cowls were found. Five of the fan cowls from the working engines showed folding damage lines at about the three and nine o'clock positions. The number 3 engine inboard fan cowl had severe impact damage on its leading edge and had small outward puncture holes but no penetration through the outer skin in the lower centre region. The two fan cowls of the -7J 5th pod kit stowed in the aft cargo compartment showed severe damage. One piece was cut at one corner in an arc of about 20 inches diameter and its external skin was peeled back.

- The cockpit entry door and the side bulkhead panel were found relatively intact but had come out of their attachments.
- Twelve toilet doors out of 16 were found and were relatively intact but had come out of their attachments.
- Cabin interior panels and overhead bins of the main and upper decks which were recovered exhibited only minor damage.
- The wooden boxes which contained the fan blades of the 5th pod engine were loaded in container 24L in the forward cargo compartment and were found broken apart exhibiting no burn marks.
- One passenger oxygen bottle and one portable oxygen bottle were recovered and showed no sign of damage.
.....

- Two pieces of the cover of an overhead locker originating above either door 2R or 4R were also found on the foreshore [of Wales]. They were partially damaged and blackened by fire. Mr. Clancy [an explosives expert] concluded that this indicated the presence of fire.

The CASB in its examination of the floating wreckage noted the following:
- The fan cowls of the number 4 engine had a series of five marks in a vertical line across the centre of the Air India logo on the inboard facing side of the fan cowl. These marks had the characteristic airfoil shape of a turbine blade tip. It is possible that a portion of the turbine parted from the number 3 engine and struck the cowl of the number 4 engine.
- The upper deck storage cabinet which was located on the left side had unusual damage to its bottom. A large rounded dent in the bottom inboard edge of this stiff cabinet structure revealed smooth stretching without breakthrough. The damage did not seem to be achievable by inertia or impact forces as the cabinet except for the bottom was undamaged. The damage was considered by a CASB investigator to be compatible with the spherical front of an explosive shock wave generated below the cabin floor and inboard from the cabinet; however, it is not known if this damage could be caused by some other means.
- The right wing root fillet which faired the leading edge of the wing to the fuselage ahead of the front spar had a vertical dent similar to that which would have resulted had the fillet run into a soft cylindrical object with significant relative velocity. The paint on the inboard chord appeared to be scorched brown in the centre areas of three honeycomb panels. It has been determined that sudden heat can turn these panels brown, but it is not known if other reasons for the discolouration exist. The fillet abutted the fuselage side at the aft end of the forward cargo compartment.
Would seem a greater variety of wreckage recovered from AI182 than from AF447, and more helpful to the investigators with respect to the sequence.

Last edited by SaturnV; 17th Jun 2009 at 21:53.
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Old 17th Jun 2009, 21:54
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Air India 182 autopsy results.

2.9 Medical Evidence
Medical examination was conducted on the 131 bodies recovered after the accident. This comprises about 40 per cent of the 329 persons on board. It should be noted that assigned seating is based on preliminary information. Also, the exact position of passengers is not certain because it is not known if passengers changed their seats after lift-off. On the information available, the passengers were seated as follows:

Passengers
Seats Available Occupied Bodies Identified

Zone A 16 1 0
Zone B 22 0 0
Upper Deck 18 7 0
Zone C 112 104 + 2 29
Zone D 86 84 + 1 38
Zone E 123 105 + 3 50
SUB-TOTAL 377 301 (+6 infants) 117
Crew:
Flight Deck 3 3 0
Cabin 19 19 5
TOTAL 399 329 122

There were 30 children recovered and they showed less overall injury. The average severity of injury increases from Zone C to E and is significantly less in C than in Zones D and E.

Flail pattern injuries were exhibited by eight bodies. Five of these were in Zone E, one in Zone D, two in Zone C and one crew member. The ignificance of flail injuries is that it indicates that the victims came out of the aircraft at altitude before it hit the water. There were 26 bodies that showed signs of hypoxia (lack of oxygen), including 12 children, 9 in Zones C, 6 in Zone D and 11 in Zone E. There were 25 bodies showing signs of decompression, including 7 children. They were evenly distributed throughout the zones, but with a tendency to be seated at the sides, particularly the right side (12 bodies).

Twenty-three bodies showed evidence of receiving injuries from a vertical force. They tended to be older, seated to the rear of the aircraft (4 in Zone C, 5 in Zone D, 11 in Zone E, 2 crew and 1 unknown), and 16 had little or no clothing. Twenty-one bodies were found with no clothing, including three children. They tended to be seated to the rear and to the right (3 in Zone C, 5 in Zone D, 11 in Zone E and 2 unknown).

There were 49 cases showing signs of impact-type injuries, including 19 children (15 in Zone C, 15 in Zone D, 15 in Zone E, 1 crew member and 3 unknown).

There is a general absence of signs indicating the wearing of lap belts. Pathological examination failed to reveal any injuries indicative of a fire or explosion.
*See Appendix C for interior seating arrangement.
From a report of flail injuries from use of ejection seats:
Q forces are related to indicated airspeed rather than true airspeed. These forces increase with the square of the velocity thus producing the recommendation that pilots should reduce airspeed and increase altitude prior to ejection (3). Q forces have been divided into those produced by windblast, resulting in injuries such as petechial and subconjunctival hemorrhage, and those injuries produced by flailing of the head and extremities. Flail injuries are the result of the differential deceleration of the extremities in relationship to the torso and seat. Flail injury occurs as a consequence of the extremities leaving their initial position, building up substantial acceleration, and then suddenly stopping. The sudden stop may produce a bone fracture, joint dislocation, or total disarticulation.
The Brazilian autopsy reports are suggestive of numerous bodies with flail injuries.
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Old 17th Jun 2009, 22:21
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Lost in Saigon

Should'nt you consider TAT rather than OAT??? What do you think the TAT was??
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Old 17th Jun 2009, 22:36
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DC ATE and CAPT AIRCLUES

You two are the only people on this thread worth reading.

and given a choice between descending and getting my pitot tubes back and using more fuel or NOT getting my pitot tubes back and dying...what is wrong with this question.

I haven't left North America in my flying. But I have had to fly below the Flight Levels in jet transports for various reasons...the fuel penalty isn't that great...it is doable,manageable etc.

GEE GUYS (not dc8 and clues) ...what happens if you lose pressurization...and have to fly at 10,000feet!


shaking my head at some of the stuff I see.
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Old 17th Jun 2009, 22:51
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I can see 3 "cuts" in the leading edge of the VS, anyone else concur?

I finally downloaded and collected all the pics that managed to survive the posts here (probably only 20%). This makes it a little easier to reference comments back to a pic.

My quick look at the VS leading edge does shows the cuts that you refer but I could' only resolve those if I had a pic 0.5-1.0 X. Somebody with a before pic (airliners net?) might confirm if they they're before hand. Otherwise I would suspect rope lashings to recover the part.

I now see what PJ2 was referring in his posts. Most of what I see are breakups and scarring at relatively low speed not a dive into the water.

I tend to go along with the reports from the somebody close to the investigation that the aircraft broke up partially before it hit the ground (like AI, SA, PA103, TWA800 etc.). However many of the photos are probably from parts that stayed with the larger aircraft sections until they struck the water at freefall speed (significant drag so their terminal velocity would have been low).

Thus I suspect that allowing for some drift the rest of the plane is in the begining of the drift area where parts like the galley and crew rest seats were found.

For any of you water borne experts out there. Is it practical to plant a couple hundred floating bottles (or rubber ducks) out there and track where they end up in several days just to confirm how far the currents might have moved them until they were recovered? Forget the underwater currents, the stuff that I have seen never got more than a few feet below the surface (no signs of hydraulic loading)

of course the investigators are way ahead of us internet folks on this stuff.
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Old 17th Jun 2009, 22:56
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I believe I have most pics in the URL below - if anyone knows of (relevant) missed ones please PM me the URL:

AF447 Photos
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Old 17th Jun 2009, 23:03
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DorianB

I believe I have most pics in the URL below - if anyone knows of (relevant) missed ones please PM me the URL:
Yes indeed you have the best collection I have seen

You are a great help to folks like me that devour photos for confirmation of speculations.

I wonder where Machaca is he usually has great sources for this kind of stuff
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Old 17th Jun 2009, 23:29
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Another VS pic released by the French army

This link redirects you to the picture, not to the report (sorry, I did try to insert the pic itself but I couldn't):

The Associated Press: Autopsies suggest Air France jet broke up in sky



This photo released Wednesday June 17, 2009 by the French army shows soldiers approaching a piece of debris believed to be part of Air France flight 447, during continuing searches for debris and bodies on Friday June 12, 2009 in the Atlantic Ocean. Air France Flight 447, en route to Paris from Rio de Janeiro with 228 passengers and crew, went down in the ocean on June 1. (AP Photo/ECPAD) NO SALES
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Old 17th Jun 2009, 23:32
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protectthehornet:
and given a choice between descending and getting my pitot tubes back and using more fuel or NOT getting my pitot tubes back and dying...what is wrong with this question.

I haven't left North America in my flying. But I have had to fly below the Flight Levels in jet transports for various reasons...the fuel penalty isn't that great...it is doable,manageable etc.

GEE GUYS (not dc8 and clues) ...what happens if you lose pressurization...and have to fly at 10,000feet!


shaking my head at some of the stuff I see.
Extended Twin [Engined] OPS require a certain amount of extra fuel to cope for Inflight Engine Shut-Down and Depressurization. This means that, if one has to descent to 10.000ft in any phase or part of the flight, one is assured to have enough fuel to reach a suitable alternate airport.

Having that in mind, if a pilot gets (yes it shows on ECAM) a failure of pitot heat, (and is unable to reset or cope with the situation) one can elect to descend to a lower altitude. TAT is the reference temperature to have in mind in such case and a descent to about 15 to 10000' will be enough to get rid off the icing conditions.

Again, in my opinion, they didn't have enough conditions to do it, due to lost of visual and attitude indications. (it doesn't mean they haven't tried it...)

I honestly think that we are loosing the big picture here. What we need to find out is why did that crew elected (or not) to fly into the bad weather and what happened to produce such a great deal of failures, with especial emphasis to [all] IR's and (partially, at least) to the ISIS. The rest is only a consequence, not the reason.

An A330 (or any other aircraft) is not flyable (at night, in weather) without attitude indication. The A330, in particular, may be flown without Flight Control Computers (PRIM's and SEC's), with an Hydraulic Double Failure, in Emergency Electrical Configuration, even without both engines (for a certain period of time, of course), but the failure of ALL IR's and ISIS is unquestionably problematic.(I know this is pure speculation, but - lets face it - that's what we are all doing here).

Just my two cents...ready to be flamed.

Edit to say, in my defense: if those IR's were not failed, why didn't we had a positive and unquestionable statement of Airbus Industrie mentioning a "partial failure"?

Last edited by aguadalte; 17th Jun 2009 at 23:43.
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Old 17th Jun 2009, 23:48
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Lompaseo - botttles and rubber ducks

Quote
Is it practical to plant a couple hundred floating bottles (or rubber ducks) out there and track where they end up in several days just to confirm how far the currents might have moved them until they were recovered? Forget the underwater currents, the stuff that I have seen never got more than a few feet below the surface (no signs of hydraulic loading)
Unquote

It would probably have been a good a idea to drop transmitter-equipped markers where wreckage or bodies were found, early on in the search. The aircraft that found the wreckage may well have done so, though I haven't seen any reference thereto. Bodies would have similar buoyancy and would tend to drift reasonably closely; objects like the galley, with much more windage, would be more subject to localised winds.

Obviously, the longer any collection of flotsam floats, the more it's likely to disperse, particularly so where the aircraft went down.
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Old 17th Jun 2009, 23:57
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I'm sure that the oceans are being monitored (and not by plastic water bottes) to collect data -- there is a lot of monitoring stations that give real-time data on ocean currents -- probably not in this area, and there are a lot of computer models. I am sure that data is being collected by the ships as they trawl for debris to get real-time data -- depth and surface information. again, something I know a fair bit about. my posts keep being deleted.
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Old 18th Jun 2009, 00:03
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Broadreach, Lompaseo,

Funny you should use ducks as an example, it reminded me of the "Friendly Floatees" accident that actually turned into a very valuable piece of science, makes for an interesting read:

Friendly Floatees - Wikipedia, the free encyclopedia
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